HomeMy WebLinkAboutMinutes - Environmentally Sensitive Lands Task Force - 3/25/2010 'R tr4
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Agenda
Environmentally Sensitive Lands (ESL)
Public Advisory Committee (PAC)
Thursday, March 25, 2010
4 p.m.
Hopi Conference Room
Development Services Building
11000 N. La Canada Dr.
1. Call to Order
2. Schedule
• ESL Steps Remaining: View sheds (Oracle, Tangerine, Other Arterials
Identified in the General Plan, and Parks), Final ESL Map Review,
Mitigation Standards, Cultural, and Administration
• Planning & Zoning Commission Public Hearing and Town Council
Meeting in May
3. Section D. Design Requirements
• Site Tour Discussion
• Compact Development
• Updates to "Permitted Uses" and "Flexible Development Standards"
4. Section G. Hillside Regulations
• Existing Oro Valley Zoning Code
• Proposed Section G. Hillside Regulations
5. Adjourn
Posted: 03 24 10 10:00 a.m. cp
The Town of Oro Valley complies with Americans with Disabilities Act (ADA). If
any person with a disability needs any type of accommodation, please notify the
Clerk's office at 229-4700.
"Notice of Possible Quorum of the Oro Valley Town Council: In accordance
with Arizona Open Meeting Law A.R.S. X38-431 et seq, a majority of the Town
Council may attend the above referenced meeting as a member of the audience
only."
�ALt�Y App
DRAFT MEETING SUMMARY
Town of Oro Valley
ENVIRONMENTALLY SENSITIVE LANDS (ESL)
iPUBLIC ADVISORY COMMITTEE MEETING #21
'VJIs';F„eva"'e4 0}F tiAx
, TALLY
POUNDED 01�
March 25, 2010
4-6p
HOPI CONFERENCE ROOM
11000 N. LA CANADA DR.
PAC Members Present:
Bill Adler
Susan Simms
Doug McKee
Steve Solomon
Philip Kline
Don Chatfield (by phone)
Steve Ta i l l ie
Oro Valley ESL Team Members Present:
David Williams
Bayer Vella
Joe Andrews
Arinda Asper
1. Call to Order - Meeting called to order at 4:06 p.m.
2. Schedule
Bayer Vella discussed the following:
• ESL Steps Remaining: View sheds, Final ESL Map Review, Mitigation
Standards, Cultural, and Administration
• P&Z Commission Public Hearing and Town Council Meeting in May
• Final ESL map review is expected soon.
• There has been a strong request for the ESL matter to be put on a Town
Council agenda soon. Staff believes additional time is needed, as the PAC
is having substantive discussions. The PAC will likely keep working through
June, then shut down for 3 weeks for staff to update the entire document, and
return in July to meet the target completion date in August.
• Suggestion that agreement is reached by all PAC members before returning
to a past discussion. The PAC needs to move forward and get this right, and
only go back to an issue if new information needs to be discussed.
Bill Adler, Steve Solomon and Doug McKee expressed concern about the
pressure to complete. Don Chatfield said he agreed but also believes the PAC
has spent too much time on unnecessary issues and he would appreciate a
F:\SR OFFICE SPEC\Projects for COMMUNICATIONS\ESL\ESL PAC\ESL PAC 15 3-25- 1
10 meeting summary.doc
timeframe. David Williams said we do not want to squelch discussion, but we
don't want to continue returning to past discussions needlessly.
Two PAC members commented that since detailed notes are no longer being
taken and no voting occurs, they don't always recall what was discussed or
decided. It was agreed that the meeting process and decision-making.needs to
be formalized. If anyone has concerns or questions, they are to be
communicated to Mr. Vella. One member said that a vote might help with the
issue that some members don't contribute as much.
The PAC will get each chapter back with comments. The PAC will use the
acknowledgement process through the review of each chapter, and then we will
have a show of hands on approval of any changes. At end of he process, we
want to have the entire group on the same page as much as possible, ensuring
that all issues have been discussed, that everyone has been heard and that
there is no dissention. Everyone agreed that was a fair method of process.
3. Section D. Design Requirements
• Site Tour and Compact Development Discussion
Bayer Vella: Discussion of Compact Development is what prompted the site
tour. The value of seeing Milagro is that it's an alternative way to develop a
co-housing subdivision. Built five years ago, Milagro consists of a 42-acre
parcel, with only 2 acres developed with 3,000 square foot lots, and strongly
makes the case that cluster developments can be successful. Prices range
from $400K to $500K.
Steve Solomon cautioned against making general statements that cluster
building will automatically bring high prices, and suggested that this option be
offered with possibly some development incentives. Don Chatfield said that
it is not the intent that all development be of that high density, but when it is
done right it doesn't have to create ghetto hysteria. This is one of things that
we can offer, but not necessarily require. Key issue is that this might help us
create a menu of available offerings. Susan Simms agreed.
• Updates to "Permitted Uses" and "Flexible Development Standards"
David Williams drew a table offering the options given to developers
Tier ESOS Lot
25% 40% preservation
II 66% 80%
III Min. Met +10%
IV +10% +20%
Tiers I & II do not require rezoning; Tiers III & IV would require rezoning.
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s t
The following topics were discussed:
• Various options that could be offered to developers interested in
cluster developments
• ESL would be used by developers who will be rezoning; the other
option is developing per existing restrictions.
• Lot size option, as set out in Table 111-4, page 7 of Section D.
Table sets the boundaries of where the developer can work from.
Milagro's smallest homes with a garage are 5,500 square feet.
• Bill Adler: Problem with this section of the ordinance is that we are
being too proscriptive instead of letting demand give us the answer.
Don't believe it's up to us to suggest or demand a specific density.
• Steve Solomon: We are just setting a minimum lot size; it would be
up to the developer to decide.
• Everyone except Doug McKee agreed to allow a developer the
choice of developing a Milagro. Mr. McKee's reasoning is due to
separated parking that would be needed if lots were less than 5000.
• No one objected to offering developers the flexibility of reducing lot
sizes. Right now, in OV the minimum lot size is 5,000 square feet.
• Doug McKee cautioned that adjoining developments might not
accept a Milagro.
• Don Chatfield: Comfortable with lots in the range of 3000 to 5000
square feet.
• Lots with less than 5000 square feet would not include a garage.
• The PAC voted on the decision to allow developers the choice
of developing smaller lot sizes by lowering the size standard
to 3000 square feet. Steve Solomon, Bill Adler, Philip Kline,
Don Chatfield, Susan Simms and Steve Taillie all agreed to
allow for the development of 3000 square feet lots. Doug
McKee objected to the reduction of lot sizes, and he based his
option on the fact that smaller lot sizes would necessitate
separated parking, and also on his concern that adjoining
developments may not accept this type of development.
• Bill Adler asked if we were comfortable with site delivered housing.
David Williams said there is one in Oro Valley— Highlands MHP.
• Bayer Vella said that the second part of the issue is that most
codes require that a development be subject to a certain threshold
before a developer can take advantage of these incentives.
o Bayer Vella: Should you be able to use these Open Space
incentives? Should a threshold be set to trigger ESL
incentives for land that is not environmentally sensitive?
Currently, there is a 25% open space restriction; we need
direction.
o Doug McKee questioned why a threshold was needed at all,
and stated that he would prefer no threshold.
