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AGENDA
STORMWATER UTILITY COMMISSION
REGULAR SESSION
MARCH 18, 2021
ONLINE ZOOM MEETING
JOIN ZOOM MEETING
https://orovalley.zoom.us/j/93703947281?pwd=MGVCbWY4MXRkVWNadHIveDU5NWVrUT09
To attend via phone ONLY, dial 1-346-248-7799
enter Meeting ID: 937 0394 7281, then enter Passcode: 732969
REGULAR SESSION AT OR AFTER 4:00 PM
CALL TO ORDER
ROLL CALL
CALL TO AUDIENCE - at this time, any member of the public is allowed to address the Commission on any
issue not listed on today’s agenda. Pursuant to the Arizona open meeting law, individual Commission
members may ask Town staff to review the matter, ask that the matter be placed on a future agenda, or
respond to criticism made by speakers. However, the Commission may not discuss or take legal action on
matters raised during "Call to Audience". In advance requests to speak are preferred and may be sent to
the Commission Secretary at stwov@orovalleyaz.gov no later than one hour before the meeting begins.
COUNCIL LIAISON COMMENTS (INFORMATIONAL ONLY)
DIRECTORS REPORT (INFORMATIONAL ONLY)
REGULAR SESSION AGENDA
1.REVIEW AND APPROVAL OF THE JANUARY 21, 2021 MEETING MINUTES
2.RECOGNITION OF OUTGOING STORMWATER UTILITY COMMISSIONER JACK STINNETT
3.DISCUSSION OF STORMWATER MEETINGS AND EVENTS
4.DISCUSSION OF UPCOMING STAFF REQUEST TO THE TOWN COUNCIL TO ADOPT CHANGES TO
TOWN CODE CHAPTER 17 - FLOODPLAIN MANAGEMENT
5.REPORT AND DISCUSSION OF THE STORMWATER UTILITY'S CARTEGRAPH / GIS INTEGRATION
AND ASSET MANAGEMENT PROCEDURES
6.DISCUSSION OF 2021 STORMWATER UTILITY COMMISSION FIELD TRIP DELIVERY
ALTERNATIVES
7.DISCUSSION AND POSSIBLE ACTION REGARDING THE CANCELLATION OF THE APRIL 15,
2021 SWUC REGULAR SESSION MEETING
FUTURE AGENDA ITEMS
ADJOURNMENT
POSTED: 3/11/21 at 5:00 P.M.
When possible, a packet of agenda materials as listed above is available for public inspection at least 24 hours
prior to the Commission meeting in the Town Clerk's Office between the hours of 8:00 a.m. – 5:00 p.m.
The Town of Oro Valley complies with the Americans with Disabilities Act (ADA). If any person with a disability
needs any type of accommodation, please notify the Town Clerk’s Office at least five days prior to the Commission
meeting at 229-4700.
INSTRUCTIONS TO SPEAKERS
Members of the public have the right to speak during any posted Public Hearing. However, those items
not listed as a Public Hearing are for consideration and action by the Stormwater Utility Commission
during the course of their business meeting. Members of the public may be allowed to speak on these
topics at the discretion of the Chair.
In accordance with Amendment #2 of the Mayoral Proclamation of Emergency issued on March 27, 2020, the
following restrictions have been placed on all public meetings until further notice:
1. In-person attendance by members of the public is prohibited.
2. Members of the public can either watch the public meeting online
https://www.orovalleyaz.gov/town/departments/town-clerk/meetings-and-agendas or, if they would like to
participate in the meeting (e.g. speak at Call to Audience or speak on a Regular Agenda item), they can attend the
meeting and participate via the on-line meeting application, Zoom,
https://orovalley.zoom.us/j/93703947281?pwd=MGVCbWY4MXRkVWNadHIveDU5NWVrUT09, or may participate
telephonically only by dialing 1-346-248-7799 then enter Meeting ID: 937 0394 7281, then enter Passcode: 732969
prior to or during the posted meeting.
3. If a member of the public would like to speak at either Call to Audience or on a Regular Agenda item, please
"raise your hand" during the meeting when the Chair announces that it is the appropriate time to do so. For those
participating in the meeting through Zoom, place your cursor towards the bottom, middle of the page and look for
the "raise your hand" icon and click on it to "raise your hand" to speak. For those participating via phone only,
press *9 to "raise your hand".
4. All members of the public who participate in the Zoom meeting either with video or telephonically will enter the
meeting with microphones muted. For those participating via computer/tablet/phone device, you may choose
whether to turn your video on or not. Those participating via computer/tablet/phone device can click the “raise your
hand” button during the Call to the Public or Regular Agenda item, and the Chair will call on you in order. For
those participating by phone, you can press *9, which will show the Chair that your hand is raised. When you are
recognized at the meeting by the Chair, your microphone will be unmuted by a member of staff and you will have
three minutes to speak before your microphone is again muted.
5. If a member of the public would like to submit written comments to the Stormwater Utility Commission for their
consideration prior to the meeting, please email those comments to stwov@orovalleyaz.gov no later than sixty
minutes before the public meeting. Those comments will then be electronically distributed to the public body prior
to the meeting. If you have questions, please contact the Stormwater Utility Commission's Recording Secretary, at
520-229-4850 or email at stwov@orovalleyaz.gov
Thank you for your cooperation.
“Notice of Possible Quorum of the Oro Valley Town Council, Boards, Commissions and Committees: In
accordance with Chapter 3, Title 38, Arizona Revised Statutes and Section 2-4-4 of the Oro Valley Town Code, a
majority of the Town Council, Board of Adjustment, Historic Preservation Commission, Parks and Recreation
Advisory Board, Stormwater Utility Commission, and Water Utility Commission may attend the above referenced
meeting as a member of the audience only."
Stormwater Utility Commission 1.
Meeting Date:03/18/2021
Submitted By:Yarina Hynd, Public Works
SUBJECT:
REVIEW AND APPROVAL OF THE JANUARY 21, 2021 MEETING MINUTES
RECOMMENDATION:
Staff recommends approval.
EXECUTIVE SUMMARY:
N/A
BACKGROUND OR DETAILED INFORMATION:
N/A
FISCAL IMPACT:
N/A
SUGGESTED MOTION:
I MOVE to approve (approve with changes), the January 21, 2021 meeting minutes.
Attachments
01-21-2021 Draft Minutes
D R A F T
MINUTES
STORMWATER UTILITY COMMISSION
REGULAR SESSION
JANUARY 21, 2021
MEETING HELD VIA ZOOM
REGULAR SESSION AT OR AFTER 4:00 PM
CALL TO ORDER
Chair Cuffari called the meeting to order at 4:00 P.M.
ROLL CALL
Present: Joan Brown, Vice Chair
Gary Mattson, Commissioner
Dave Parker, Commissioner
Jack Stinnett, Commissioner
Joe Cuffari, Chair
Staff Present:Aimee Ramsey, Assistant Director Public Works
John Spiker, Stormwater Division Manager
Scott Bennett, Stormwater GIS Analyst
Harry Greene, Town Council Liaison
CALL TO AUDIENCE
There were no speaker requests or raised hands during the Call to Audience.
COUNCIL LIAISON COMMENTS (INFORMATIONAL ONLY)
Incoming Council Liaison Harry Greene commented that he had an excellent meeting with two of the Stormwater
Utility (SWU) staff to bring him up to speed, and he is looking forward to joining the Commission.
DIRECTORS REPORT (INFORMATIONAL ONLY)
Division Manager John Spiker reported on the following subjects:
Renovations are going on in the SWU building.
The year 2020 was the driest year on record. The rain gauge hosted by Pima County at the SWU building
registered 4 1/4 inches of rain for 2020. On average, we usually receive between 10 – 12 inches of rainfall.
SWU sent in a FEMA Brick Grant proposal, which is for building resilient infrastructure in communities.
This was put in for the Highland Wash Mitigation Project.
REGULAR SESSION AGENDA
01/21/2021 Minutes, Stormwater Utility Commission Regular Session 1
1.REVIEW AND APPROVAL OF THE NOVEMBER 19, 2020 MEETING MINUTES
Motion by Commissioner Jack Stinnett, seconded by Vice Chair Joan Brown to approve the November
19, 2020 meeting minutes.
Vote: 5 - 0 Carried
2.WELCOME AND INTRODUCTION FOR NEW STORMWATER UTILITY COMMISSION MEMBERS
Mr. Spiker reported that the Stormwater Utility Commission (SWUC) has two new Commissioners this
year, Gary Mattson and Dave Parker, and a new Council Liaison Harry Greene. Mr. Spiker added that
the SWUC is an advisory board to the Town Council on matters pertaining to stormwater and floodplain
management.
3.DISCUSSION OF MEETINGS AND EVENTS
Mr. Spiker reported on recent meetings and events.
4.DISCUSSION OF 2020/2021 TOWN OF ORO VALLEY MS4 COMPLIANCE SCHEDULE, SECOND
QUARTER REPORT
GIS Analyst Scott Bennett reported on the second quarter of the Town of Oro Valley (TOV) MS4
Compliance Schedule. This report addresses what we've done through the second quarter.
Discussion ensued among Commissioners and staff as to the availability of a map that shows all
outfalls, where the water is leaving public area and heading into washes. Mr. Spiker commented that
much of that information is mapped on an internal GIS database and asset management system, but
that maps could be made available to the Commissioners.
Assistant Director/Public Works Aimee Ramsey suggested that at our next meeting we could have staff
present on our dataset and our Cartegraph program, and how we use it to manage our systems.
Commissioner Brown asked the timeframe for BMP 6.1 Annual Inspection of Town of Oro Valley
Municipal Operations and Maintenance Facilities (done once per Fiscal Year). Mr. Bennett stated
this inspection is done in May (usually the fourth quarter of each year).
5.PRESENTATION AND POSSIBLE DISCUSSION OF SLOPE EROSION MITIGATION PROJECT
COMPLETED BY CATALINA SHADOWS HOA
Mr. Spiker gave a presentation on Catalina Shadows HOA mitigation project regarding slope erosion in
their neighborhood. In 2018 the HOA approached the Town and Pima County Flood Control District
(PCFCD) regarding slope erosion, it was deemed to be a private property, but TOV and the County
remained engaged to help provide guidance and to ensure no adverse impacts to Big Wash Preserve
or Pima County Waste Water (PCWW) sewage lines. Upon completion the HOA had spent
approximately $150,000.00 towards stabilizing the slope. Mr. Spiker wanted to recognize this endeavor
as a success, not only for the HOA, but as part of the outreach of SWU.
Discussion ensued among the Commission regarding the success of the hydro seeding efforts, Mr.
Spiker commented that the HOA was proactive in supplying irrigation to ensure the success of the
hydroseed.
Prior to the meeting, audience members, Ms.Devon Sloane, President of Catalina Shadows HOA, and
Dick Honn, resident, asked to speak on this Agenda Item. Ms. Sloane thanked the SWU for the
01/21/2021 Minutes, Stormwater Utility Commission Regular Session 2
Dick Honn, resident, asked to speak on this Agenda Item. Ms. Sloane thanked the SWU for the
recognition of this project and also thanked Dick Honn, resident, for taking on this project over several
years. Mr. Honn thanked members of the SWU for their continuing help:
Mike Todnem, previous Stormwater Division Manager
John Lynch, Stormwater Project Manager
John Spiker, Stormwater Division Manager
Mr. Honn also thanked Clint Elder of Borderland Construction for the free dirt used on the project. Mr.
Honn made a final recognition of drainage manager for Catalina Shadows, Doug McKee, TOV resident,
who passed away in 2016. Mr. Honn stated that he regretted that Mr. McKee was not here today to
personally thank the SWU.
6.NOMINATION AND ELECTION OF STORMWATER UTILITY COMMISSION CHAIR
Motion by Vice Chair Joan Brown, seconded by Commissioner Gary Mattson to nominate Joe Cuffari
as Stormwater Utility Commission Chairman.
Vote: 4 - 0 Carried
Other: Chair Joe Cuffari (ABSTAIN)
7.NOMINATION AND ELECTION OF STORMWATER UTILITY COMMISSION VICE CHAIR
Commissioner Stinnett nominated Commissioner Brown.
Commissioner Brown declined.
Commissioner Brown nominated Commissioner Stinnett.
Commissioner Stinnett declined.
Commissioner Brown nominated Commissioner Parker.
Commissioner Parker accepted.
Motion by Vice Chair Joan Brown, seconded by Commissioner Jack Stinnett to nominate
Commissioner Parker as Vice Chairman of the Stormwater Utility.
Vote: 4 - 0 Carried
Other: Commissioner Dave Parker (ABSTAIN)
8.DISCUSSION AND POSSIBLE ACTION REGARDING THE CANCELLATION OF THE FEBRUARY 18,
2021 STORMWATER UTILITY COMMISSION REGULAR SESSION MEETING
Discussion ensued among the Commission and staff.
Motion by Chair Joe Cuffari, seconded by Vice Chair Joan Brown to approve cancellation of the
February 18, 2021 Stormwater Utility Commission Regular Session Meeting.
Vote: 5 - 0 Carried
FUTURE AGENDA ITEMS
01/21/2021 Minutes, Stormwater Utility Commission Regular Session 3
FUTURE AGENDA ITEMS
Presentation on Outfalls
Highland Wash
Update on Big Horn Fire burn scar
Stormwater Field Trip
ADJOURNMENT
Motion by Commissioner Dave Parker, seconded by Commissioner Jack Stinnett to adjourn the
meeting.
Vote: 5 - 0 Carried
Chair Cuffari adjourned the meeting at 5:00 P.M.
I hereby certify that the foregoing minutes are a true and correct copy of the minutes of the regular session of the
Town of Oro Valley Stormwater Utility Commission of Oro Valley, Arizona held on the 21st day of January, 2021. I
further certify that the meeting was duly called and held and that a quorum was present.
Dated this _____ day of ____________________, 2021.
___________________________
Yarina Hynd
Office Specialist
01/21/2021 Minutes, Stormwater Utility Commission Regular Session 4
Stormwater Utility Commission 2.
Meeting Date:03/18/2021
Requested by: John Spiker, Public Works Submitted By:John Spiker, Public Works
SUBJECT:
RECOGNITION OF OUTGOING STORMWATER UTILITY COMMISSIONER JACK STINNETT
RECOMMENDATION:
N/A
EXECUTIVE SUMMARY:
Commissioner Stinnett has moved on from the Stormwater Utility Commission after 2 years of service. Upon
graduation from the US Naval Academy, Jack made his way into engineering and management in the Nuclear
Power industry, then onto the automotive and engine component industry, finally ending his career as President
and CEO of Morris Material Handling in Milwaukee, WI. Jack and his wife Connie moved to Oro Valley in 2011
where Jack was eager to serve the community. He signed up with the Oro Valley Parks and Recreation Advisory
Board (PRAB) in 2012, serving as Chair in 2013 and into 2014. After his stint with PRAB, Jack again felt the pull of
community service and signed up to volunteer with the Stormwater Utility Commission in 2019.
We extend a hearty thank you and well wishes to Jack for his contributions to not only the Stormwater Utility, but to
the Town of Oro Valley.
BACKGROUND OR DETAILED INFORMATION:
N/A
FISCAL IMPACT:
N/A
SUGGESTED MOTION:
N/A
Stormwater Utility Commission 3.
Meeting Date:03/18/2021
Requested by: John Spiker, Public Works Submitted By:John Spiker, Public Works
SUBJECT:
DISCUSSION OF STORMWATER MEETINGS AND EVENTS
RECOMMENDATION:
N/A
EXECUTIVE SUMMARY:
The following is a list of immediate past, and future, stormwater meetings and events.
February 17, 2021 - Pima County Flood Control District Advisory Committee Meeting
March 17, 2021 - Pima County Flood Control District Advisory Committee Meeting
March 18, 2021 - Stormwater Utility Commission Regular Session Meeting
March 25 - 26, 2021 - Santa Cruz River Research Days
April 15, 2021 - Stormwater Utility Commission Regular Session Meeting (possible cancellation)
April 21, 2021 - Pima County Flood Control District Advisory Committee Meeting
BACKGROUND OR DETAILED INFORMATION:
For informational purposes only.
FISCAL IMPACT:
N/A
SUGGESTED MOTION:
N/A
Stormwater Utility Commission 4.
Meeting Date:03/18/2021
Requested by: John Spiker, Public Works Submitted By:John Spiker, Public Works
SUBJECT:
DISCUSSION OF UPCOMING STAFF REQUEST TO THE TOWN COUNCIL TO ADOPT CHANGES TO TOWN
CODE CHAPTER 17 - FLOODPLAIN MANAGEMENT
RECOMMENDATION:
For informational purposes only.
EXECUTIVE SUMMARY:
See below.
BACKGROUND OR DETAILED INFORMATION:
With approval by the Town Engineer, and others, the attached copy of the revised Town Code Chapter 17 will go
before the Mayor and Council as a Resolution and Public Hearing sometime in the near future. Beforehand,
Chapter 17 will also be reviewed by Town staff as well as Brian Cosson and others from the Arizona Department of
Water Resources (ADWR), and presented here at the Stormwater Utility Commission. The current Floodplain and
Erosion Hazard Management Ordinance No. (O) 17-04 was passed and adopted by the Town Council on April 5,
2017. More recently, the ADWR conducted a Community Assistance Contact (CAC) on July 17, 2020, which
resulted in recommendations, among others, that the Town update Chapter 17 to incorporate standard wording
contained State of Arizona Floodplain Management Model Ordinance, dated June 2020. The attached annotated
copy of Chapter 17 has been updated accordingly. Changes were limited to those needed to bring Chapter 17 into
conformance with the state Model Ordinance, as well as to be consistent with changes being made to the Town of
Oro Valley Drainage Criteria Manual. Higher standards added to the Ordinance in 2017, related to participation in
the FEMA Community Rating System (CRS), were deleted because of the Town’s earlier choice not to participated
in the CRS. The most notable changes are as follows.
Article 17-2-1 Definitions. Archaic terms were deleted, and others were added or modified to conform to the
Model Ordinance. Duplicative or conflicting language was also deleted.
1.
Article 17-2-1 Definitions. The term Base Flood has been changed to mean a 100-year peak discharge of
100 cubic feet per second (100 cfs) instead of 50 cfs. This was done to be consistent with other local
jurisdictions.
2.
Article 17-4-3 Duties of the Floodplain Administrator and Use Permit Procedures. Clarification was added
regarding issuance of building permits within effective FEMA Special Flood Hazard Areas.
3.
FISCAL IMPACT:
N/A
SUGGESTED MOTION:
This is for informational purposes only.
Attachments
Chapter 17 Revisions
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 1 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
CHAPTER 17
FLOODPLAIN AND EROSION HAZARD MANAGEMENT
Articles:
17-1 Statutory Authorization, Findings of Fact, Purpose and Methods
17-2 Definitions
17-3 General Provisions
17-4 Administration
17-5 Provisions for Flood Hazard Reduction
17-6 Appeal and Variance Procedures
17-7 Ordinance Amendments
17-8 Fees
Article 17-1
STATUTORY AUTHORIZATION, FINDINGS OF FACT, PURPOSE AND
METHODS
Sections:
17-1-1 Statutory Authorization
17-1-2 Findings of Fact
17-1-3 Statement of Purpose
17-1-4 Methods of Reducing Flood Losses
17-1-1 Statutory Authorization.
The Legislature of the State of Arizona has, in ARS § 48-3610, enabled the Town of Oro Valley to assume the
powers and duties for floodplain management and adopt regulations in conformance with ARS § 48-3609 that
are designed to promote the public health, safety, and general welfare of its citizenry. Therefore, the Town
Council of Oro Valley, Arizona, does ordain as follows. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 2 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
17-1-2 Findings of Fact.
A. The flood hazard areas Special Flood Hazard Areas of Oro Valley are subject to periodic inundation that
may result in loss of life and property, health and safety hazards, disruption of commerce and governmental
services, extraordinary public expenditures for flood protection and relief, and impairment of the tax base, all
of which adversely affect the public health, safety and general welfare.
B. These flood losses are caused by the cumulative effect of obstructions in the regulatory floodplain Special
Flood Hazard Areas, which increase flood heights and velocities. Also, when these obstructions are
inadequately anchored, they may cause damage in other areas. Uses that are inadequately flood-proofed,
elevated, or otherwise protected from flood damage also contribute to the flood loss. ((O)17-04, 04/05/2017;
(O)05-35, 10/05/2005)
17-1-3 Statement of Purpose.
It is the purpose of this chapter to promote the public health, safety, and general welfare, and to minimize
public and private losses due to flood conditions in specific areas by provisions designed:
A. To protect human life and health;
B. To minimize expenditure of public money for costly flood control projects;
C. To minimize the need for rescue and relief efforts associated with flooding and generally undertaken at the
expense of the general public;
D. To minimize prolonged business interruptions;
E. To minimize damage to public facilities and utilities such as water and gas mains, electric, telephone, and
sewer lines, and streets and bridges located in the regulatory floodplain Special Flood Hazard Areas;
F. To help maintain a stable tax base by providing for the protection of regulatory floodplain sound use and
development of the Special Flood Hazard Areas and erosion hazard areas;
G. To ensure that potential buyers are notified that property is in a regulatory floodplain;
H. To ensure that those who occupy an area in a regulatory floodplain assume responsibility for their actions;
and
I. To participate in and maintain eligibility for flood insurance and disaster relief. ((O)17-04, 04/05/2017;
(O)05-35, 10/05/2005)
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 3 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
17-1-4 Methods of Reducing Flood Losses.
In order to accomplish its purposes, this chapter includes methods and provisions for:
A. Restricting or prohibiting uses which are dangerous to the public health, safety, and welfare as well as
public and private property, due to water or development hazards; or which result in increased damages to
development or increases in flood heights or velocities;
B. Requiring that uses vulnerable to floods, including facilities which serve such uses, be protected against
flood damage at the time of start of construction;
C. Controlling the alteration of natural floodplains, stream channels, and natural protective barriers, which
help to accommodate natural flood storage potential or the channelization of floodwaters;
D. Controlling filling, grading, dredging, and other development that may increase flood damage; and
E. Preventing or regulating the construction of flood barriers that unnaturally divert floodwaters, or that may
increase flood hazards in other areas. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
Article 17-2
DEFINITIONS
Sections:
17-2-1 Definitions
17-2-1 Definitions.
Unless specifically defined below, words or phrases used in this chapter shall be interpreted to give them the
meaning they have in common usage, and to give this chapter its most reasonable application.
Accessory Structure means a structure that is on the same parcel of property as a principal structure, the use
of which is incidental to the use of the principal structure. For floodplain management purposes, the term
includes only accessory structures used for parking and storage.
Alluvial Fan means a geomorphologic feature characterized by a cone or fan-shaped deposit of boulders,
gravel and fine sediments that have been eroded from mountain slopes, transported downstream by flood
flows, and then deposited on valley floors, and that is subject to flash flooding, high velocity flows, debris
flows, erosion, sediment movement, deposition, and channel migration.
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 4 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
Alluvial Fan – Inactive means an alluvial fan where floodwaters typically flow within incised channels, and
adjacent lands are stable.
Alluvial Fan Flooding means flooding occurring on the surface of an alluvial fan, or similar landform, which
originates at the apex; and is characterized by high-velocity flows; active processes of erosion, sediment
transport, deposition, and unpredictable flow paths.
Alluvial Fan High Hazard Area (AFHH) means an area of active alluvial fan flooding that is reserved to
convey and receive sediment and floodwater without altering, and thereby potentially increasing, the
distribution of flood hazards across the fan to otherwise inactive areas and areas located down slope.
Apex means a point on an alluvial fan, or similar landform, below which the flow path of the major stream that
formed the fan becomes unpredictable, and alluvial fan flooding can occur.
Appeal means a request for a review of the decision of the Floodplain Administrator or Town Engineer
concerning previous determinations or actions, pursuant to this chapter. request for a review of the Floodplain
Administrator's interpretation of any provision of this Ordinance or a request for a variance. Appeals are heard
and decided by the Floodplain Board.
Area of Shallow Flooding means a designated zone AO, AH, AR/AO or AR/AH on a community’s Flood
Insurance Rate Map (FIRM) with a one percent (1%) or greater annual chance of flooding to an average depth
of one (1) to three (3) feet where a clearly defined channel does not exist, where the path of flooding is
unpredictable, and where velocity flow may be evident. Such flooding is characterized by ponding or sheet
flow.
Base Flood means a flood having a one percent (1%) chance of being equaled or exceeded in any given year.
The base flood shall mean the peak discharge of a one hundred (100) year flood of fifty (50) one hundred
(100) cubic feet per second (cfs) or greater. Said flood shall be determined from an analysis of floods on a
particular watercourse, and other watercourses in the same general region, in accordance with the criteria
established by the Arizona Department of Water Resources and the Town of Oro Valley, which criteria are
hereby incorporated by reference and made a part of this chapter.
Base Flood Elevation (BFE) means the computed elevation to which floodwater is anticipated to rise during
the base flood.
Basement means any area of a structure with a subgrade floor, i.e., below the adjacent ground level.
Building. See “Structure.”
Community means any state or area or political subdivision thereof, or any Indian tribe, authorized tribal
organization, or authorized native organization, which has authority to adopt and enforce floodplain
management regulations for the areas within its jurisdiction.
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 5 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
Critical Facility means a facility such as a hospital, nursing home, police and fire stations, and other public
safety facilities that would be severely impacted by flooding interrupting critical services or leading to
significant sheltering needs for the sick or elderly.
Detention System means a type of flood control system which delays the downstream progress of floodwaters
in a controlled manner, generally through the combined use of a temporary storage area and a metered outlet
device, which causes a lengthening of the duration of the flow and thereby reduces downstream flood peaks.
Development means any manmade change to improved or unimproved real estate, including but not limited to
structures, mining, dredging, filling, grading, paving, excavation or drilling operations, and storage of
materials and equipment located within the regulatory floodplain.
Dwelling means a habitable structure.
Elevation Certificate means an administrative tool of the National Flood Insurance Program (NFIP) that is
used to provide elevation information necessary to ensure compliance with community floodplain management
ordinances, to determine the proper insurance premium rate, and to support a request for a Letter of Map
Amendment (LOMA) or Letter of Map Revision Based on Fill (LOMR-F).
Encroachment means the advance or infringement of uses, landscape vegetation, fill, excavation, permanent
structures, or development into a floodplain that may impede or alter the flow capacity of a floodplain. An
equal degree of encroachment is a standard applied to the evaluation of the effects of the encroachment on
increases in flood heights. It assumes that an encroachment, if permitted, may confer on all property owners on
both sides of the watercourse an equal right to encroach to the same degree within that reach. Since the factors
affecting hydraulic efficiency are usually not uniform within a reach, this standard will usually not result in
equal measured distances between regulatory floodway limit lines and the regulatory floodplain boundaries of
the watercourse.
Erosion means the process of the gradual wearing away of landmasses. This peril is not, per se, covered under
the National Flood Insurance Program.