F:\SR OFFICE SPEC\Projects for COMMUNICATIONS\ESL\ESL PAC\ESL PAC 15 3-25- 3
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a 0
o Joe Andrews said that if we rezone at first, and it becomes
part of the code, the incentives are available to all. He
offered ideas on how we could get there under a no rezoning
approach.
o David Williams asked if could agree on 25% today.
o Bill Adler said he didn't know why we are asking for a
threshold, when it's the look of a project that matters, and
that's up to the residential and commercial code. Our
concern is in protecting that land. He doesn't think a
threshold is required.
o Don Chatfield asked how it would get implemented without
any threshold, and why the group was discussing applying it
to non-ESL lands. He would prefer the 25% flexible
approach.
o Philip Kline said there seems to be a reason for the
threshold.
o Steve Taillie said he would go with the majority vote. If
allowed under any situation, there is no incentive to the
developer who has ESL issues on the land, and would
therefore go with the 25%.
o Steve Solomon and Susan Simms said they were
comfortable with the 25% threshold.
o Bayer Vella said that the standard threshold is 40%.
• The PAC voted on the need for a threshold. Don Chatfield,
Steve Solomon, Susan Simms and Steve Taillie said they were
comfortable with the 25% threshold. Bill Adler said he didn't
think a threshold was required. Philip Klein said there seems
to be a reason for the threshold. Doug McKee voted no
threshold; he said he was inclined to encourage it if it had
some teeth on how it is used.
4. Section G. Hillside Regulations
To be discussed at future meeting.
5. Adjourn
Meeting adjourned at 6:07 p.m.
Prepared by:
Arinda Asper
Senior Office Specialist
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I s
DRAFT 3/12/10
Section D Table of Contents
1. Use Restrictions
2. Design Incentives
3. Design Standards
D. Use and Development Standards
1. ESOS Use Restrictions
A. Applicability
Areas reserved as ESOS upon completion of a rezoning are subject to
use restrictions and standards. Each must be recorded when land is
reserved by ESOS zoning,easement, and/or deed restriction.
B. Permitted Uses
1 Natural Open Space,
2 Trails,
3 Identification, use restriction, and/or interpretive signage,
4 Wildlife friendly protective fencing or walls subject to Planning and
Zoning Administrator review and approval,
5 Cultural Resource Exhibition,
6 Essential services as provided for in Section 3.D.1.d, Open Space
Requirements,
7 Within the Multiple Use Management Category,the following uses
are permitted subject to the criteria listed below and,Town - Deleted:Golf Courses within the
.. .. ... ...... .. ... .. ... ... ..
Council approval: Multiple Use Management Category
meeting the criteria listed below and
i. Golf Courses when: 4 subject to
1. Natural drainage patterns are maintained, and --- ---_-_ _. -___-.- _ -
2. Golf course best environmental management Formatted
practices for irrigation,fertilizer use and pest [Formatted
control are required.
ii. Passive and active recreation facilities that are
compatible with the conservation purposes of ESOS Formatted:Font:(Default)Arial, 11
and do not include impermeable surfaces. Allowable pt
facilities include but are not limited to: . Formatted:Font:(Default)Arial, 11
1. Soccer or ball field, •
pt
2. Volleyball court, Formatted:Font:(Default)Arial, 11
pt
. H.orseshoe pit,
4. P`ar course, , Formatted:Font:(Default)Arial,11
pt
5. Turf area. ;--
.. .. .. . .. .. ... .. .. .... .. ... .. ..
6. Benches, Formatted:Font:(Default)Arial, 11
pt
Draft 3.12.10 1 :aP�E:3Fi31":"A!3.Y
'tt 4r'. i!i�:.��:i
s
7. Picnic tables, Formatted:Font:(Default)Arial, 11 ,
8. Shade structures, ,pt
9. Barbecue grills, and - Formatted:Font:(Default)Arial, 11
10.Pathways. - pt
Formatted:Font:(Default)Arial, 11
C. Prohibited Uses pt
Formatted:Font:(Default)Arial, 11
1. Structures ,pt
2. Waste Disposal
3. Motorized vehicle access. `
except for ma.intenance. _. -�- Deleted:,
4. Recreational activities not contained within the confines of a
designated trail.
5. Off leash domestic animals
6. Establishment of non-native species
7. Removal of native vegetation unless approved for flood control
purposes by the Planning and Zoning Administrator.
D. Use Standards
1. Trails
Trails and associated amenities such as benches must conform to
standards established by the Oro Valley Parks and Recreation
Department.
2. Signs
a. Permanent signs shall be posted in ESOS areas indicating
the use restrictions contained in this Section.
b. Signs must conform to standards established by the Oro
Valley Parks and Recreation Department.
2. Development Balance and Incentives
A. Purpose
Achieving or exceeding base zoning densities and implementation of
conservation objectives are both supported. This section includes more
flexibility for site planning, lot sizes and dwelling types than permitted
under conventional, base zoning districts. Limited density increases may
be approved, Deleted: if additional open space is
provided beyond required minimums.
B. Applicability
The following design options may be applied to property or portions of
property reserved as ESL.
....... .............. .
1. When ESOS is applied to 25%or more of a project site,the
remaining areas are eligible to utilize the design options included
in this Section.
Draft 3.12.10 2 rs;.e:r:'g,:>vY2s.j.r
�s.¢,rots:��r:s
1
2. When ESOP,is applied to 66%or more of a project site, broader (Deleted:L open space J
flexibility is provided through,additional lot size reductions as ed:the remaining areas are
provided in Section D2,D3 d. eligible to utilize the design options
included in this Section,and
C. Flexible Development Standards
1. Process. Development standards may be modified to allow
flexibility by Town Council as a part of the rezoning process.
2. Review Criteria. The determination to permit a modification is
subject to the following findings:
a. Open space conservation is assured and there is a
measurable reduction in development area as a direct
result of the modification.
b. Enables development to the base zoning density, at a
minimum,for the entire site.
c. Compatibility with adjacent land uses is achieved through
architectural design,transition of density, buffers, and
placement of structures and improvements to reduce view
impacts.
d. Statutes,development agreements, appeal processes, or
other provisions of this code are not violated.
3. Standards Subject to Modification
The following standards may be modified as they relate to the
proposed construction of single family attached and detached
residences, multi-family residences,commercial, employment and
mixed use projects; - Formatted:Font:Not Bold
a. Building Setback and Landscape Bufferyard. Minimum
required distances may be reduced up to 20 percent
subject to the following limitations:
i. Side yards shall not be less than five feet, unless
a zero lot line design is utilized,
ii. Setback reductions shall not result in on-lot
driveway lengths that are less than 20 feet.
b. Minimum Lot Size. Minimum lot sizes in all R1, R-4, R-S
and SDH-6 districts may be modified subject to Cluster
Design requirements in Section D.
c. Off-Street Parking. Modifications resulting in reduced
amounts of parking and circulation area are supported.
Off-street parking requirements may be reduced in
accordance with Section 27.7.C.
Draft 3.12.10 3 1xi�E1tJFEbftAEEtE.l.Y
d. Building Height. Building heights for single family
attached and multi-family dwelling types may be increased
by no more than 1 ,feet and one additional story, -(Deleted:2
• Formatted:Font:Bold
e. Open Space. Open space requirements may be reduced
in accordance with Section III.C.3,Open S ace Formatted:List Paragraph, No
p bullets or numbering
Requirements.
•. (Formatted:Font:Bold
f. Mixed Use. Residential uses that are functionally Formatted:List Paragraph, No
bullets or numbering
integrated, including access, non-vehicular circulation, and
amenities,with commercial or employment uses may be
approved within commercial zoning districts.
EEditors note:A mixed-use zoning district must be -- Formatted:Indent:Left: 2.5"
developed, __�..... _. ..._ _�
-I Formatted:Font:Not Bold,Italic j
g. Modified Review Process. Development plans and Formatted:Font:Italic
preliminary plats submitted in conformance with the Formatted:List Paragraph, No
approved Tentative Development Plan, as determined by bullets or numbering
the Planning and Zoning Administrator, may be
administratively approved., (Formatted:Font:Bold
` Formatted:List Paragraph, No
h. Recreation Area Credit. Permissible passive and/or bullets or numbering
active recreational amenities located within Multiple Use
Management ESOS areas may be credited toward
residential recreation area requirements as approved by
the Planning and Zoning Administrator. (Formatted:Font:Bold
Formatted:List Paragraph, No
i. Native Vegetation Preservation. When 66%or more of a bullets or numbering
� J
site is preserved as Multiple Use Management ESOS,
requirements for native plant salvage,preservation and
restoration may be waived. This modification shall not
apply to areas of distinct vegetation which are designated
as a Core Resource by the ESL.
D. Cluster Design
1. Purpose
Cluster design concentrates residential development on a portion
of the available land in order to maximize protected open space,
improve the efficiency of infrastructure systems and offset the
reduction in development yield. Cluster options include potential
increases to development density.
2. General Requirements
a. Development shall be arranged in a manner to preserve
identified resources.
(Insert graphic)
Draft 3.12.10 4
b. The area to be developed must be consolidated to a
greater extent than permitted in Section 23.4 and provide a
concomitant increase in ESOS.
Insert Graphic: Traditional layout vs Cluster
c. The length of residential streets,driveways and utility lines
shall be reduced in comparison to a design that complies
with zoning standards identified in Section 23.4. The
length of collector streets shall not be considered in
assessing overall roadway reductions. (add graphic).
(Insert graphic)
d. Compatibility with adjacent land uses through architectural
design,transition of density, buffers, and placement of
structures and improvements must be achieved as follows:
i. Architectural Design. Structures shall include
architectural design features and a color palette
that is compatible with an adjacent subdivision(s).
Design compatibility is subject to Development
Review Board review and approval.
ii. Transition of Density. In perimeter areas
adjacent to residential development, a density
transition shall be provided utilizing base zoning
lot sizes. Reduced lot sizes shall not be placed
within 150 feet of adjacent residential uses or
ESOS areas.
(Insert graphic)
iii. Placement of Structures—cluster development
lots immediately abutting a residential subdivision
zoned R1-144, R1-43,or R1-36 shall meet base
zoning minimum lot size requirements.
(Insert graphic)
e. Cluster designs may employ any dwelling unit type
permitted by OVZCR, except site-delivered housing as
defined in Chapter 31. The following requirements apply;_ _ - Formatted:Font:Bold
- -�Formatted:Indent:Left: 2.5"
0174
Draft 3.12.10 5 mHt:3NtlAFr4L,'.f
i. Building heights must comply with base zoning, or - ---Formatted:Numbered+Level: 1+
building heights modified by an ESL rezoning Numbering Style:i,ii,iii,...+Start l
approval. at: 1+Alignment:Right+Aligned
at: 2.75"+Tab after: 3"+Indent
at: 3"
ii. Alternative dwelling unit types shall employ the
Formatted:Indent:Left: 2.5" j
OVZCR development standards associated with -=
an alternative dwellingtype. 'Formatted:Numbered+Level: 1+ 1
Numbering Style:i,ii,iii,...+Start
at: 1+Alignment:Right+Aligned
a) Townhouse dwellings are subject to R-4 ♦. at: 2.75"+Tab after: 3"+Indent
zoning standards in Section 23.7.A. at: 3"
4.•
(Formatted:_Indent:Left: 2.5" j
b) Multi-family dwellings are subject to R-6 ♦.• I Formatted:Numbered+Level:2+
zoning standards in Section 23.7.D. Numbering Style:a,b,c,...+Start
}at:1+Alignment:Left+Aligned at:
f. The sum total of square feet bywhich •. • ;3.25"+Tab after: 3.5"+Indent at: •
q t h eareaofeachlot , ; 3.5"
in the subdivision is reduced shall not exceed the total ,(Formatted:Indent:Left: 2.5"
square footage of the preserved area. ----_ -- -=-==-----=—
1 Formatted:Numbered+Level:2+
Numbering Style:a,b,c,...+Start
(Insert graphic) at: 1+Alignment:Left+Aligned at:
3.25"+Tab after: 3.5"+Indent at:
g. Any proposed increase in cluster density must be specified ,3.5
on the tentative development plan required for rezoning.
3. Compact Development
a. Compact development without an increase in density may
occur by reducing minimum lot sizes while retaining the
overall base zoning density as defined in Chapter 31.
Definition: Base Zoning Density: An expression of
residential land use density calculated by dividing the area
of the site or parcel, before any required dedications for
right-of-way or drainage, or designations for open space or
other OVZCR requirements, by the base zoning minimum
lot size. (See formula below)
(Note:As described above, base zoning density is
calculated using the'raw'or`gross' acreage of the site,
prior to any area deductions for infrastructure or other
uses. All density calculations are intended to be
completed in this manner.)
b. Residential lots may be reduced in size by 40 percent, but
shall not be smaller than the minimum lot areas set forth In
Table III-4.
c. When ESOS is applied to 66 percent or more of a project
site, residential lot size may be reduced by up to 80
percent, but in no case be less than 5,500 square feet.
Draft 3.12.10 6 f .=►,3avt.,.r
......•.tit:.lfJi:l
Table I11-4
Allowable Lot Size Reductions
District Minimum Base Zoning Lot Area Minimum Cluster Lot Size
R1-144 144,000 86,400
R1-43 43,000 24,000
R1-36 36,000 21,600
R1-20 20,000 12,000
R1-10 10,000 6,000
R1-7 7,000 5,500
SDH-6 6,000 5,500
•
4. Compact Development With Density Increase
a. When compact development designs are utilized and
minimum open space requirements of the ESLS are met, a
density increase of 10 percent above the base zoning
density is permitted. The additional density cannot result
in any reduction in required ESOS, [Formatted:Font:Bold
Formatted:Indent:Left: 2.5", No
b. A density incentive up to 20 percent of the base zoning bullets or numbering
density is permitted if ESOS requirements are exceeded
by 10 percent or more.
c. This density bonus provision may be applied when utilizing
the flexibility and modifications permitted in Section D.2.D,
Cluster Design.
d. The increase in density is calculated by multiplying the
area of additional ESOS times the density of the base
zoning district. Maximum density increases for
development are listed in Table 111-5.
Draft 3.12.10 +EItJiiASIIXelRi3.i
Formula to Calculate Density Bonus
Step One:
Base Zoning Density(expressed as dwellings per acre)=
,Site Area:Minimum Lot Area of Base Zone (Formatted:Font:Bold
Additional Dwellings Permitted=
Additional ESOS Area X Base Zoning Density (Formatted:Font:Bold
Step Two:
Allowable Density with Bonus= (Formatted:Left j
Additional Dwellings+ Base Zoning Dwellings,Project Acres (Formatted:Underline
(Deleteci:+Project
Deleted:=Allowable Density
IBonus
.. ...... ... ... ... ... ... ... ..
.. ... .. ... ........ ... ... _. ... ... ........ .. ... (Deleted:¶
e. The additional ESOS must meet the following criteria:
i. Meet the standards in Section III.C.3, Open
Space Requirements.
ii. Be natural, undisturbed desert area and cannot
include revegetated areas.
iii. The additional ESOS shall be provided in
common area or separate tracts and cannot be
located on an individual single-family lot.