Erosion Hazard Area means lands adjoining a watercourse that is regulated by this chapter which are deemed
by the Town Engineer to be subject to flood-related erosion losses (ref. the adopted Drainage Criteria Manual,
Town of Oro Valley).
Erosion Setback means the minimum horizontal distance between a structure or permanent feature and the
channel bank necessary to protect the structure/feature from flood related erosion damage. For method to be
used for determination of the erosion setback, see the adopted Drainage Criteria Manual, Town of Oro Valley.
Existing Manufactured Home Park or Subdivision means a manufactured home park or subdivision for
which the construction of facilities for servicing the lots on which the manufactured homes are affixed
(including, at a minimum, the installation of utilities, construction of streets, and either final site grading or the
pouring of concrete slabs) was completed before the effective date of the floodplain management regulations
adopted by the community.
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 6 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
Expansion to an Existing Manufactured Home Park or Subdivision means preparation of additional sites
by the construction of facilities for servicing the lots on which the manufactured homes are to be affixed
(including the installation of utilities, the construction of streets, and either final site grading or the pouring of
concrete pads).
Federal Emergency Management Agency (FEMA) means an agency of the Federal government responsible
for programs of disaster response and recovery, disaster preparedness, hazard mitigation, flood insurance, and
other programs of technical and financial assistance.
Federal Insurance and Mitigation Administration (FIMA) manages the National Flood Insurance Program.
Flood or Flooding means a general and temporary condition of partial or complete inundation of normally dry
land areas from: (1) the overflow of floodwaters; (2) the unusual and rapid accumulation or runoff of surface
waters from any source; and/or (3) the collapse or subsidence of land along the shore of a lake or other body of
water as a result of erosion or undermining caused by waves or currents of water exceeding anticipated cyclical
levels or suddenly caused by an unusually high water level in a natural body of water, accompanied by a
severe storm or by an unanticipated force of nature, such as flash flood or an abnormal tidal surge, or by some
similarly unusual and unforeseeable event which results in flooding as defined in this definition.
Flood Insurance Rate Map (FIRM) means the official map on which the Federal Emergency Management
Agency has delineated both the areas of special flood hazards Special Flood Hazard Areas and the risk
premium zones applicable to the community.
Flood Insurance Study (FIS) means the official report provided by Federal Emergency Management Agency
that includes flood profiles, the Flood Insurance Rate Map, and the water surface elevation of the base flood.
Flood Protection System means those physical structural works for which funds have been authorized,
appropriated, and expended; and which have been constructed specifically to modify flooding in order to
reduce the extent of the area within a community subject to designation as a regulatory floodplain as well as
the extent and depths of associated flooding. Such a system typically includes dams, reservoirs, levees or
dikes. These specialized flood-modifying works are those constructed in conformance with sound engineering
standards.
Floodplain or Flood-prone Area means any land area susceptible to being inundated by water from any
source (see “Flooding”).
Floodplain Administrator is the Town Engineer, or his/her designee, whose duty it is to oversee
administration and enforcement of the floodplain management regulations contained in this document.
Floodplain Board means the Town Council of Oro Valley, at such times as they are engaged in the
enforcement of this chapter.
Floodplain Management means the operation of an integrated natural resource management program
encompassing corrective and preventive measures for reducing flood and erosion damage. Floodplain
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management includes but is not limited to emergency preparedness planning, flood control works and
floodplain management regulations.
Floodplain Management Regulations means this chapter and other zoning ordinances, subdivision
regulations, building codes, health regulations, special purpose ordinances (such as grading and erosion
control), and other applications of legal and regulatory authority that control use of, and development in,
flood-prone areas. This term describes Federal, State, or local regulations, and any combination thereof, which
provide standards for preventing and reducing flood loss and damage.
Floodplain Use Permit means an official document that authorizes special activity within the regulatory
floodplains or erosion hazard areas of Oro Valley.
Flood-proofed means a watertight structure with walls substantially impermeable to the passage of water, and
with structural components having the capability of resisting hydrostatic and hydrodynamic loads and the
effects of buoyancy, and by means other than elevation.
Flood-proofing means any combination of structural and nonstructural additions, changes, or adjustments to
non-residential structures that reduces or eliminates flood damage to real estate or improved real property,
water and sanitary facilities, structures, and their contents by means other than elevation.
Flood-Related Erosion means the collapse or subsidence of land along the shore of a lake or other body of
water as a result of undermining caused by waves or currents of water exceeding anticipated cyclical levels or
suddenly caused by an unusually high water level in a natural body of water, accompanied by a severe storm,
or by an unanticipated force of nature, such as a flash flood or an abnormal tidal surge, or by some similarly
unusual and unforeseeable event which results in flooding.
Floodway. See “Regulatory Floodway.”
Floodway Fringe is that area of the floodplain lying on either side of a regulatory floodway where
encroachment may be permitted.
Functionally Dependent Use means a use which cannot perform its intended purpose unless it is located or
carried out in close proximity to water. The term includes only docking facilities, port facilities that are
necessary for the loading and unloading of cargo or passengers, and ship building and ship repair facilities, and
does not include long term storage or related manufacturing facilities.
Governing Body is the local governing unit (i.e., county or municipality) empowered to adopt and implement
regulations providing for the public health, safety, and general welfare of its citizenry.
Hardship means that the physical characteristics of the property in question are so unusual, exceptional, and
peculiar to the property that a variance regarding its use may be requested and granted. Mere economic or
financial hardship alone is not exceptional. Inconvenience, aesthetic considerations, physical handicaps,
personal preferences, or the disapproval of one’s neighbors likewise cannot, as a rule, be construed to qualify
as an exceptional hardship. All of these problems can be resolved through other means without granting a
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variance, even if the alternative is more expensive, requires the property owner to build elsewhere, or means
that the parcel must be put to a different use than originally intended.
Highest Adjacent Grade means the highest natural elevation of the ground surface immediately adjacent to a
structure prior to construction of the proposed walls of a structure.
Historic Structure means any structure that is:
A. Listed individually in the National Register of Historic Places (a listing maintained by the
Department of the Interior) or preliminarily determined by the Secretary of the Interior as meeting the
requirements for individual listing on the National Register;
B. Certified or preliminarily determined by the Secretary of the Interior as contributing to the historical
significance of a registered historic district or a district preliminarily determined by the Secretary to
qualify as a registered historic district;
C. Individually listed on the State of Arizona inventory of historic places, as approved by the Secretary
of the Interior; or
D. Individually listed on the Town of Oro Valley’s inventory of historic places and that has been
certified by an approved State of Arizona program, as determined by the Secretary of the Interior.
Levee means a human-made structure, usually an earthen embankment designed and constructed in accordance
with sound engineering practices, for the purpose of containing, controlling, or diverting the flow of water so
as to provide protection from temporary flooding.
Lowest Floor means the lowest floor of the lowest enclosed area including the basement (see “Basement”
definition) or crawl space under a manufactured home if it is not vented. An unfinished or flood resistant
enclosure, usable solely for parking of vehicles, building access, or storage in an area other than a basement
area is not considered to be the lowest floor of a structure; provided, that such enclosure is not built so as to
render the structure in violation of the applicable nonelevation design requirements of this chapter.
Manufactured Home means a structure, transportable in one or more sections, which is built on a permanent
chassis and is designed for use with or without a permanent foundation when attached to the required utilities.
The term “manufactured home” does not include a “recreational vehicle.”
Manufactured Home Park or Subdivision means a parcel (or contiguous parcels) of land divided into two
(2) or more manufactured home lots for rent or sale.
Market Value means the determination of the estimated cost to replace the structure in new condition and
adjusting that cost figure by the amount of depreciation that has accrued since the structure was constructed.
The cost of replacement of the structure shall be based on a square foot cost factor determined by reference to
a building cost estimating guide recognized by the building construction industry. The amount of depreciation
shall be determined by taking into account the age and physical deterioration of the structure and functional
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obsolescence as approved by the floodplain administrator, butadministrator but shall not include economic or
other forms of external obsolescence. Use of replacement costs or accrued depreciation factors different from
those contained in recognized building cost estimating guides may be considered only if such factors are
included in a report prepared by an independent professional appraiser and supported by a written explanation
of the differences. Alternatively, the market value is the valuation made by the Pima County Assessor’s Office.
Mean Sea Level means, for purposes of the National Flood Insurance Program, the National Geodetic Vertical
Datum (NGVD) of 1929, North American Vertical Datum of 1988 (NAVD ’88), or other datum to which base
flood elevations Base Flood Elevations shown on a community’s Flood Insurance Rate Map are referenced.
National Flood Insurance Program (NFIP) means a program administered by FEMA that makes Federally
backed flood insurance available for purchase by individuals that live in NFIP participating communities.
New Construction. For the purposes of determining insurance rates, structures for which the “start of
construction” commenced on or after the effective date of an initial flood insurance rate map or after December
31, 1974, whichever is later, and includes any subsequent improvements to such structures. For floodplain
management purposes, “new construction” means structures for which the “start of construction” commenced
on or after the effective date of a floodplain management regulation adopted by a community and includes any
subsequent improvements to such structures.
Obstruction includes, but is not limited to, any dam, wall, embankment, levee, dike, pile, abutment,
protection, excavation, channelization, bridge, conduit, culvert, structure, wire, fence, rock, gravel, refuse, fill,
structure, vegetation, or other material in, along, across, or projecting into any watercourse which may alter,
impede, retard, or change the direction and/or velocity of the flow of water, or which due to its location
influences its propensity to snare or collect debris carried by the flow of water, thereby reducing its likelihood
of being carried downstream as well as reducing the channel’s ability to convey flow.
One Hundred (100) Year Flood means the flood having a one percent (1%) chance of being equaled or
exceeded in any given year (see “Base Flood”).
Person means an individual or his their agent, firm, partnership, association or corporation, or agent of the
aforementioned groups, or the State of Arizona or its agencies or political subdivisions.
Program means the National Flood Insurance Program authorized by 42 U.S.C. 4001 through 4128, or as
authorized by subsequent Federal statutes.
Reach is a hydraulic engineering term to describe longitudinal segments of a stream or watercourse. A reach
will generally include the segment of the flood hazard area where flood heights are primarily controlled by
manmade or natural obstructions or constrictions. In an urban area, an example of a reach would be the
segment of a stream or watercourse between two (2) consecutive bridge crossings.
Recreational Vehicle means a vehicle that is:
A. Built on a single chassis;
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B. Four hundred (400) square feet or less in area, when measured at the largest horizontal projection;
C. Designed to be self-propelled or permanently towable by a light duty truck; and
D. Designed primarily not for use as a permanent dwelling but as temporary living quarters for
recreational, camping, travel, or seasonal use.
Regulatory Flood Elevation means an elevation that is one (1) foot above the calculated water surface
elevation of the base flood Base Flood.
Regulatory Floodplain or Flood-Prone Area means that portion of the geologic floodplain associated with a
watercourse, including its channel or any other floodplain or flood-prone area that would be inundated by the
base flood a 100-year-flood with a peak discharge of 100 cubic feet per second (cfs) or greater. It also means
areas which are subject to sheet flooding, special flood hazard areas Special Flood Hazard Areas, and those
areas mapped as floodplains/flood-prone on recorded subdivision plats or other flood hazard boundary maps.
Regulatory Floodway means the channel of a watercourse and the adjacent land areas that must be reserved in
order to discharge the base flood without cumulatively increasing the water surface elevation more than a
designated amount.
Remedy a Violation means to bring the structure or other development into compliance with State or local
floodplain management regulations, or, if this is not possible, to reduce the impacts of its noncompliance.
Ways that impacts may be reduced include protecting the structure or other affected development from flood
damages, implementing the enforcement provisions of this chapter, otherwise deterring future similar
violations, or reducing Federal financial exposure with regard to the structure or other development.
Repetitive Loss Structure means a structure, covered by a contract for flood insurance issued pursuant to the
National Flood Insurance Act, that has incurred flood-related damage on two (2) occasions during any ten (10)
year period ending on the date of the event for which a second claim is made, and for which the cost of
repairing the flood damage, on average, equaled or exceeded twenty-four percent (24%) twenty-five percent
(25%) of the market value of the structure at the time of each such flood event. In addition to the current claim,
the NFIP must have paid the previous qualifying claim.
Retention System means a type of flood control system that stops the downstream progress of flood water by
employing methods of total containment which generally involve creation of storage areas that incorporate
infiltration devices, such as dry wells, to dispose of stored waters, principally by percolation over some
specified period of time, thereby eliminating basin contributions to downstream flood peaks or flood volumes.
Riverine means relating to, formed by, or resembling a river (including tributaries), stream, brook, etc.
Sheet Flow Area. See “Area of Shallow Flooding.”
Special Flood Hazard Area (SFHA) means an area in the floodplain subject to a one percent (1%) or greater
chance of flooding in any given year. A SFHA may be designated on a FIRM as a Zone A, AO, AE, or AH for
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the base flood, as well as for areas that the Town Engineer, using the best available data, has determined may
be subject to a flood hazard during the base flood Base Flood.
Start of Construction includes substantial improvement or other proposed new development, and means the
date the building permit was issued, provided the actual start of construction, repair, reconstruction,
rehabilitation, addition, placement, or other improvement was within the time period when the permit was
active. The “actual start” means either the first placement of permanent construction of a structure on a site,
such as the pouring of slab or footings, the installation of piles, the construction of columns, or any work
beyond the stage of excavation; or the placement of a manufactured home on a foundation. Permanent
construction does not include land preparation such as the installation of streets and/or walkways, the
installation on the property of accessory structures, such as garages or sheds not occupied as dwelling units or
not part of the main structure. For a substantial improvement, the “actual start of construction” means the first
alteration of any wall, ceiling, floor or other structural part of a structure, whether or not that alteration affects
the external dimensions of the structure.