Draft 3.12.10 8 r.f:sr:aacaiasar
Table III-5
Maximum Density Bonus
Zoning Minimum Area Base Density Maximum
District per Dwelling (D.U.'s/acre Density with
Bonus
R1-300'
300,0000.15 .17
R1-144 144.000 0.3 .36
R1-72 72,000 0.6 .72
R1-43 43,000 1.0 1.2
R1-36 36,000 1.2 1.44
R1-20 20,000 2.2 2.64
R1-10 10,000 4.4 5.28
R1-7 7,000 6.2 7.44
SDH-6 6,000 7.3 8.76
R-4 5,450
8.0 9.6
R-4R 4,250/rental 10.2 12.24
15,000/dwelling 2.9 3.48
R-S 5,450 9.6
8.0
R-6 3,500 12.4 14.88
liNiriPittikgliigiStgGFMOINfir„eka,VILVV-NfffpammpioruItoteqo
panalminisistoulallstwstiggoAmitatrogatongattillatitien
Base (FAR) Maximum FAR
with Bonus
CN .20 .24
C-1 .30 .36
C-2 .40 .48
PS
T-P .50 .60
POS .15 .18
Draft 3.12.10 9
3. Design Standards
A. Development Envelope
1. Development envelopes are required when ESOS is proposed on
individual lots. All impervious surfaces and other improvements
requiring ground disturbance shall be contained within
development envelopes.
GRAPHIC: Development Envelope
2. No clearing, grading,grubbing, or disturbance may occur outside
of the approved development envelopes or within ESOS areas.
Exceptions for underground utility corridors, roads, or regional
drainage improvements may be authorized by the Planning and
Zoning Administrator subject to the following findings and
standards:
a. There is no alternative location outside of an ESOS that can
accommodate the improvement.
b. Improvements are required to insure public safety.
c. Disturbance for underground utility lines must be mitigated as
required in Section NPPSM
d. Additional ESOS areas shall be designated at a ratio of 1:1 to
offset disturbances for drainage or road improvements within
ESOS areas.
3. The specific location of a development envelope shall be shown
on the development plan, subdivision plat, improvement plan, and
Type 1 grading permit. The method of delineating the envelope
boundary must enable precise field verification.
4. A field survey to determine the location of development envelope
boundaries is required at the discretion of the Planning and
Zoning Administrator.
5. The boundary of ESOS or the development envelope shall be
delineated by a temporary, protective fence. Fencing must be:
a. Six foot high vertical posts that are spaced in a manner to
support and connect wire or a similar material as approved
by the Planning and Zoning Administrator.
b. Established prior to construction and remain in place until
construction is complete as determined by the Planning
and Zoning Administrator.
Draft 3.12.10 10
f. Cut or newly exposed rock surfaces shall be treated to
simulate pre-development conditions.
4. Rock outcrops and boulders shall not be encroached upon when
they contain the following characteristics:
a. The rock outcrop or boulder is 20 feet or greater height as
measured from the lowest adjacent natural grade.
(additional M. Goode input pending on ht. criteria).
b. The rock outcrop or boulder is an isolated feature, located
1,000 feet or more from other rock outcrop or boulder
features as defined in Section III.C.2, Rock Outcrops and
Boulders(additional M. Goode input pending on spacing
criteria).
D. Driveways and Access Roads
1. Driveways and access roads must be designed to minimize
grading and disturbance of environmentally sensitive areas.
Shortest distance, direct alignments must be used, unless
avoiding or minimizing impact to Critical or Core Resource
features.
2. No parking or additional circulation areas are permitted outside
the approved construction envelope.
3. Restoration of all disturbed areas is required in accordance with
the standards of Section , NPPSM.
E. Structures
1. For structures on residential lots adjacent to ESOS, or non-
residential and multi-family structures within 200 feet of ESOS,
building materials must meet the following standards:
a. Glass surfaces shall not exceed a reflectivity of %.
b. Exterior finishes shall not exceed a reflectivity of 60%.
c. Materials used for exterior surfaces of all structures shall
match in color, hue, and tone with the surrounding natural
desert setting.
d. Surface materials of walls, retaining walls or fences shall
be similar to and compatible with those of the adjacent
main buildings.
2. All equipment appurtenant to underground facilities, such as
surface mounted utility transformers, pull boxes, pedestal
cabinets, service terminals or other similar on-the-ground facilities,
Draft 3.12.10 12
shall have an exterior treatment that has a reflectivity not to
exceed 60%.
F. Wash and Drainage Crossings
1. Roadway, pathway,fence and utility crossings of natural
watercourses shall be wildlife friendly.
a. (specifications pending)
2. Fences crossing natural watercourses shall be designed in
accordance with the standards and policies specified in the
Town's Drainage Design Criteria.
G. Permanent Walls and Fences
1. No walls,fences, or other barriers may be located so as to impede
wildlife movement through designated ESOS. Walls or fences
shall not enclose or disconnect contiguous ESOS.
2. Fences shall be wildlife friendly and designed in accordance with
Section 24.7.D (RHOD)
3. Walls are not permitted to cross washes of fifty(50)cfs greater
flow in a 100-year event.
4. Walls can be in the form of a view fence that combines solid wall
elements with wrought iron or other open material to permit
unobstructed views.
5. Walls shall satisfy the following criteria:
a. Walls shall not require the removal of protected native
plant specimens and rock outcrops;
b. Walls shall contain ground level openings of at least nine
(9)square feet in area with a dimension of three(3) by
three(3)feet, and be spaced no more than two hundred
(200)feet apart, including openings for drainage ways, in
order to allow wildlife movements and passage of localized
stormwater flows; and
c. Walls shall be built of materials that blend into the rough
textures and rustic character of the vegetation, rocks and
other features of the natural desert setting.
Draft 3.12.10 13
Draft 3.12.10
G. Hillside Area Category
1. Purpose
The Hillside Area category is intended to protect public safety,
conserve scenic sloped and mountainous areas and,when
developed, ensure compatibility with the distinct hillside
topography which is important to the visual and scenic character
of the Town.
2. Applicability
a. The Hillside Area requirements apply to any parcel
containing sloped areas of 15 percent or greater where the
sloped area is greater than 150 feet in length and no less
than 50 feet wide and greater than seven and one-half(7
1/2)feet vertically. (add graphic).
b. Areas of less than 15 percent slope are not restricted by
these Hillside Area requirements.
.................
c. Rock outcrops and boulders, as defined in Section III.C,
Conservation System, are excluded from this Section. See
Section III. and IIID. 3, Design Standards.
3. Sloped Area Analysis
a. When the minimum dimensions and percent of slope as
described above are present, a sloped area analysis shall
be prepared.
b. When land division, subdividing, development plan or other
development approval is requested, all areas of 15%slope
or greater shall be identified by the sloped area analysis.
c. The sloped area analysis,which must be prepared by a
State of Arizona, licensed and registered engineer, shall
identify and map all"Percent Slope"categories in Table III-
5.
d. Digital topographic information meeting a minimum
standard as defined by the Town Engineer, shall be used
to prepare the sloped area analysis. Alternative
information or methodologies may be approved by the
Town Engineer.
4. Conservation Standards
Hillside Areas shall be conserved in the following manner:
#1"--
Draft 3.12.10 1 ;iifLIfiCi34Ah1Eki'iRi 3.Y
,9:as3t•3vs.,:atss:
a. Sloped areas from fifteen (15)to less than twenty-five(25)
percent slope may be developed in a limited manner in
accordance with the standards of this Section, Section III.D
and the OVZCR.
b. In accordance with the Critical Resource designation,
ninety-five(95) percent of sloped areas of twenty-five(25)
percent and greater are to be conserved as ESOS.
..........................
...............................
Exceptions may be approved in accordance with Section
1I1 C 3.C , ESOS Flexibility.
5. General Requirements
a. A development envelope shall be delineated on the
subdivision plat, development and site plan when sloped
areas of 15 percent or greater are present on the plat,
development or site plan. The development envelope shall
be treated as specified in Section I I I D3A.
(Formatted:Indent:Left: 0"
b. When lots or development plans include sloped areas over
15 percent,the areal extent of grading or other ground
disturbance of 15 percent but less than 25 percent, sloped
areas is limited in accordance with Table III-5.
Formatted:List Paragraph, No
c. When proposed lots are comprised entirely of fifteen (15) bullets or numbering
percent slopes or greater,the minimum lot size shall be in
accordance with Table Ill-5. If proposed lots include
multiple slope categories:
4 Formatted:List Paragraph, No
(1) Lot size is determined by the slope category bullets or numbering
comprising the largest percent of the proposed lot, and f Formatted
(2) Grading limits in Table Ill-5 apply to each slope
category on the lot.
Graphic: Example lot with varying slope - (Formatted:Indent:Left: 3.5"
Draft 3.12.10 2
s::'as3t'ys e..at..
TABLE III-5: SLOPE DENSITY AND GRADING LIMITS
Percent Slope Minimum Lot Size Maximum% Maximum
(acres) Graded Building Height(ft)
15<20 1.00 40.0 Per Base Zoning
20<25 2.00 20.0 18
25<33 8.00 5.0 18
•
33.0 and Greater 36.00 4.0 18
*Or as permitted by base zoning,whichever lot size is larger.
d. In determining the areas to be developed, maximum
disturbance limits and specific design criteria must be
considered. Table III-5 indicates the maximum amount of
disturbance to sloped areas. Prioritized criteria for site
planning and the delineation of hillside ESOS and/or
Hillside Conservation Areas are included below.
(1) Subdivision design shall meet the following:
i. Contiguous location of hillside open space to
established open space areas or other ESL
features,
ii. Minimize disturbance of ESL features as prioritized
.........................
in Section III.C3,
iii. Conservation of the largest sloped areas of 15
percent or greater on the site,
iv. Consolidation of hillside and other open space
areas, and
v. Minimize disruption to natural drainage patterns.
(2) Development envelope design on individual lots shall
meet the criteria as listed above, however, replacing
Criteria iii, above,with:
i. Exclude the areas of steepest slope from the
development envelope.
e. After delineation of permissible development areas, all
remaining areas of 25 percent and greater slope shall be
designated as ESOS in accordance with the provisions of
Section III C 3, Open Space Requirements. (note; meaning
it has to meet the minimum size and maintenance
requirements of that section)Areas of 25 percent slope
that do not meet the minimum requirements for ESOS shall
be designated as Hillside Conservation Area.
Draft 3.12.10 3 ?9flE?Cf?Mi'tRE3Y
E:VSIi'3d#tRtit:S
f. Open space identified during individual residential lot
development or open space not meeting the minimum
requirements for ESOS must be designated as Hillside
Conservation Area.
Hillside Conservation Area: Shall mean land area set aside for
conservation of natural slopes greater than 15 percent.
g. If an existing (at the time of adoption of this Ordinance) lot
or parcel does not meet the minimum size requirements of
Table III-5,grading limitations based on percent of slope
from Table III-5 still apply.
h. For property composed entirely of 25 percent or greater
slopes, any proposed lot shall meet the minimum lot size
and maximum grading requirements of Table III-5.
i. Calculations shall be provided indicating the percent of
disturbance, if any,to each slope category described in
Table III-5.
6. Hillside Area Design Standards
a. Development must be in compliance with Section III.D.3,
Design Standards, Subsections A, B, D, E, F and G.
Flexible Development Standards or Cluster Design
standards may be applied in accordance with the
provisions and limitations in Section III.D.
b. Where sloped areas include ridge features, building
rooflines shall not protrude above the height of the ridge,
unless approved by the Town Council in accordance with
the criteria below.
(1) Structures are single story, and no more than 14 feet,
including parapets, above the pre-development grade
of the site,
(2) Roof design is limited to a slope of no greater than 1/2
inch rise per 12 inch horizontal run.
(3) Approved plant materials are installed along exterior
walls of 15 feet or more in length.
New Definition- Ridge: Shall mean a topographic feature
associated with the top of hillsides and mountains having a
continual elevation crest of 150 lineal feet or more and
height of at least 20 feet.
*4
Draft 3.12.10 4
Discussion Point:If stronger ridge line conservation is
desired, following alternate language might be
considered, However there is a concern with _..pushing
construction off the ridge and creating more significant
hillside impacts:with cutting/filling,
"Conserve the ridge line silhouette of significant
topographic features by locating all improvements below
the ridge line and using a finished height that does not
protrude into the silhouette as viewed from nearby public
roads."
c. Cut and fill slopes shall be shielded by structures so as to
not be visible from adjacent properties or public roadways,
or shall be colored or otherwise treated in a manner to
blend with surrounding native soils and rocks.
d. All structures and appurtenances thereto such as a
satellite dishes, shall be earth tone and shall comply with
Section D.3.E, Structures. Colors and exterior finishes
exceeding a reflectivity value of 60%are not permitted.
e. Outdoor storage shall be located within an entirely opaque
barrier designed to match the materials, color, and finish of
the primary structure. Storage may not be visible from
private or public streets or adjacent residential areas.
f. Roof mounted equipment is prohibited unless fully
screened from all neighboring properties. Screening
devices may not exceed permitted building heights as
measured in hillside areas.
7. Building Height
a. As permitted by the underlying zone.
b. For buildings located within identified slope areas of 15
percent of greater, building height shall be measured in the
following manner:
(1) Where building pad elevation is the same or higher
than predevelopment grade due to engineered fill,the
building height contour line method shall be used(as
defined in Chapter 31). Small areas of rugged terrain
shall not increase or reduce building height. Small
areas are those features with a maximum width of
twenty-five(25)feet.
GRAPHIC_building height contour line
Draft 3.12.10 5 iFD{FEFili3<?lS1fSeAE.i.Y
1 ,
•
(2) Where building pad elevation is lower than
predevelopment grade due to cut conditions, building
height is measured from finished grade.
c. Additional building height of 12 feet may be approved in
accordance with Section III.D.2.C, Flexible Development
Standards, if the additional building height does not
protrude above adjacent ridge lines as viewed from public
streets and abutting residential property. Adjacent ridge
lines include ridge features on site or within 150 feet of the
proposed building.
Draft 3.12.10 6
):Rft[Ei?Cfi'4t4S1F7i'ERE.3.Y
53dtl3'!ys I.Rd::!.
1 +
Section 24.2 Hillside Development Zone
A. Introduction
This ordinance seeks to implement the adopted planning goals of this community with regard to
public safety, conservation of resources, community design and open space and recreation.
Oro Valley is surrounded by mountains. These mountainous areas exhibit steep slopes which
may contain unstable rock and soils. Development on potentially unstable soils or rock can be
hazardous to life and property. Development in these areas should utilize construction methods
which ensure slope stabilization and minimize soil erosion.