Structure means any building or containment unit that is constructed or erected, the use of which requires
location on the ground or attachment to a foundation having a location on the ground. This includes a gas or
liquid storage tank or a manufactured home.
Substantial Damage means damage of any origin, cumulatively tracked over a period of ten (10) years,
sustained by a structure whereby the cost of restoring the structure to its before-damaged condition would
equal or exceed forty-nine percent (49%) of the market value of the structure before the damage occurred.
“Substantial damage” also means flood-related damage sustained by a structure on two (2) separate occasions
during a rolling ten (10) year period for which the cost of repairs at the time of each such flood event, on the
average, equals or exceeds twenty-four percent (24%) of the market value of the structure before the damage
occurred. damage of any origin sustained by a structure whereby the cost of restoring the structure to its
before damaged condition would equal or exceed 50 percent of the market value of the structure before
the damage occurred.
Substantial Improvement means any reconstruction, rehabilitation, addition, or other improvement of a
structure, cumulatively tracked over a period of ten (10) years, the cost of which equals or exceeds forty-nine
percent (49%) of the market value of the structure before the start of construction of the improvement. This
term includes structures that have incurred repetitive loss or substantial damage, regardless of the actual repair
work performed. The term does not, however, include either: reconstruction, rehabilitation, addition, or other
improvement to a structure, the total cost of which equals or exceeds 50 percent of the market value of the
structure before the "start of construction" of the improvement. This term includes structures which have
incurred "substantial damage", regardless of the actual repair work performed. The term does not,
however, include either:
A. Any project for improvement of a structure to correct existing violations of state or local health,
sanitary, or safety code specifications which have been identified by the local code enforcement
official and which are the minimum necessary to assure safe living conditions; or
B. Any alteration of a "historic structure", provided that the alteration will not preclude the structure's
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continued designation as a "historic structure”.
A. Any project for improvement of a structure to correct existing violations of State or local health, sanitary,
or safety code specifications which have been identified by the local code enforcement official, and which are
the minimum necessary to assure safe living conditions, or
B. Any alteration of a historic structure; provided, that the alteration will not preclude the structure’s
continued designation as a historic structure.
Variance means a grant of relief from the requirements of this chapter that is granted by the Floodplain
Administrator or the Floodplain Board (for FEMA floodplains) upon a finding that strict enforcement of the
provisions would cause undue hardship owing to circumstances unique to the individual property for which the
variance is granted, and not caused by the applicant for said variance.
Violation means the failure of a structure or other development to be fully compliant with the Town of Oro
Valley floodplain management regulations. A structure or other development without the elevation certificate,
other certifications, or other evidence of compliance required by this chapter, is presumed to be in violation
until such time as such documentation is provided. Violation also means unauthorized construction, grading,
encroachment, diversion, or lack of maintenance of private drainage structures.
Water Surface Elevation means the height, in relation to the National Geodetic Vertical Datum (NGVD) of
1929 or the North American Vertical Datum (NAVD) of 1988 (or other datum, where specified), of floods of
various magnitudes and frequencies in the floodplains of riverine areas.
Watercourse means a lake, river, creek, stream, wash, arroyo, channel, or other topographic feature on or over
which waters flow at least periodically. “Watercourse” includes specifically designated areas in which
substantial flood damage may occur, including regulatory floodplains as designated by FEMA or the Town of
Oro Valley. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
Article 17-3
GENERAL PROVISIONS
Sections:
17-3-1 Lands to Which This Chapter Applies
17-3-2 Basis for Establishing the Regulatory Floodplain Areas
17-3-3 Compliance
17-3-4 Abrogation and Greater Restrictions
17-3-5 Interpretation
17-3-6 Statutory Exceptions
17-3-7 Floodplain Violations
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17-3-8 Abatement of Violations
17-3-9 Unlawful Acts
17-3-10 Remedies
17-3-11 Severability
17-3-12 Warning and Disclaimer of Liability
17-3-1 Lands to Which This Chapter Applies.
This chapter shall apply to all regulatory floodplain areas Special Flood Hazard Areas within the corporate
limits of the Town of Oro Valley. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-3-2 Basis for Establishing the Regulatory Floodplain Areas.
The regulatory floodplain areasSpecial Flood Hazard Areas identified by the Federal Insurance and Mitigation
Administration (FIMA) of the Federal Emergency Management Agency (FEMA) in a scientific and
engineering report entitled The Flood Insurance Study (FIS) for Pima County, Arizona and Incorporated
Areas, revised June 16, 2011 September 28, 2012, with accompanying Flood Insurance Rate Maps (FIRMs)
dated June 16, 2011, and all subsequent amendments and/or revisions, are hereby adopted by reference and
declared to be a part of this chapter. This Flood Insurance Study (FIS) and attendant mapping may be
supplemented by studies for other areas that allow implementation of this chapter are the minimum area of
applicability of this Ordinance and may be supplemented by studies for other areas which allow
implementation of this Ordinance and which are recommended to the Floodplain Board by the Floodplain
Administrator. The Floodplain Board, within the incorporated limits of the Town of Oro Valley, shall require
developers of land to delineate, within areas where development is ongoing or imminent, floodplains
consistent with the criteria developed by FEMA, the Arizona Director of Water Resources, and the Town
Engineer, pursuant to the Town’s adopted Drainage Criteria Manual. The Flood Insurance Study, and FIRMs
are on file at the Town of Oro Valley.
Additionally, areas determined by the Town Engineer, including floodplains/flood-prone areas identified on
previously recorded subdivision plats (and those recorded hereafter), are also hereby adopted, by reference,
and declared a part of this chapter.
A. Regulatory floodplains shall be subject to the following regulations, except as hereinafter provided:
1. No person or persons shall construct any structure which will divert, retard, or obstruct the flow of
water in any stream, watercourse, or regulatory floodplain area without having secured all necessary
permits from any governmental agency from which approval is required by Federal or State or local law,
and said permits or copies thereof shall be provided to the Floodplain Administrator for review.
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2. No person shall construct any structure that will divert, retard, or obstruct the flow of water in any
stream, watercourse, or regulatory floodplain area without securing written authorization in the form of a
Floodplain Use Permit from the Town of Oro Valley, except as exempted in Section 17-3-6.
3. The FIS and areas shown on FIRMs together with floodplains associated with washes and/or sheet
flow areas having one hundred (100) year peak discharges of fifty (50) cfs or more, are the minimum
areas of applicability of this chapter, and may be supplemented by studies for other areas that allow
implementation of this chapter. Applicants for development in the Town of Oro Valley shall delineate
floodplains consistent with criteria developed by FEMA, the Town Engineer, and/or pursuant to the
Town’s adopted Drainage Criteria Manual.
4. All property in the regulatory floodplains, except that covered by statutory exceptions, shall be
governed according to the provisions herein.
5. Any use of land otherwise authorized by law shall be permitted, provided such use meets the
minimum standards of the regulations hereinafter set forth.
B. Elevation and Boundary Refinements.
1. The determination of elevations (water surface, lowest finished floor, and adjacent land) and
regulatory floodway and regulatory floodplain boundaries is an engineering function with calculations
and decisions made in accordance with the concepts and policies set forth in this chapter. The best
technical data available shall be used for such calculations and decisions. Initial determinations shall be
based on floodplain information reports of the Pima County Flood Control District, U.S. Corps of
Engineers, U.S. Bureau of Reclamation, U.S. Geological Survey, and/or other general data that are
pertinent for the conditions of the streams or the watercourses at the time the data are obtained.
2. Additional and more detailed technical analysis will, from time to time, become available through
private or governmental studies and activities. These data will permit refinements in the elevations and
boundaries of regulatory floodway and regulatory floodplains in the respective reaches of the streams or
watercourses.
3. Whenever such additional data become available and it seems desirable to make refinements, i.e.,
Letter of Map Amendments (LOMAs) or Letter of Map Revisions (LOMRs), such refinements or
revisions may be made at the request of the property owners or developers or by the Town Engineer. The
necessary engineering calculations shall be made for the property owner or developer by an Arizona
registered professional civil engineer (at the owner’s/developer’s expense) in conformance with
requirements of this chapter, the FEMA, and the Arizona Department of Water Resources. These findings
will need approval of the Town Engineer. Following the Town’s approval of these refinements to
regulatory floodplain areas identified on FIRMs, the property owner shall have calculations and forms
forwarded to FEMA for review and approval.
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4. The Town Engineer or his/her duly designated representative shall have the authority and
responsibility to revise and refine elevations and boundaries of regulatory floodways and regulatory
floodplains whenever such revisions and refinements are for the purpose and in accordance with the
conditions set forth in Sections 17-4-3(B)(1)(d), 17-5-8(B)(3), 17-5-8(B)(4), and 17-5-8(B)(5).
a. The Flood Insurance Rate Map for Pima County and Incorporated Areas shall be revised to show
the refined area boundaries and/or elevations.
b. The Town Engineer shall notify the owner of each property for which area boundaries and/or
elevations have been revised or refined, as well as those owners of adjoining property immediately
upstream and downstream, by first class mail following a duly noticed public hearing on the property
involved.
c. An appeal to the Floodplain Board may be taken by any person aggrieved, in accordance with
Article 17-6. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-3-3 Compliance.
All development of land, construction of residential, commercial, or industrial structures, or future
development within delineated floodplain areas is subject to the terms of this chapter and any other applicable
Regulations. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-3-4 Abrogation and Greater Restrictions.
The provisions of this chapter are not intended to interfere with, abrogate, or annul any ordinance, rule,
regulations, or permit previously adopted or issued, and not be in conflict with any provision of this chapter or
any regulation that shall be adopted or issued pursuant to law relating to the use of structure or ordinance not in
conflict with this chapter; nor is it intended by this chapter to interfere with or abrogate or annul any easement,
covenant, or other agreement between parties, except when this chapter imposes a greater restriction, this
chapter shall control. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-3-5 Interpretation.
In the interpretation and application of this chapter, all provisions shall be:
A. Considered as minimum requirements;
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B. Liberally constructed in favor of the governing body; and
C. Deemed neither to limit nor repeal any other powers granted under State statutes. ((O)17-04, 04/05/2017;
(O)05-35, 10/05/2005)
17-3-6 Statutory Exceptions.
A. In accordance with ARS § 48-3609(H) 48-3609(I), unless expressly provided this and any regulation
adopted pursuant to this article do not affect:
1. Existing legal uses of property or the right to continuation of such legal use. However, if a
nonconforming use of land or a structure is discontinued for twelve (12) months or destroyed to the extent
of forty-nine percent (49%) fifty percent (50%) or more of its market value, as determined by a
competent appraiser, or the valuation made by the Pima County Assessor’s Office, any further use shall
comply with this article and regulations of the Town of Oro Valley.
2. Reasonable repair or alteration of property for the purposes for which the property was legally used on
August 3, 1984, or any regulations affecting such property takes effect, except that any alteration,
addition, or repair to a nonconforming structure which would result in increasing its flood damage
potential by forty-nine percent (49%) fifty percent (50%) or more shall be either flood-proofed or
elevated to or above the regulatory flood elevation.
3. Reasonable repair of structures constructed with the written authorization required by ARS § 48-3613.
4. Facilities constructed or installed pursuant to a certificate of environmental compatibility Certificate
of Environmental Compatibility issued pursuant to ARS Title 40, Chapter 2, Article 6.2.
B. Before the following types of construction authorized by this section A.R.S. § 48-3613(B) may begin,
the responsible person must submit grading plans and a grading permit application for review and comment
pursuant to A.R.S. § 48-3613(C) . The applicant must obtain necessary plan and permit approvals, as well as
meet requirements pursuant to the Oro Valley Zoning Code Revised, Town of Oro Valley Drainage Criteria
Manual, and any other applicable Town standards:
1. The construction of bridges, culverts, dikes, and other structures necessary for the construction of
public highways, roads, and streets intersecting or crossing a watercourse.
2. The construction of storage dams for watering livestock or wildlife, structures on banks of a
watercourse to prevent erosion of, or damage to, adjoining land, if the structure will not divert, retard or
obstruct the natural channel of the watercourse, or dams for the conservation of floodwaters as permitted
by ARS Title 45, Chapter 6.
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3. The construction of tailing dams and waste disposal areas for use in connection with mining and
metallurgical operations. This subsection does not exempt those sand and gravel operations that will
divert, retard or obstruct the flow of waters in any watercourse from complying with, and acquiring
authorization from, the Town Engineer or the Floodplain Board pursuant to regulations adopted by the
Floodplain Board under this article.
4. Other construction, if it is determined by the Town Engineer that a Floodplain Use Permit is
unnecessary.
5. Any flood control district, county, city, town, or other political subdivision from exercising powers
granted to it under ARS Chapter 21, Article 1.
6. The construction, by a public agency or political subdivision, of streams, waterways, lakes, and other
auxiliary facilities in conjunction with development of public parks and recreation facilities.
7. The construction and erection of poles, towers, foundations, support structures, guy wires, and other
facilities related to power transmission as constructed by any utility, whether a public service corporation
or a political subdivision.