Further, Oro Valley's rolling desert terrain, containing peaks, ridges and drainageways, is a
valuable scenic resource which should be preserved. Significant peaks and ridges should be
protected in order to preserve the Town's unique visual setting, promote its economic well-being,
and encourage tourism. Regulating the intensity of development according to the natural
characteristics of hillside terrain, such as steepness of slope, significant vegetation and
landforms and soil stability and existing drainage patterns, will allow for sensible development in
hillside areas while minimizing the physical and visual impact of such development.
B. Purpose
This zone provides for the reasonable use of hillside areas and related lands while protecting the
public health, safety, and general welfare by:
1. Determining whether certain types of soil conditions exist (such as loose or easily eroded soils,
or rocky soils), and utilizing appropriate engineering technology to result in stable slopes during
and subsequent to development.
2. Reduction of water runoff and changes in the natural drainage patterns, soil erosion, and rock
slides by minimizing grading and requiring revegetation.
3. Permitting intensity of development compatible with the natural characteristics of hillside terrain,
such as steepness of slope, significant landforms, soil suitability, and existing drainage patterns.
4. Preservation of the scenic quality of the desert and mountain environment through the retention
of significant peaks and ridges in their natural state.
5. Reduction of the physical impact of hillside development by encouraging innovative site and
architectural design, minimizing grading and requiring restoration of graded areas.
6. Provision of safe and convenient vehicular access by encouraging development in the less
steeply sloped terrain.
7. Promoting cost-efficient public services by encouraging development in the less steeply sloped
terrain, thereby minimizing service extensions and utility costs, and maximizing access for all
necessary life safety services.
C. Applicability
The provisions of the Hillside Development Zone (HDZ) apply to development in the areas listed
below:
1. Sloped Areas
a. Any parcel with an average cross slope of 15 percent or containing slopes of 25
percent or greater. Methods of analyzing slope are given in Section 24.2.K.
b. Any parcel containing sloped areas of 25 percent or greater where the sloped area is
greater than 50 feet in any horizontal direction or greater than seven and one-half(7
1/2)feet vertically.
2. Previously Approved Subdivisions
Any recorded subdivision plat approved in compliance with the Pima County Hillside
Development Zone regulations may be developed in compliance with the conditions and
stipulations as approved. If the plat is resubdivided after the effective date of this
ordinance, September 17, 1993, it must comply with all provisions of the Oro Valley HDZ
currently in effect.
3. Exceptions
a. The HDZ regulations shall apply to all property described in Section 24.2.0 except
where the development standards prevent the reasonable utilization of property as
determined by the Board of Adjustment through the approval of a variance. All HDZ
applicability appeals shall be heard by the Board of Adjustment in conformance with
the variance procedures established in Section 21.6.
b. The HDZ regulations do not apply to the paving of an existing driveway located on
property with HDZ applicability.
c. Lots within existing, approved subdivisions on the effective date of this ordinance,
and subdivision plats which have been submitted prior to the effective date of this
ordinance shall not be subject to the provisions of this ordinance.
D. Permitted Uses
Any use permitted by the underlying zone is allowed.
E. Review Required
All development will require subdivision plat or development plan approval, in accordance with
the Oro Valley Zoning Code Revised, prior to the granting of a permit for grubbing, grading,
excavation, or construction.
F. Development Criteria
The following development criteria apply to all parcels that are affected by this zone. Any parcel
created must meet slope/size requirements of Table 24-1. All development is subject to the Oro
Valley Grading Ordinance.
1. Single-Family Residential Development
a. This paragraph applies to an existing parcel where no land division has occurred, nor
is land division proposed, since the adoption of this ordinance. The average cross
slope (ACS) is calculated for the entire parcel. If the ACS is 15 percent or greater,
Columns A and D of Table 24-1 apply.
b. This paragraph applies to any parcel of property or lot where land division is
proposed or has occurred since the adoption of this ordinance. The average cross
slope is calculated for the parcel prior to land division. If the ACS is 15 percent or
greater, columns A and C of Table 24-1 apply. Natural open space may be
designated on the parcel in accordance with Section 24.2.G, to reduce the ACS
percentage. Such natural open space will be excluded from the ACS calculation, but
will be included in the land area for the parcel.
i. If a subdivision plat is required, all 25 percent or greater slopes (as defined in
24.2.C.1.b)within the proposed lots, except for those within natural open space
areas, are delineated. These sloped areas then determine the design of the
development according to the following criteria.
a) Where the areas of 25 percent or greater slope are located outside the
buildable area,the minimum lot size requirements of the underlying zone
apply.The buildable area may be redefined by the applicant to exclude
areas of steeper slope in order to comply with this requirement. Grading
may occur only within the buildable area and access to the buildable area.
Grading for roadway or driveway access shall not cross a 25 percent or
greater sloped area unless no alternative routes exist. Driveway clearing
and grading may be no wider than 30 feet.
b) Where the buildable area contains areas of 25 percent or greater slope,
the minimum size required for that proposed lot is 43,560 square feet
unless a greater size is required by the underlying zone. The amount of
grading permitted is the amount indicated in Column D of Table 24-1,
based on the area of the lot, Column B.
ii. If a subdivision plat is not required, the land area of each parcel created must
comply with Columns A, B and D of Table 24-1.
2. Multi-Family Residential Development
a. All grading is subject to the provisions of the Oro Valley Grading Ordinance.
b. The ACS is calculated for the entire parcel. If the ACS is 15 percent or greater,
columns A, B, C, and D of Table 24-1 apply.
c. Natural open space may be designated on the parcel, in accordance with Section
24.2.G to reduce the ACS percentage. Such natural open space will be excluded
from the ACS calculation, but will be included for density calculation. If the ACS of the
remaining portion of the parcel, after natural open space designation is:
i. Less than 15 percent and contains no areas of 25 percent or greater slope,
100 percent of that portion may be graded.
ii. Less than 15 percent, but contains areas of 25 percent or greater slopes, no
more than 80 percent of that remaining portion may be graded.
iii. Fifteen percent or greater, columns B, C, and D of Table 24-1 apply, based on
the entire area of the parcel.
3. Non-Residential Development
a. All grading is subject to the provisions of the Oro Valley Grading Ordinance.
b. The ACS is calculated for the entire parcel. If the ACS is 15 percent or greater,
columns A, B, and D of Table 24-1 apply.
c. Natural open space may be designated on the parcel, in accordance with Section
24.2.G, to reduce the ACS percentage. If the ACS of the remaining portion of the
parcel is:
i. Less than 15 percent and contains no areas of 25 percent or greater slope,
100 percent of that portion may be graded.
ii. Less than 15 percent, but contains areas of 25 percent or greater slope, no
more than 80 percent of that remaining portion may be graded.
iii. Fifteen percent or greater, Columns B and D of Table 24-1 apply, based on
the entire area of the parcel.
4. Mixed Development
When a mix of development is proposed, i.e., a combination of residential, commercial, office, or
industrial land uses, each use must meet all criteria for that development, as required by this Section.
1
I
TABLE 24-1: SLOPE DENSITY REQUIREMENTS
A B C D
Minimum Area* Density* Maximum Grading
Average Cross Slope (Acres/Dwelling or (Dwellings/Acre) (Percentage)
Structure)
Less Than 15 as Permitted by Underlying Zoning
15.0-15.9 1.00 1.00 40.0
16.0-16.9 1.00 1.00 40.0
17.0-17.9 1.25 .80 32.0
18.0-18.9 1.37 .73 29.2
19.0-19.9 1.50 .67 21.3
20.0-20.9 2.00 .50 20.0
21.0-21.9 2.25 .44 17.7
22.0-22.9 2.50 .40 16.0
23.0-23.9 3.50 .29 13.3
24.0-24.9 4.50 .22 11.9
25.0-25.9 6.00 .17 9.3
26.0-26.9 7.00 .14 9.3
27.0-27.9 8.60 .12 9.3
28.0-28.9 10.40 .09 9.3
29.0-29.9 12.80 .08 9.3
30.0-30.9 16.00 .06 8.8
31.0-31.9 23.50 .04 6.7
32.0-32.9 31.00 .03 6.7
33.0 and Greater 36.00 .027 4.0
*Or as permitted by underlying zoning,whichever density is less.
G. Natural Open Space
Natural open space (see Chapter 31 for definition) may be designated on any parcel, subject to
the following criteria:
1. Development other than hiking trails will not be permitted within the legally described boundaries
of natural open space in the Hillside Development Zone. Access roads, other than driveways, are
0 not permitted within natural open space.
2. Natural open space will be delineated in a surveyable manner on the preliminary and final plats
it of a subdivision, or on the development plan, and shall be designated by legal description on a
document recorded with the Pima County Recorder.
3. Natural open space may be designated as a deed restricted portion of a privately owned lot, or
as a separate land parcel. This parcel may be under the ownership of a homeowner's
association, or deeded to any organization willing to accept responsibility for the perpetual
preservation of the natural open space, subject to approval and acceptance by the Town of Oro
Valley.
4. To protect natural open space, covenants which run with the land will be provided in favor of the
Town of Oro Valley and all owners with record interest in the natural area.
5. If natural open space is designated on parcels four (4) acres or more, at least one (1) such
natural open space area shall be a minimum of one-half(1/2)acres in size.
H. Hillside Site Improvement Standard
1. Building Height
a. As permitted by the underlying zone. If the building also falls within the boundaries of
other overlay zones, the more restrictive of the requirements applies. In order to
eliminate large amounts of cut and fill, segments of buildings may be designed at
varying elevations according to the slope of the land. For parcels with HDZ
applicability per Section 242, building height shall be measured, using a building
height contour line (as defined in Chapter 31, Building Height Contour Line).
b. A variance to maximum building height may be approved by the Board of Adjustment.
Additionally, the Development Review Board shall review any structure over 18 feet
in the HDZ and may approve said structure if such approval provides a better method
of building to the land and is no more detrimental to adjacent properties than strict
adherence to the development standards of the underlying district would allow. Such
variance, as granted by the Board of Adjustment, shall be in compliance with the
provisions of Section 21.6 of the Oro Valley Zoning Code Revised. Development
Review Board review and approval shall be required prior to the issuance of any
grading or building permits in accordance with Section 22.5.
2. Site Improvement Standard
All proposed site work (see Site definition in Chapter 31), including grading, shall comply
with the Development Standards contained in the Grading Ordinance.
3. Color
All exposed exterior walls and roofs of structures, retaining walls and accessory structures
shall utilize the predominant natural colors found on the parcel. Satellite dishes shall be
earth tone or black. White is not permitted. Color approval by the Planning and Zoning
Administrator shall be required for all HDZ development. Appeals of the Planning and
Zoning Administrator's decision may be filed by the applicant and will be heard by the
Development Review Board within 35 days from the date of appeal. The decision of the
Development Review Board shall be final.
I. Maintenance and Protection
The Planning and Zoning Administrator may, prior to recordation of a subdivision plat or issuance
_ of building permits, require measures, such as covenants, assurances, or homeowner's
associations, as are necessary to ensure the long term maintenance of slope control measures.
J. Enforcement
4
1. The developer and/or property owner shall be responsible for the following:
a. Submitting average natural cross slope and sloped area analyses, certified by a
qualified registrant, for review and verification by the Town Engineer or his/her
designee.
b. Surveying, staking, and inspection of the property by a qualified registrant to
determine compliance with the provisions of this Section.
c. On-site enforcement by certifying to the Town Engineer that the development
complies with Section 24.2 Hillside Development Zone during the period of
development.
2. If violation of any provision of the Hillside Development Zone occurs, the property owner shall be
responsible for bringing the violation into compliance with the requirements of this zone. This
may require restoration of the site as closely as possible to its original undisturbed condition,
topography, and vegetation, in order to remove the violation.
K. Slope Analysis Standard
1. Average Cross Slope Analysis
The Average Cross Slope (ACS) of a site shall be determined by a qualified registrant in
the following manner:
a. The site is depicted on a topographic map of the existing terrain, prior to any grading,
grubbing, clearing, excavation, or modification, utilizing a scale no smaller than one
(1) inch equals 100 feet, with the following contour intervals:
i. For sites less than five (5)acres, a contour interval of two(2)feet;
ii. For sites five (5) acres and greater, a contour interval of two (2)feet or five (5)
feet.
b. The length of each contour line contained within the site boundaries on the map is
measured by means of a mechanical device such as a map wheel or digitizer. This
actual length is converted to scale length in feet. For example, at a scale of one (1)
inch equals 40 feet(1"=40'), a contour line with an actual map length of six and one-
half(6 3/4) inches represents a line 260 feet long (6.5 x 40=260).
c. The sum of the lengths (L) of all contour lines is multiplied by the contour interval (I)
in feet.
d. The result is multiplied by the factor .0023, which converts the square footage of the
scale map to acres.
e. This result is then divided by the area (A)of the site in acres.
f. This process is mathematically represented by the formula
ACS = (I) (L) (.0023)
(A)
g. The answer is the percentage of the ACS for the site.
2. Sloped Area Analysis
In addition to ACS requirements, any parcel containing areas with a slope of 25 percent or
more shall have HDZ applicability as stated in Section 24.2.C. A sloped area analysis,
which must be prepared by a qualified registrant, shall identify individual slopes for design
and review purposes. A detailed methodology for performing sloped area analysis is
available from the Planning and Zoning Department.
_1
. .
• Section 24.2 Hillside Development Zone
A. Introduction
This ordinance seeks to implement the adopted planning goals of this community with regard to
public safety, conservation of resources, community design and open space and recreation.
Oro Valley is surrounded by mountains. These mountainous areas exhibit steep slopes which
may contain unstable rock and soils. Development on potentially unstable soils or rock can be
hazardous to life and property. Development in these areas should utilize construction methods
which ensure slope stabilization and minimize soil erosion.
Further, Oro Valley's rolling desert terrain, containing peaks, ridges and drainageways, is a
valuable scenic resource which should be preserved. Significant peaks and ridges should be
protected in order to preserve the Town's unique visual setting, promote its economic well-being,
and encourage tourism. Regulating the intensity of development according to the natural
characteristics of hillside terrain, such as steepness of slope, significant vegetation and
landforms and soil stability and existing drainage patterns, will allow for sensible development in
hillside areas while minimizing the physical and visual impact of such development.
B. Purpose
This zone provides for the reasonable use of hillside areas and related lands while protecting the
public health, safety, and general welfare by:
1. Determining whether certain types of soil conditions exist (such as loose or easily eroded soils,
or rocky soils), and utilizing appropriate engineering technology to result in stable slopes during
and subsequent to development.
2. Reduction of water runoff and changes in the natural drainage patterns, soil erosion, and rock
slides by minimizing grading and requiring revegetation.
3. Permitting intensity of development compatible with the natural characteristics of hillside terrain,
such as steepness of slope, significant landforms, soil suitability, and existing drainage patterns.
4. Preservation of the scenic quality of the desert and mountain environment through the retention
of significant peaks and ridges in their natural state.
5. Reduction of the physical impact of hillside development by encouraging innovative site and
architectural design, minimizing grading and requiring restoration of graded areas.