C. In accordance with A.R.S. § 48-3613(O), In in addition to other penalties or remedies otherwise provided
by law, the State of Arizona, a political subdivision thereof, or a person who may be damaged or has been
damaged as a result of the unauthorized diversion, retardation, or obstruction of a watercourse has the right to
go through an Administrator/Board to commence, maintain, and prosecute any appropriate action or pursue
any remedy to enjoin, abate, or otherwise prevent any person from violating or continuing to violate this
section or regulations adopted pursuant to this article A.R.S. Title 48, Chapter 21, Article 1. If a person is
found to be in violation of this section, the Administrator/Board shall require the violator either to comply with
this section, if authorized by the Floodplain Board for FEMA regulated floodplains (the Town Engineer for
non-FEMA regulated floodplains), or to remove the obstruction and restore the watercourse to its original
state. The court may also award such monetary damages as are appropriate to the injured parties resulting from
the violation, including reasonable costs and attorney fees. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-3-7 Floodplain Violations.
A. Declaration of Public Nuisance. All development located or maintained within any regulatory floodplain
area after August 8, 1973, in violation of this chapter, and without written authorization from the Floodplain
Board for FEMA regulated floodplains (the Town Engineer for non-FEMA regulated floodplains), is a public
nuisance per se, and may be abated, prevented or restrained by action of the Floodplain Board. ((O)17-04,
04/05/2017; (O)05-35, 10/05/2005)
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The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
17-3-8 Abatement of Violations.
Upon discovery of a violation to this chapter, the Floodplain Administrator shall either:
A. Take any necessary action to effect the abatement of such violation; or
B. Order the owner of the property upon which the violation exists to provide whatever additional
information may be required for determination by the Floodplain Administrator. Such information must be
provided to the Floodplain Administrator within thirty (30) days of such order. Within thirty (30) days, the
Floodplain Administrator shall either order the abatement of said violation or shall grant a variance in
accordance with the provisions of Section 17-6-4; or
C. For FEMA regulated floodplains, submit to the Administrator of the Federal Insurance Administration
the Federal Emergency Management Agency a declaration for denial of insurance, stating that the property is
in violation of a cited State or local law, regulation or ordinance, pursuant to Section 1316 of the National
Flood Insurance Act of 1968, and as amended. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-3-9 Unlawful Acts.
A. It is unlawful for any person to divert, retard or obstruct the flow of waters in any watercourse whenever it
creates a hazard to life or property without securing the written authorization required by ARS § 48-3613.
Where the watercourse is a delineated floodplain, it is unlawful to excavate or build any structure affecting the
flow of waters without securing written authorization required per ARS § 48-3613. It is unlawful for a person
to engage in any development or to divert, retard, or obstruct the flow of waters in a watercourse if it creates a
hazard to life or property without securing the written authorization required by A.R.S. § 48-3613. Where the
watercourse is a delineated floodplain, it is unlawful to engage in any development affecting the flow of waters
without securing written authorization required by A.R.S. § 48-3613.
B. It is unlawful for any person to neglect maintenance responsibilities on private drainage improvements.
C. Any person violating the provisions of this section shall be subject to appeal and variance procedures
pursuant to Article 17-6, and penalties pursuant to Article 1-8, Penalties, Oro Valley Town Code. ((O)17-04,
04/05/2017; (O)05-35, 10/05/2005)
D. The Town may issue a written Notice to Correct to any person who has violated or is in violation of this
section.
E. Failure to comply with actions described in and required by the Notice to Correct may result in a Notice of
Violation and/or Stop Work Order. The written notice shall state the nature of the violation, the corrective action
required, the time frame for the corrective action, and penalties for continued noncompliance.
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The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
17-3-10 Remedies.
All remedies provided for herein shall be cumulative and not exclusive. The conviction and punishment of any
person hereunder shall not relieve such person from the responsibility to correct prohibited conditions or to
remove prohibited structures, obstructions, or improvements; nor prevent the enforcement, correction, or
removal thereof. In addition to the other penalties or remedies provided in this article, the State of Arizona, any
political subdivision thereof, or any person who may be damaged as a result of the diversion, retardation, or
obstruction of a watercourse shall have the right to commence, maintain, and prosecute any appropriate action
or pursue any remedy to enjoin, abate, or otherwise prevent any person from violating or continuing to violate
any provision of this chapter. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-3-11 Severability.
This chapter, and its various parts thereof, is hereby declared to be severable. Should any section of this
chapter be declared by the courts to be unconstitutional or invalid, such decision shall not affect the validity of
the chapter as a whole, or any portion thereof, other than the section so declared to be unconstitutional or
invalid. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-3-12 Warning and Disclaimer of Liability.
The degree of flood protection required by this chapter is considered reasonable for regulatory purposes, and is
based on scientific and engineering considerations. Larger floods can and will occur on rare occasions. Flood
heights may be increased by manmade or natural causes. This chapter does not imply that land outside the
regulatory floodplain areas or uses permitted within such areas will be free from flooding or flood damages.
This chapter shall not create liability on the part of the Town of Oro Valley, any officer or employee thereof,
the State of Arizona, the Federal Insurance Administration, or the Federal Emergency Management Agency,
for any flood damages that result from reliance on this chapter or any administrative decision lawfully made
hereunder. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
Article 17-4
ADMINISTRATION
Sections:
17-4-1 Establishment of Floodplain Use Permits
17-4-2 Enforcement and Inspection
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The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
17-4-3 Duties of Floodplain Administrator and Use Permit Procedures
17-4-4 Designation of the Floodplain Administrator
17-4-1 Establishment of Floodplain Use Permits.
A. Responsibility For Permits. It shall be the duty of the Town Engineer, and all departments, officials, and
public employees vested with the duty or authority to issue permits or licenses, to enforce the provisions of this
chapter; and no such license or permit shall be issued for uses or building where the same would be in conflict
with the provisions of this chapter. Any such license or permit, if issued in conflict with the provisions of this
chapter, shall be null and void.
B. Floodplain Use Permits. It shall be unlawful to erect, construct, reconstruct, alter, or change the use of any
structure within any regulatory floodplain area covered by this chapter without first applying for and obtaining
a Floodplain Use Permit from the Town Engineer.
C. Application for Floodplain Use Permit. Application for a Floodplain Use Permit shall be made on forms
furnished by the Town Engineer, and must include, without limitation, plans in duplicate drawn to scale
showing the nature, location, dimensions, and elevation of the areas in question; existing or proposed
structures including walls, bank protection, fill, storage of materials, drainage facilities; and the location of the
foregoing. Specifically, the following information is required:
1. Proposed elevation, in relation to mean sea level, of the lowest floor (including basement) of all
structures. In a designated Zone AO, elevation of existing highest adjacent natural grade and proposed
elevation of lowest floor of all structures must be obtained;
2. Proposed elevation, in relation to mean sea level, to which any structure will be flood-proofed;
3. Certification by an Arizona registered professional civil engineer or an Arizona registered
professional architect that the flood-proofing methods for any nonresidential structure meet the
flood-proofing criteria in Section 17-5-1(C);
4. Base flood elevation data shall be provided for subdivisions or other developments greater than fifty
(50) lots or five (5) acres, whichever is the lesser; and
5. Description of the extent to which any watercourse will be altered or relocated as a result of proposed
development. Each such application shall be accompanied by an application fee, as set forth by the Town,
payable to the Town of Oro Valley. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
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The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
17-4-2 Enforcement and Inspection.
A. Enforcement. It shall be the duty of the Town Engineer, through his/her duly appointed Floodplain
Administrator and officials of the Town otherwise charged with the enforcement of the law, to enforce this
chapter and all of the provisions of the same.
B. Inspections. Inspections shall be made by the Town Engineer or by a duly appointed Floodplain
Administrator.
C. Cooperation. The Town Floodplain Administrator may request, and shall receive so far as may be
necessary in the discharge of his/her duties, the assistance and cooperation of all departments, agencies,
officials, and public employees vested with the duty or authority to issue permits, licenses, or to enforce the
regulations of this chapter.
D. Town of Oro Valley Administration. Hydrologic, hydraulic, and related floodplain regulations, as well as
engineering matters pertaining to the administration and direction of this chapter, shall be referred to the Town
of Oro Valley Town Engineer or his/her designated representative, who shall be responsible for such reviews,
advice, and recommendations.
E. Cooperation Agreements and Consultants. The Floodplain Administrator, through the applicable
procurement and/or intergovernmental agreement procedures, may retain consultants and experts; and may
enter into cooperative agreements for the delineation of floodplains and floodways as well as for such other
assistance and guidance considered appropriate and necessary to obtain maximum reasonable protection and
benefits under this chapter. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-4-3 Duties of Floodplain Administrator and Use Permit Procedures.
A. The Floodplain Administrator shall issue Floodplain Use Permits required by this section.
B. The following procedure shall be used by the Floodplain Administrator in considering issuance of
Floodplain Use Permits.
1. Upon receiving an application for a Floodplain Use Permit involving the use of fill, construction of
structures, or the storage of materials, and prior to rendering a decision thereon the Floodplain
Administrator may:
a. Require the applicant to submit, where applicable, plans in triplicate drawn to scale showing the
nature, location, dimensions, and elevations of the lot; existing or proposed structures, fill, storage of
materials, flood-proofing measures; and the relationship of the above to the location of the channel,
regulatory floodway, the regulatory floodplain with base flood elevations, the proposed project in
relation to flood heights and velocities, and the plans for flood protection. The applicant shall
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The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
provide a new delineation of all regulatory floodplains affected by the project. The new delineation
and reports shall be prepared in conformance with FEMA requirements and this chapter. The
delineation shall show pre- and post-project floodplain limits and water surface elevations upstream,
adjacent, and downstream of the project.
b. Require, where circumstances necessitate more detailed information, the applicant to furnish as
much of the following additional information as is deemed necessary by the Floodplain
Administrator for the evaluation of the effects of the proposed use upon flood flows and the
consideration of other factors necessary to render a decision on suitability of the proposed use:
i. A typical valley cross-section showing the floodway, floodway fringe area, and the
floodplain of the watercourse; elevation of land areas adjoining each side of the channel;
cross-sectional areas to be occupied by the proposed development; and high water information;
ii. A plan (surface view) showing elevations or contours of the ground; pertinent structure, fill
or storage elevations; size, location, and spatial arrangement of all proposed and existing
structures on the site; location and elevations of streets, water supply, sanitary facilities;
photographs showing existing land uses and vegetation upstream and downstream, and soil
types, as well as other pertinent information;
iii. A profile showing the slope of the bottom of the channel or flow line of the watercourse;
iv. Specifications for building construction and materials, flood-proofing, filling, dredging,
grading, channel improvement, storage of materials, water supply, and sanitary facilities.
c. Ensure that the proposed development does not adversely affect the carrying capacity of channels
at locations where base flood elevations have been determined but a floodway has not been
designated.
d. For FEMA regulated floodplains, may require the applicant to submit appropriate (e.g., CLOMR,
CLOMR-F, LOMR, etc.) applications, forms, and information to FEMA for review and approval. A
Floodplain Use Permit shall not be issued by the Town of Oro Valley until after receiving upon
acknowledgement from FEMA of the acceptance of the CLOMR. Additionally, final building permit
inspections shall not be made, and nor shall certificates of occupancy be given, until after receiving
acknowledgement from FEMA that the LOMR has become effective.
e. Ensure other related State of Arizona and Federal permits have been issued.
2. No permit shall be issued for any development that is not in conformance with this chapter, FEMA
regulations, or some other provision of law relating to such development. A Floodplain Use Permit may
be denied if the proposed development constitutes a danger or hazard to life or property.
C. The Floodplain Administrator shall be responsible for the following duties:
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The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
1. Obtain and maintain for public inspection and make available the following:
a. Certification of the regulatory flood elevation required in Sections 17-5-1(C)(1), 17-5-1(C)(3)
17-5-1(C)(2), and 17-5-5;
b. The Zone AO certification required in Section 17-5-1(C)(2);
c. The flood-proofing certification required in Section 17-5-1(C)(3);
d. The certified opening elevation required in Section 17-5-1(C)(4);
e. Review and maintain records of all development permits for improvements and/or damages to
existing structures to determine if the application of the substantial improvement rules applies,
including establishing a definition of market value determination and verifying that the estimated
improvement and/or repair costs are less than forty-nine percent (49%) of the market value of the
structure, calculated over a ten (10) year period from the initial application for improvement or repair
of damages. The substantial improvement rules shall apply to the following:
i. Qualifying structures located in regulatory floodplains as designated by FEMA; those areas
mapped as floodplains/flood-prone on recorded subdivision plats; or on flood hazard boundary maps
prepared by, or for, the Floodplain Administrator. Qualifying structures shall also satisfy one of the
following two (2) additional conditions:
(A) Pre-FIRM structures constructed before the date of the initial Flood Insurance Rate Map issued
for the Town dated December 4, 1979; or
(B) Legal nonconforming structures constructed on, or after, December 4, 1979, in compliance with
the effective FIRM at the time of construction, and in compliance with the terms and conditions of
the written authorization in effect at the time of construction;
Review all development permits for improvements and/or damages to existing structures to
determine if the application of the substantial improvement rules apply, including establishing a
definition of market value determination and verifying that the estimated improvement and/or
repair costs are less than 50% of the market value of the structure.
f. Certification of elevation for subdivisions required by Section 17-5-4(E);
g. Certification for floodway encroachments required by Section 17-5-7(A);
h.. Records of all variance actions, including justification for their issuance required by Section
17-6-3(C).
2. Whenever a watercourse is to be altered or relocatedNotification of other entities:
a. Notify adjacent communities and ADWR prior to such alteration or relocation of a watercourse,
and submit evidence of such notification to FEMA through appropriate notification means; and
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The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
b. Require that the flood carrying capacity of the altered or relocated portion of said watercourse be
maintained.
3. Within one hundred twenty (120) days after completion of construction of any flood control protective
works which changes the rate of flow during the flood or the configuration of the floodplain upstream or
downstream from or adjacent to the project, the person or agency responsible for installation of the project
shall provide to the governing bodies of all jurisdictions affected by the project a new delineation of all
floodplains affected by the project. The new delineation shall be done according to the criteria adopted by
the ADWR.
4. Advise the district of Pima CountyPima County Regional Flood Control District and any adjunct
jurisdiction having responsibility for floodplain management in writing and provide a copy of a
development plan of all applications for Floodplain Use Permits or variances to develop land in a
floodplain or floodway within one (1) mile of the corporate limits of the Town of Oro Valley, Arizona.
Also, advise the district of Pima CountyPima County Regional Flood Control District in writing and
provide a copy of any development plan of any major development proposed within a floodplain or
floodway, which could affect floodplains, floodways or watercourses within the district’s area of
jurisdiction. Written notice and a copy of the plan of development shall be sent to the district no later than
three (3) working days after having been received by Town of Oro Valley.
5. Notify FEMA of acquisition by means of annexation, incorporation or otherwise, of additional areas
of jurisdiction.
6. A community’s base flood elevations may increase or decrease resulting from physical changes
affecting flooding conditions. As soon as practicable, but not later than six (6) months after the date such
information becomes available, a community shall notify FEMA of the changes by submitting technical
or scientific data in accordance with Volume 44 Code of Federal Regulations Section 65.3. Such a
submission is necessary so that upon confirmation of those physical changes affecting flooding
conditions, risk premium rates and floodplain management requirements will be based upon current data.
7. Use of Other Base Flood Data. When base flood elevation data has not been provided in accordance
with Section 17-3-2 (Basis for Establishing the Regulatory Floodplain Areas), the Floodplain
Administrator shall obtain, review and reasonably utilize any base flood elevation data available from a
Federal, State, or other source, in order to administer Section 17-5-1 (Standards for Construction). Any
such information shall be consistent with the requirements of the Federal Emergency Management
Agency and the Director of the Arizona Department of Water Resources and may be submitted to the
Floodplain Board for adoption.
8. Make map interpretations, where needed, as to the exact location of the boundaries of the special
flood hazard areas (e.g., where there appears to be a conflict between a mapped boundary and actual field
conditions). The person contesting the location of the boundary shall be given a reasonable opportunity to
appeal the interpretation as provided in Article 17-6 (Appeal and Variance Procedures).
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The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
9. Take remedial actions on violations of this chapter as required in Section 17-3-8 (Abatement of
Violations). ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-4-4 Designation of the Floodplain Administrator.
The Town Engineer or his/her designee is hereby appointed to administer, implement, and enforce this chapter
and guidelines set forth in this article by processing Floodplain Use Permits in accordance with its provisions.
((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
Article 17-5
PROVISIONS FOR FLOOD HAZARD REDUCTION
Sections:
17-5-1 Standards of Construction
17-5-2 Standards for Storage of Materials and Equipment
17-5-3 Standards for Utilities
17-5-4 Standards and Submittal Requirements for Subdivisions
17-5-5 Standards for Manufactured Homes
17-5-6 Standards for Recreational Vehicles
17-5-7 Floodways
17-5-8 Floodway Fringe Area Requirements
17-5-9 Flood Related Erosion-Prone Area
17-5-1 Standards of Construction.
In all regulatory floodplain areas, the following standards are required:
A. Anchoring.
1. All new construction and substantial improvements shall be anchored to prevent flotation, collapse, or
lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the
effects of buoyancy.
2. All manufactured homes shall meet the anchoring standards of Section 17-5-5.
B. Construction Materials and Methods.
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The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
1. All new construction and substantial improvements shall be constructed with materials and utility
equipment resistant to flood damage.
2. All new construction and substantial improvements shall be constructed using methods and practices
that minimize flood damage.
3. All new construction, substantial improvements, and other proposed new development shall be
constructed with electrical, heating, ventilation, plumbing, and air conditioning equipment, as well as
other service facilities that are designed and/or located so as to prevent water from entering or
accumulating within the components during conditions of flooding.
4. Within Zones AH or AO, adequate drainage paths around structures on slopes are required to guide
floodwaters around and away from proposed structures.
C. Elevation and Flood-Proofing.
1. New construction and substantial improvement of any structure shall have the lowest floor, including
basement, elevated at or above the regulatory flood elevationRegulatory Flood Elevation. In areas without
a detailed study but within regulatory floodplain boundaries, the applicant shall have an Arizona
registered professional civil engineer prepare a detailed study to determine the depth of the regulatory
flood. Nonresidential structures may meet the standards in Section 17-5-1(C)(3). Upon the completion of
the structure, the elevation of the lowest floor including basement, shall be certified by an Arizona
registered professional civil engineer or an Arizona registered professional land surveyor, and provided to
the Floodplain Administrator and the Town Building Official.
2. New construction and substantial improvement of any structure in Zone AO shall have the lowest
floor, including basement, higher than the highest adjacent grade at least one (1) foot higher than the
depth number on the FIRM, or at least two (2) feet if no depth number is specified. Nonresidential
structures may meet the standards in Section 17-5-1(C)(3). Upon completion of the structure an Arizona
registered professional civil engineer shall certify to the Floodplain Administrator that the elevation of the
structure meets this standard.
3. Nonresidential construction and new and substantial improvement of any structure shall either be
elevated in conformance with Section 17-5-1(C)(3) or 2, or together with attendant utility and sanitary
facilities:
a. Be flood-proofed so that below the regulatory flood elevation the structure is watertight with
walls substantially impermeable to the passage of water;
b. Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects
of buoyancy; and
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The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
c. Be certified by an Arizona registered professional civil engineer or an Arizona registered
professional architect that the standards of this subsection are satisfied. Such certifications shall be
provided to the Floodplain Administrator and the Town Building Official.
4. Require, for all new construction and substantial improvements of nonresidential structures, that have
fully enclosed areas below the regulatory flood elevation that are useable solely for parking of vehicles,
building access, or storage in an area other than a basement, and which are subject to flooding, shall be
constructed of flood resistant materials to the regulatory flood elevation, have all service facilities
elevated at or above the regulatory flood elevation, and be designed to automatically equalize hydrostatic
flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs for meeting this
requirement must either be certified by an Arizona Registered Professional Civil Engineer or an Arizona
registered professional architect or meet or exceed the following minimum criteria:
a. A minimum of two (2) openings, on different sides of each enclosed area, shall be provided
having a total net area of not less than one (1) square inch for every square foot of enclosed area
subject to flooding.
b. The bottom of all openings shall be no higher than one (1) foot above grade.
c. Openings may be equipped with screens, louvers, valves, or other coverings or devices, provided
that they permit the automatic entry and exit of floodwaters.
5. Manufactured homes shall meet the standards in Section 17-5-5. ((O)17-04, 04/05/2017; (O)05-35,
10/05/2005)
17-5-2 Standards for Storage of Materials and Equipment.
A. The storage or processing of materials is prohibited if they are, in time of flooding: buoyant, flammable,
explosive, or could be noxious, deadly, or injurious to human, animal, or plant life.
B. Storage of other material or equipment may be allowed if they are not subject to major damage by floods,
or if they are firmly anchored to prevent flotation, or if they are readily removable from the area within the
time available after flood warning. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-5-3 Standards for UtilitiesWater Supply and Waste Disposal Systems.
A. All new or replacement water supply and sanitary sewage systems shall be designed to minimize or
eliminate infiltration of floodwaters into the system and discharge from systems into floodwaters.
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B. On-site waste disposal systems shall not be installed wholly or partially in a regulatory floodway, erosion
setback, or as established by ADEQ, whichever is most restrictive. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-5-4 Standards and Submittal Requirements for Subdivisions.
A. All subdivision proposals shall be consistent with the need to minimize flood damage.
B. All subdivision proposals (also referred to as a final site plan) shall have all public utilities and facilities,
including but not limited to sewer, gas, electrical, and water systems located and constructed to minimize flood
damage.
C. All subdivisions shall provide adequate drainage to reduce exposure to flood hazards (See adopted
drainage Criteria Manual).
D. Suitability of the Land. Land that has been found by the Floodplain Board to be unsuitable for
development with permanent structures based on hydrological and engineering studies of flooding can be
platted and used for only open space and greenbelt uses such as those identified in Section 17-5-7(B)(1). This
includes land which is:
1. Physically unsuitable because of flooding, poor drainage, and other features which may endanger
health, life, or property, aggravate erosion, increase the flood hazard; or increase the burden imposed on
the community, its governmental units, and its citizens;
2. Subject to flooding because of its proximity to the stream or watercourse; or because of low elevation.
In applying this provision, the Floodplain Board, with technical support and recommendations from the
Town Engineer, shall consider:
a. Land subject to flooding by the base flood shall not be platted for residential occupancy, or
building sites, or for any other uses that may increase the flood hazard or endanger health, life, or
property, unless each lot contains a building site that meets requirements set forth below, in
subsections (G) and (H) of this section, and within other pertinent sections of this chapter;
b. Fill shall not be used to raise land within the regulatory floodway. In other areas subject to
flooding by the base flood, fill may be used; provided, that the proposed fill does not restrict the flow
of water and increase flood heights or velocities in the regulatory floodway, according to the same
standards established in Section 17-5-8, and provided that compensatory flood storage is provided.
E. Flood Situation to Be Shown on Plat. Plats submitted shall show the following:
1. Tentative development plans and preliminary development plans (plats) shall show the location, by
survey, of watercourses, channels, irrigation laterals, private ditches, culverts, lakes, or other water
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features, including direction of flow, water level elevations, and the location and extent of areas subject to
frequent inundation;
2. All preliminary subdivision proposals shall identify the area of special flood hazardSpecial Flood
Hazard Areas, regulatory floodplain, the elevation of the base flood, pre- and post-development water
surface elevations, and pre- and post-development floodplain limits;
3. All tentative, preliminary, and final subdivision plans will provide the elevation(s) of proposed
structure(s) and pads. If the site is filled above the base flood elevation, the final lowest floor and pad
elevation shall be certified by an Arizona registered professional civil engineer or an Arizona registered
professional land surveyor and provided to the Floodplain Administrator and the Town Building Official;
4. Final and preliminary plats shall show the limits of the regulatory floodplain and the regulatory
floodway;
5. Tentative and preliminary plats and plans (also referred to as a final site plan) shall show proposed
improvements for areas subject to flooding and/or for areas which contain extremely poor drainage
facilities such that the proposed improvements make the areas safe from flooding for the respective type
of occupancy.
F. Street Elevations.
1. Refer to the Town’s adopted Drainage Criteria Manual and subdivision street standards for additional
information and requirements.
2. Fill used for the streets in areas subject to flooding shall not increase flood heights more than a
designated amount as defined in Section 17-5-8(A)(1)(b).
3. The developer shall provide pre- and post-developed water surface elevation for streets proposed for
placement in or adjacent to areas subject to flooding. Headwater ponding limits and water surface
elevations shall be shown upstream of all culvert crossings.
G. Building Site.
1. Residential lots shall contain a building site, either natural or manmade, which is not subject to
flooding by the base flood.
2. In areas subject to flooding by the base flood, where no fill is proposed, the building line shall be
located no closer to the watercourse or channel than the edge of the area subject to flooding by the base
flood. In areas where fill is used to raise the elevation of the building site, no fill shall be placed in the
regulatory floodway, and the building line shall be located no less than twenty-five (25) feet landward
from the edge of the fill.
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H. Setback from Channels. Along reaches of all regulated watercourses, erosion hazard setback requirements
from banks of washes shall be established in accordance with the Town’s adopted Drainage Criteria Manual or
standards accepted by the Town Engineer.
I. Easements for Drainage. Whenever any watercourse is located in the area being subdivided, an easement or
common area encompassing each side of the watercourse shall be provided for the purpose of protecting and/or
maintaining the watercourse for flood and drainage purposes, and such further width for construction of bank
protection or for allowing for natural meander of the stream or watercourse that may be reasonably expected,
or for all these as will be adequate for the purpose, as determined by the Town Engineer.
J. Detention/Retention Systems. See Town’s adopted Drainage Criteria Manual for requirements pertaining to
detention/retention systems by visiting the administrative offices of the Town of Oro Valley. ((O)17-04,
04/05/2017; (O)05-35, 10/05/2005)
17-5-5 Standards for Manufactured Homes.
All manufactured homes that are placed within or substantially improved while located within a regulatory
floodplain shall:
A. Be elevated so that the lowest structural member or the lowest point of any attached appliances, whichever
is lower, is at or above the regulatory flood elevation; and
B. Be securely anchored to an adequately anchored foundation system to resist flotation, collapse, or lateral
movement. This anchoring requirement is in addition to applicable State and local anchoring requirements for
resisting wind forces.
C. Upon completion of installation of the manufactured home, certification by a registered professional
engineer or surveyor that the elevation requirements of this section have been satisfied shall be provided to the
Floodplain Administrator for verification. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-5-6 Standards for Recreational Vehicles.
All recreational vehicles placed within a regulatory floodplain area will either:
A. Be on site for fewer than one hundred eighty (180) consecutive days, and be fully licensed and ready for
highway use, to the extent that they are not prohibited by any other ordinance. A recreational vehicle is ready
for highway use if it is on its wheels or jacking system, is attached to the site only by quick disconnect type
utilities and security devices, and has no permanently attached additions; or
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 31 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
B. Meet the permit requirements of Article 17-4, and the elevation and anchoring requirements for
manufactured homes in Section 17-5-5. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-5-7 Floodways.
Located within regulatory floodplain areas, established in Section 17-3-2, are areas designated as floodways.
Since the floodway is an extremely hazardous area due to the velocity of floodwaters that carry debris,
potential projectiles, and increase erosion potential, the following provisions apply:
A. Encroachments, including fill, new construction, substantial improvements, and other development are
prohibited in floodways. The Floodplain Administrator will consider encroachments where certification by an
Arizona registered professional civil engineer is provided demonstrating that encroachments will result in no
increase in flood levels during the occurrence of the base flood discharge, and that the encroachment will not
pose a threat to life or property.
B. Floodway Requirements.
1. Uses Permitted. The following open space uses shall be permitted within a floodway to the extent that
they are not prohibited by any other ordinance or State or Federal permit requirements, nor conflict with
uses permitted in adjoining zones, and provided they do not require structures, fill, or storage of materials
or equipment:
a. Agricultural uses, including general farming, pasture, grazing or outdoor plant nurseries,
horticulture, viticulture, truck farming, sod farming, wild crop harvesting, and restoration of native
vegetation;
b. Private and public recreational uses;
c. Accessory residential uses, including lawns, gardens, and play areas.
C. Limitations.
1. No use shall be allowed within a floodway which:
a. Acting alone or in combination with existing or future uses creates a danger or hazard to life or
property;
b. Increases the water surface elevation of the base flood; or
c. Adversely affects groundwater recharge.
2. No on-site waste disposal systems or septic drain fields shall be installed wholly or partly in a
floodway.
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 32 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
D. If Section 17-5-917-5-7 is satisfied, all new construction and substantial improvements shall comply with
all other applicable flood hazard reduction provisions in this article. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-5-8 Floodway Fringe Area Requirements.
A. Floodway fringe areas shall be subject to the following regulations:
1. The following uses shall be permitted within a floodway fringe area to the extent that they are not
prohibited by any other ordinance but only upon issuance of a Floodplain Use Permit:
a. Any use permitted in Section 17-5-7.
b. Any other use not involving structures, provided it is elevated above the regulatory base flood
elevation and a determination is made by the Town Engineer that the use will not increase the base
flood elevation more than one (1) foot where the owner of the land doing the development owns both
sides of the floodway, and not more than one-tenth (0.1) foot where only one (1) side is owned. In no
case shall the development increase the water surface elevation more than one-tenth (0.1) foot on the
property owned by others upstream and downstream, nor unduly restrict the capacity of the channels
or floodway of tributaries to the main stream or watercourse, drainage ditches, or other drainage
facilities or systems. The aforementioned water surface elevation increases apply to all watercourse
channels in Oro Valley except the Canada del Oro Wash where the elevation of the existing levee
system and bank protection will allow for no water surface elevation increases due to encroachment.
Additionally, when main channel flood-flow velocities are greater than four (4) feet per second (fps),
a land use/development activity shall not increase flood-flow velocities immediately downstream of
the activity by more than one (1) fps or ten percent (10%), whichever is less, in the regulatory
floodway. Any velocity increase greater than the aforementioned criteria must be reviewed and
approved by the Town Engineer.
c. Structures, including dwellings, may be erected or moved, provided the lowest floor or basement
floor is placed at or above the regulatory flood elevation. Land may be filled, provided that the top of
such fill shall be at or above the regulatory flood elevation for the particular area, and shall extend at
such elevations at least twenty-five (25) feet beyond the limits of any structure erected or placed
thereon. The placement of structures and any accompanying fill shall not affect base flood elevation
beyond the limits set in subsection (A)(1)(b) of this section.
B. The following minimum requirements apply in all zones designated on the FIRM, and the floodplain of
those watercourses with a base flood flow rate equal to or greater than fifty (50)one hundred (100) cfs:
1. All new construction (including prefabricated structures and mobile homes) and substantial
improvements shall be anchored to prevent flotation and lateral movement, and be constructed with flood
resistant materials and methods.
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 33 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
2. All proposed plats and proposals for other developments, including their utilities, streets, and drainage
structures, shall be located and designed to be consistent with the need to minimize flood damage.
3. All tentative development plans, site plans, final site plans, improvement plans, and final plats, and
other proposed new developments shall include base flood elevation data or as otherwise directed by the
Town Engineer.
4. The Town must be furnished, for permanent record, all elevations and flood-proofing levels for all
new or substantially improved structures, whether such structures contain a basement.
5. If in a riverine situation, all adjacent communities and the State Coordinating Office must be notified
prior to any alteration or relocation of the watercourse, and copies of such notifications must be sent to the
FEMA. Within the proposed altered or relocated portion of any watercourse, the flood carrying capacity
shall be maintained.
6. Within one hundred twenty (120) days after completion of construction of any flood control protective
works which changes the rate of flow during the flood, or changes the configuration of the floodplain, the
person or agency responsible for installation of the protective works shall provide to the governing bodies
of all jurisdictions affected by the protective works a new delineation of all floodplains affected. The new
floodplain delineation shall be done according to the criteria adopted by the State of Arizona Director of
Water Resources.
C. Limitations.
1. No use shall be allowed within a floodway fringe which:
a. Acting alone or in combination with existing or future uses creates danger or hazard to life or
property.
b. Increases the water surface elevation for the base flood by more than that allowed under
subsection (A)(1)(b) of this section;
c. Adversely affects groundwater recharge.
D. Critical Facilities.
1. Critical facility means any of the following:
a. A structure or facility that produces, uses or stores highly volatile, flammable, explosive, toxic,
and/or water reactive materials;
b. Hospitals, emergency medical facilities, nursing homes and/or housing facilities likely to have
occupants who may not be sufficiently mobile to avoid injury or death during a flood;
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 34 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
c. Essential emergency response facilities, such as police stations, fire stations, emergency shelters
and/or operation centers that are needed for public safety and/or flood response activities before,
during and after a flood; and
d. Public and private utility facilities, such as but not limited to power, water and wastewater
treatment, and/or communications, that are vital to maintaining or restoring normal services to
flooded areas before, during and after a flood.
2. Applicability. The critical facility requirements shall only apply along watercourses which have
FEMA designated floodplains. Where the two-tenths percent (0.2%) chance floodplain has not been
established, the Town Engineer may require that this floodplain be delineated by the applicant.
3. Critical facilities shall be located outside of the two-tenths percent (0.2%) annual chance (five
hundred (500) year) floodplain, if possible. If a critical facility must be located in a two-tenths percent
(0.2%) annual chance (five hundred (500) year) floodplain, it must be demonstrated that there is either a
critical need to locate it within the floodplain, or that there is not a suitable alternative site, as justified by
an Arizona registered civil engineer. Any critical facility located within a two-tenths percent (0.2%)
annual chance (five hundred (500) year) floodplain shall be protected from that event. Protection includes,
but is not limited to, elevating the lowest floor and all utilities and mechanical services to a minimum of
one (1) foot above the base flood or to the two-tenths percent (0.2%) annual chance (five hundred (500)
year) floodplain water surface elevation, whichever is greater, providing elevated access ramps, if
appropriate, adequately protecting the facility from both lateral and vertical erosion associated with the
two-tenths percent (0.2%) annual chance (five hundred (500) year) floodplain, providing all weather
access during the base flood and developing an emergency response plan.
4. Existing critical facilities within the two-tenths percent (0.2%) annual chance (five hundred (500)
year) floodplain that propose substantial improvements and/or repairs shall be protected from the
two-tenths percent (0.2%) annual chance (five hundred (500) year) flood event. Protection includes, but is
not limited to, elevating or flood proofing the lowest floor and all utilities and mechanical services to a
minimum of one (1) foot above the base flood or to the two-tenths percent (0.2%) annual chance (five
hundred (500) year) floodplain water surface elevation, whichever is greater, providing elevated access
ramps, if appropriate, adequately protecting the facility from both lateral and vertical erosion associated
with the two-tenths percent (0.2%) annual chance (five hundred (500) year) floodplain, providing all
weather access to the base flood and developing an emergency response plan. ((O)17-04, 04/05/2017;
(O)05-35, 10/05/2005)
17-5-9 Flood Related Erosion-Prone Area.
The protection of Town residents and their property from injury and damage that can occur as a result of
streambank lateral migration due to erosion and scour is of primary importance in the administration of this
chapter and the following criteria apply:
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 35 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
A. The Floodplain Administrator shall require Floodplain Use Permits for proposed construction and other
development within all flood related erosion-prone areas, as determined by lateral migration analysis described
in the Town’s Drainage Criteria Manual or in other predetermined, documented evidence. Areas generally
most susceptible to lateral erosion and scour include, but are not limited to, locations of historical stream/wash
meandering, locations where poorly defined or poorly consolidated banks occur, wash reaches characterized by
changes in the direction, velocity, or amount of streamflow, and locations in the proximity of stabilizing
features or structures such as rock outcrops or bridges.
B. Permit applications shall be reviewed to determine whether the proposed site alterations and improvements
will be reasonably safe from flood-related erosion, and will not cause flood-related erosion hazards or
otherwise aggravate the existing hazard.
C. If a proposed development or structure including associated permanent features such as a patio wall or
swimming pool or any other feature is found to be in the path of flood-related erosion, or would increase the
erosion hazard, such improvements shall be relocated or adequate protective measures shall be taken to avoid
aggravating the existing erosion hazard.
D. Adjacent to all washes with a base flood flow rate of fifty (50) cfs or more, a setback from the wash is
required for all new development to create a safety buffer. The setback shall be determined using the method
outlined in the Town of Oro Valley Drainage Criteria Manual. The buffer may be used for suitable open space
purposes, such as for outdoor recreation and wildlife habitat areas, and for other activities using temporary and
portable structures only. The erosion setback shall be calculated streamward from the outermost
permanent/fixed feature on the property and this structure or feature constructed in such a manner that it will
be protected should lateral channel migration occur to its base. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
Article 17-6
APPEAL AND VARIANCE PROCEDURES
Sections:
17-6-1 Nature of Variances
17-6-2 Floodplain Board
17-6-3 Appeals and Request for Variance Considerations
17-6-4 Conditions for Variances
17-6-1 Nature of Variances.
The variance criteria set forth in this article are based on the general principle of zoning law that variances
pertain to a piece of property and are not personal in nature. A variance may be granted for a parcel of property
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 36 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
with physical characteristics so unusual that complying with the requirements of this chapter would create an
exceptional hardship to the applicant or the surrounding property owners. The characteristics must be unique to
the property and not be shared by adjacent parcels. The unique characteristic must pertain to the land itself, not
to the structure, its inhabitants, or the property owners.
It is the duty of the Town of Oro Valley to help protect its citizens from flooding. This need is so compelling
and the implications of the cost of insuring a structure built below the base flood elevationRegulatory Flood
Elevation are so serious (as much as twenty-five dollars ($25.00) for one hundred dollars ($100.00) of
insurance coverage) that variances from the base flood elevationRegulatory Flood Elevation shall not be
granted. Variances from other requirements in the floodplain management ordinance are quite rare. The
long-term goal of preventing and reducing flood loss and damage can only be met if variances are strictly
limited. Therefore, the variance guidelines provided in this chapter are detailed and contain multiple provisions
that must be met before a variance can be properly granted. The criteria are designed to screen out those
situations in which alternatives other than a variance are more appropriate.
Additionally, ARS § 48-3609(J) states that the land for which the variance is granted shall be ineligible for
exchange of State land pursuant to the flood relocation and land exchange program provided for by Title 26,
Chapter 2, Article 2. A copy of the notice shall be recorded in the office of the Pima County Recorder and shall
be recorded in a manner so that it appears in the chain of title of the affected parcel of land. The Floodplain
Administrator shall maintain a record of all variance actions, including justification for their issuance, and
report such variances in a biennial report to FEMA and ADWR. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-6-2 Floodplain Board.
A. The Floodplain Board of Oro Valley shall hear and decide requests for variances from the requirements of
this chapter to FEMA regulated floodplains, as well as hear appeals to decisions from previous determinations
or actions on non-FEMA regulated floodplains by the Floodplain Administrator or the Town Engineer.
B. The Floodplain Board shall hear and decide appeals when it is alleged there is an error in any requirement,
decision, or determination made by the Floodplain Administrator in the enforcement or administration of this
chapter with regard to FEMA regulated floodplains and floodplains identified on the Town’s Flood Insurance
Rate Maps. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-6-3 Appeals and Request for Variance Considerations.
A. In passing uponconsidering appeals and requests for variance, the Floodplain Board shall consider all
technical evaluations, all relevant factors, and all standards specified in other sections of this chapter, and also
consider:
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 37 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
1. The danger that materials may be swept onto other lands to the injury of others;
2. The danger of life and property due to flooding or erosion damage;
3. The susceptibility of the proposed facility and its contents to flood damage, and the effect of such
damage on the individual owner;
4. The importance of the services provided by the proposed facility to the community;
5. The necessity to the facility of a waterfront location, where applicable;
6. The availability of alternative locations for the proposed use that are not subject to flooding or erosion
damage;
7. The compatibility of the proposed use with existing and anticipated development;
8. The relationship of the proposed use to the comprehensive plan and floodplain management program
for the area encompassing the proposed use;
9. The safety of access to the property in time of flood for ordinary and emergency vehicles;
10. The expected heights, velocity, duration, rate of rise, and sediment transport of the floodwaters
expected at the site; and
11. The costs of providing governmental services during and after flood conditions, including
maintenance and repair of public utilities and facilities such as sewer, gas, electrical, water system, and
streets and bridges.
B. Upon consideration of the factors of subsection (A) of this section and the purposes of this chapter, the
Floodplain Board may attach such conditions to the granting of appeals and variances as it deems necessary to
further the purposes of this chapter.
C. The Floodplain Administrator shall maintain a record of all variance actions, including justification for
their issuance and shall report any such variances that are issued in FEMA regulated floodplains in its biennial
report, which is also submitted to the Federal Emergency Management Agency.
D. Any applicant to whom a variance is granted shall be given written notice over the signature of the
Floodplain Administrator, or their designee, that:
1. The issuance of a variance to construct a structure below the base flood elevation will result in
increased premium rates for flood insurance up to amounts as high as twenty-five dollars ($25.00) for one
hundred dollars ($100.00) of insurance coverage; and
2. Such construction below the regulatory flood elevation increases risks to life and property; and
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 38 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
3. The land upon which the variance is granted shall be ineligible for exchange of State land pursuant to
the flood relocation and land exchange program provided by ARS § 37-610. A copy of the notice shall be
recorded in the office of the Pima County Recorder and shall be recorded in a manner so that it appears in
the chain of title of the affected parcel of land.
E. A person aggrieved in any manner by an action of the Floodplain Review Board may within thirty (30)
days appeal to the Floodplain Board. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
17-6-4 Conditions for Variances.
A. Variances shall only be issued upon:
1. A showing of good and sufficient cause;
2. A determination that the variance is the minimum necessary, considering the flood hazard, to afford
relief;
3. A determination that failure to grant the variance would result in exceptional hardship to the applicant;
4. A showing that the use cannot perform its intended purpose unless it is located or carried out in close
proximity to water. This includes only facilities defined in Article 17-2 in the definition of “functionally
dependent use” (which is unlikely due to the Town of Oro Valley’s arid climate); and
5. A determination that the granting of a variance will not result in increased flood heights, additional
threats to public safety, extraordinary public expense, create nuisances, cause fraud on or victimization of
the public, or conflict with existing local laws or ordinances.
B. Variances shall not be issued within any designated regulatory floodway if any increase in regulatory
floodway elevationBase Flood Elevation would result during the base floodBase Flood discharge.
C. Variances may be issued for the repair, rehabilitation, or restoration of structures listed in the National
Register of Historic Places or the State Inventory of Historic Places upon a determination that the proposed
repair or rehabilitation will not preclude the structure’s continued designation as a historic structure, and that
the variance is the minimum necessary in order to preserve the historic character and design of the structure.
D. The Floodplain Administrator, at his/her discretion, may grant a variance for non-FEMA regulated flood
hazard areas.
E. Generally, variances may be issued for new construction and substantial improvements to be erected on a
lot of one-half (0.5) acre or less in size contiguous to and surrounded by lots with existing structures
constructed below the regulatory flood elevation, provided the procedures of Articles 17-4 and 17-5 have been
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 39 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
fully considered. As the lot size increases beyond one-half (0.5) acre, the technical justification required for
issuing the variance increases. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
Article 17-7
ORDINANCE AMENDMENTS
Sections:
17-7-1 Procedures
17-7-1 Procedures.
A. The Floodplain Board may from time to time, after a public hearing required by law (ARS § 38-431.01,
and other open meeting laws), amend, supplement, or change the regulations set forth herein or subsequently
established. Any amendment, supplement, or change may be initiated by the Floodplain Board or by petition of
affected persons hereafter provided.
B. The procedures established by this article are to provide for appropriate and timely ordinance amendments,
with due consideration of the purpose of this article. ((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
Article 17-8
FEES
Sections:
17-8-1 Fee Schedule
17-8-1 Fee Schedule.
Fees for Floodplain Use Permits will be charged based on the fee schedule approved by the Town Council.
((O)17-04, 04/05/2017; (O)05-35, 10/05/2005)
Chapter 17 Floodplain and Erosion Hazard Management | Oro Valley Town Code Page 40 of 40
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
The Oro Valley Town Code is current through Ordinance (O)20-10, passed November 4, 2020.
Disclaimer: The Town Clerk’s Office has the official version of the Oro Valley Town Code. Users should
contact the Town Clerk’s Office for ordinances passed subsequent to the ordinance cited above.
Note: This site does not support Internet Explorer. To view this site, Code Publishing Company recommends
using one of the following browsers: Google Chrome, Firefox, or Safari.
Town Website: www.orovalleyaz.gov
Code Publishing Company
Stormwater Utility Commission 5.
Meeting Date:03/18/2021
Requested by: John Spiker, Public Works Submitted By:John Spiker, Public Works
SUBJECT:
REPORT AND DISCUSSION OF THE STORMWATER UTILITY'S CARTEGRAPH / GIS INTEGRATION
AND ASSET MANAGEMENT PROCEDURES
RECOMMENDATION:
N/A
EXECUTIVE SUMMARY:
As requested during the January 21, 2021, Stormwater Utility Commission Meeting, Stormwater Utility staff have
prepared a brief presentation demonstrating our current asset management and Stormwater Pollution Prevention
Plan (SWPPP) inspection program. More information is given below.
BACKGROUND OR DETAILED INFORMATION:
The Town of Oro Valley Stormwater Utility (SWU) has three important responsibilities, among others, related to (1)
Stormwater Quality, (2) Stormwater Quantity, and the (3) Operation and Maintenance of the Town's drainage
infrastructure. The overall goal of the water quality mission is to ensure that discharges from the Municipal Separate
Storm Sewer System (MS4) do not cause or contribute to exceedances of surface water quality standards set by
the Environmental Protection Agency (EPA) and enforced by Arizona Department of Environmental Quality
(ADEQ). Consequently, the Town must systematically implement, and report annually regarding six minimum
control measures (MCMs) as described in our Stormwater Management Program. The Town also has the
responsibility to enforce Federal and State floodplain management regulations regarding flood protection and
floodplain management, hence known as stormwater quantity. The primary goal of our water quantity mission is to
continue efforts during the building-permit-review process to minimize threat to life and property from flooding.
Additionally, the SWU is also responsible for regularly inspecting drainage infrastructure for operability and
structural integrity.
It is far easier for the SWU to fulfill these responsibilities when tasks are organized and tracked using a combination
of Cartegraph Operations Management Software (OMS), an asset and work management software, and ESRI
ArcGIS software, a geographic information system for working with maps and geographic information maintained by
the Environmental Systems Research Institute, both of which are linked to the Town's Geographic Information
System (GIS).
Our asset and SWPPP management process includes data collection, assess condition, gauge of performance, and
establishing a record of the inspection event and its recommendations.
With regard to data collection, to date, the SWU staff has captured 4853 assets within the Town. This represents
an estimated 80% of the stormwater assets, not including new assets put in place during new construction. The
SWU has a goal of inspecting a minimum of 20% of these assets each year, and all public and private drainage
assets being looked at within a 5-year period. Assets with known issues are placed into a reoccurring inspection
calendar for additional follow up depending on severity and type of maintenance problems encountered. Typical
drainage assets captured include: Catch Basins and Curb Inlets, Storm Drain Pipes, Drainage Channels, Culverts,
Detention Basins, and Channel Outfalls. In addition, spatial data related to residential and commercial construction
sites are also captured in our GIS spatial database, and SWPPP inspections are scheduled and recorded in
Cartegraph. Similarly, construction sites are also cataloged, and to date we have 80 subdivisions in our database,
with 17 active sites.
Attached is a set of examples of workflow for asset maintenance / repair as well as SWPPP inspection and
corrective action.
FISCAL IMPACT:
N/A
SUGGESTED MOTION:
For informational purposes only.
Attachments
Asset Presentation
INA ORACLELA CHOLLALA CANADAMOORE
TANGERINE
LAMBERT
MAGEESHANNON 1STNARANJA
OVERTON
WILDS
KINGAIRHARDY
CHRISTIENORTHERNLAGO DEL OROR
A
N
C
H
O
V
I
S
T
O
S
O
MONA LISAGOLDER RANCH
LIND A V ISTA
CALLE CONCORDI A TWIN LAKESS
K
Y
LIN
E
PUSCH VIEW
MAGEE LA CHOLLA1STTown of Oro ValleyPublic & Private Drainage Assets 2021
¯
Legend
1794 Catch Basins & Curb Inlets
1188 Storm Drain Pipes
1037 Drainage Channels
563 Culverts
225 Detention Basins
46 Public & Private Outfalls
Major Streets
Oro Valley Town Limits
Miles01.5 3
STORMWATER UTILITY
Stormwater Conveyance Asset Types
Detention
Basin at El
Corredor
Constructed
Channel at
the Villages
of La
Canada
Storm Drain
Pipe at El
Corredor
Culvert
under La
Canada
Municipal
Outfall Near
Pusch View
& The CDO
Catch Basin
on Lambert
Lane
STORMWATER UTILITY
Storm Inlet Cartegraph ID 428
STORMWATER UTILITY
Storm Inlet Cartegraph ID 428 Inspection 3/19/2018
STORMWATER UTILITY
Storm Inlet Cartegraph ID 428 Inspection Task 3/19/2018
STORMWATER UTILITY
Storm Inlet Cartegraph ID 428 Inspection Report 3/19/2018
STORMWATER UTILITY
Storm Inlet Cartegraph ID 428 Request For Repair 3/20/2018
STORMWATER UTILITY
Storm Inlet Cartegraph ID 428 Repair Task 4/24/2018
STORMWATER UTILITY
Storm Inlet Cartegraph ID 428 Post-Repair Inspection Task 10/17/2019
STORMWATER UTILITY
Storm Inlet Cartegraph ID 428 Post-Repair Inspection Report 10/17/2019
STORMWATER UTILITY
Storm Inlet Cartegraph ID 428 Current Status
Moore Road Extension November, 2020(Drone Flight)
¯Feet05001,000
Legend
Moore Road Extension
9 New Culverts
6 New Drainage Channels
8 New Storm Drain Pipes
19 New Catch Basins & Curb Inlets
INA ORACLELA CHOLLALA CANADAMOORE
TANGERINE
LAMBERT
MAGEESHANNON 1STNARANJA
OVERTON
WILDS
KINGAIRHARDY
CHRISTIENORTHERNLAGO DEL OROR
A
N
C
H
O
V
I
S
T
O
S
O
MONA LISAGOLDER RANCH
LIND A V ISTA
CALLE CONCORDI A TWIN LAKESS
K
Y
LIN
E
PUSCH VIEW
MAGEE LA CHOLLA1STLa Canada Ridge SubdivisionCartegraph/GIS ID (SWPPP 6)
¯
Legend
Major Streets
La Canada Ridge (SWPPP 6)
Oro Valley Subdivisions
Oro Valley Town Limits
Miles01.5 3
La Canada Ridge
STORMWATER UTILITY
Cartegraph/GIS ID (SWPPP 6) Pre-Correction Inspection Report
STORMWATER UTILITY
Cartegraph/GIS ID (SWPPP 6) Pre-Correction Inspection Report
STORMWATER UTILITY
Cartegraph/GIS ID (SWPPP 6) Post-Correction Inspection Report
STORMWATER UTILITY
Cartegraph/GIS ID (SWPPP 6) Post-Correction Inspection Report
Stormwater Utility Commission 6.
Meeting Date:03/18/2021
Requested by: John Spiker, Public Works Submitted By:John Spiker, Public Works
SUBJECT:
DISCUSSION OF 2021 STORMWATER UTILITY COMMISSION FIELD TRIP DELIVERY ALTERNATIVES
RECOMMENDATION:
N/A
EXECUTIVE SUMMARY:
Due to COVID 19 restrictions the field trip was canceled in 2020. Due to the ongoing pandemic, the restrictions
remain in place for limited in-person meetings with no identifiable timeframe to be lifted. The pandemic and
associated restrictions remain a hurdle to providing the commissioners the ability to meet in-person for a tour of
stormwater assets and issues.
Stormwater Utility staff would like to discuss options and entertain ideas from the Commissioners as to avenues to
deliver a 2021 field trip experience.
BACKGROUND OR DETAILED INFORMATION:
The goal of the field trip is to visit places in Oro Valley that will give the Commissioners a better understanding
of the broad range of activities typically performed by the Stormwater Utility. Possible sites to be visited may
include places where the following activities occur.
•Public Drainage Infrastructure Inspection (MS4), Maintenance & Repair
•Private Drainage Infrastructure Inspection, Maintenance & Repair
•SWPPP Inspections (current construction projects)
•SWPPP Inspections (verification of post-construction control measures)
•Illicit Discharge Detection and Elimination (IDDE): Enforcement Action
•Drainage Complaints: Evaluation and Response
•Capital Improvement Projects: Selection, Design and Construction Oversight
•Coordination with Pima Co. Regional Flood Control District: LOMR’s, Studies, and Watercourse Maintenance
•Verification of Municipal Operation’s Good-Housekeeping Practices
The time, date, and locations to be visited are to be determined by staff and issued for public notification. No official
Town business will be conducted at this function.
FISCAL IMPACT:
N/A
SUGGESTED MOTION:
N/A
Stormwater Utility Commission 7.
Meeting Date:03/18/2021
Requested by: John Spiker, Public Works Submitted By:John Spiker, Public Works
SUBJECT:
DISCUSSION AND POSSIBLE ACTION REGARDING THE CANCELLATION OF THE APRIL 15,
2021 SWUC REGULAR SESSION MEETING
RECOMMENDATION:
N/A
EXECUTIVE SUMMARY:
N/A
BACKGROUND OR DETAILED INFORMATION:
N/A
FISCAL IMPACT:
N/A
SUGGESTED MOTION:
I Move to approve (or deny) cancellation of the April 15, 2021 SWUC Regular Session Meeting