6. Provision of safe and convenient vehicular access by encouraging development in the less
steeply sloped terrain.
7. Promoting cost-efficient public services by encouraging development in the less steeply sloped
terrain, thereby minimizing service extensions and utility costs, and maximizing access for all
necessary life safety services.
. .
C. Applicability
•
The provisions of the Hillside Development Zone (HDZ) apply to development in the areas listed
below:
1. Sloped Areas
a. Any parcel with an average cross slope of 15 percent or containing slopes of 25
percent or greater. Methods of analyzing slope are given in Section 24.2.K.
b. Any parcel containing sloped areas of 25 percent or greater where the sloped area is
greater than 50 feet in any horizontal direction or greater than seven and one-half(7
1/2)feet vertically.
2. Previously Approved Subdivisions
Any recorded subdivision plat approved in compliance with the Pima County Hillside
Development Zone regulations may be developed in compliance with the conditions and
stipulations as approved. If the plat is resubdivided after the effective date of this
ordinance, September 17, 1993, it must comply with all provisions of the Oro Valley HDZ
currently in effect.
3. Exceptions
a. The HDZ regulations shall apply to all property described in Section 24.2.0 except
where the development standards prevent the reasonable utilization of property as
determined by the Board of Adjustment through the approval of a variance. All HDZ
applicability appeals shall be heard by the Board of Adjustment in conformance with
the variance procedures established in Section 21.6.
b. The HDZ regulations do not apply to the paving of an existing driveway located on
property with HDZ applicability.
c. Lots within existing, approved subdivisions on the effective date of this ordinance,
and subdivision plats which have been submitted prior to the effective date of this
ordinance shall not be subject to the provisions of this ordinance.
D. Permitted Uses
Any use permitted by the underlying zone is allowed.
E. Review Required
All development will require subdivision plat or development plan approval, in accordance with
the Oro Valley Zoning Code Revised, prior to the granting of a permit for grubbing, grading,
excavation, or construction.
F. Development Criteria
The following development criteria apply to all parcels that are affected by this zone. Any parcel
created must meet slope/size requirements of Table 24-1. All development is subject to the Oro
Valley Grading Ordinance.
1. Single-Family Residential Development
a. This paragraph applies to an existing parcel where no land division has occurred, nor
is land division proposed, since the adoption of this ordinance. The average cross
slope (ACS) is calculated for the entire parcel. If the ACS is 15 percent or greater,
Columns A and D of Table 24-1 apply.
b. This paragraph applies to any parcel of property or lot where land division is
proposed or has occurred since the adoption of this ordinance. The average cross
slope is calculated for the parcel prior to land division. If the ACS is 15 percent or
greater, columns A and C of Table 24-1 apply. Natural open space may be
designated on the parcel in accordance with Section 24.2.G, to reduce the ACS
percentage. Such natural open space will be excluded from the ACS calculation, but
will be included in the land area for the parcel.
i. If a subdivision plat is required, all 25 percent or greater slopes (as defined in
24.2.C.1.b)within the proposed lots, except for those within natural open space
areas, are delineated. These sloped areas then determine the design of the
development according to the following criteria.
a) Where the areas of 25 percent or greater slope are located outside the
buildable area, the minimum lot size requirements of the underlying zone
apply.The buildable area may be redefined by the applicant to exclude
areas of steeper slope in order to comply with this requirement. Grading
may occur only within the buildable area and access to the buildable area.
Grading for roadway or driveway access shall not cross a 25 percent or
greater sloped area unless no alternative routes exist. Driveway clearing
and grading may be no wider than 30 feet.
b) Where the buildable area contains areas of 25 percent or greater slope,
the minimum size required for that proposed lot is 43,560 square feet
unless a greater size is required by the underlying zone. The amount of
grading permitted is the amount indicated in Column D of Table 24-1,
based on the area of the lot, Column B.
ii. If a subdivision plat is not required, the land area of each parcel created must
comply with Columns A, B and D of Table 24-1.
2. Multi-Family Residential Development
a. All grading is subject to the provisions of the Oro Valley Grading Ordinance.
b. The ACS is calculated for the entire parcel. If the ACS is 15 percent or greater,
columns A, B, C, and D of Table 24-1 apply.
c. Natural open space may be designated on the parcel, in accordance with Section
24.2.G to reduce the ACS percentage. Such natural open space will be excluded
from the ACS calculation, but will be included for density calculation. If the ACS of the
remaining portion of the parcel, after natural open space designation is:
i. Less than 15 percent and contains no areas of 25 percent or greater slope,
100 percent of that portion may be graded.
ii. Less than 15 percent, but contains areas of 25 percent or greater slopes, no
more than 80 percent of that remaining portion may be graded.
iii. Fifteen percent or greater, columns B, C, and D of Table 24-1 apply, based on
the entire area of the parcel.
3. Non-Residential Development
a. All grading is subject to the provisions of the Oro Valley Grading Ordinance.
b. The ACS is calculated for the entire parcel. If the ACS is 15 percent or greater,
columns A, B, and D of Table 24-1 apply.
c. Natural open space may be designated on the parcel, in accordance with Section
24.2.G, to reduce the ACS percentage. If the ACS of the remaining portion of the
parcel is:
i. Less than 15 percent and contains no areas of 25 percent or greater slope,
100 percent of that portion may be graded.
ii. Less than 15 percent, but contains areas of 25 percent or greater slope, no
more than 80 percent of that remaining portion may be graded.
iii. Fifteen percent or greater, Columns B and D of Table 24-1 apply, based on
the entire area of the parcel.
4. Mixed Development
When a mix of development is proposed, i.e., a combination of residential, commercial, office, or
industrial land uses, each use must meet all criteria for that development, as required by this Section.
TABLE 24-1: SLOPE DENSITY REQUIREMENTS
A B C D
Minimum Area* Density* Maximum Grading
Average Cross Slope (Acres/Dwelling or (Dwellings/Acre) (Percentage)
Structure)
Less Than 15 as Permitted by Underlying Zoning
15.0-15.9 1.00 1.00 40.0
16.0-16.9 1.00 1.00 40.0
17.0-17.9 1.25 .80 32.0
18.0-18.9 1.37 .73 29.2
19.0-19.9 1.50 .67 21.3
20.0-20.9 2.00 .50 20.0
21.0-21.9 2.25 .44 17.7
22.0-22.9 2.50 .40 16.0
23.0-23.9 3.50 .29 13.3
24.0-24.9 4.50 .22 11.9
25.0-25.9 6.00 .17 9.3
26.0-26.9 7.00 .14 9.3
27.0-27.9 8.60 .12 9.3
28.0-28.9 10.40 .09 9.3
29.0-29.9 12.80 .08 9.3
30.0-30.9 16.00 .06 8.8
31.0-31.9 23.50 .04 6.7
32.0-32.9 31.00 .03 6.7
33.0 and Greater 36.00 .027 4.0
*Or as permitted by underlying zoning, whichever density is less.
G. Natural Open Space
Natural open space (see Chapter 31 for definition) may be designated on any parcel, subject to
the following criteria:
1. Development other than hiking trails will not be permitted within the legally described boundaries
of natural open space in the Hillside Development Zone. Access roads, other than driveways, are
not permitted within natural open space.
2. Natural open space will be delineated in a surveyable manner on the preliminary and final plats
• of a subdivision, or on the development plan, and shall be designated by legal description on a
document recorded with the Pima County Recorder.
3. Natural open space may be designated as a deed restricted portion of a privately owned lot, or
as a separate land parcel. This parcel may be under the ownership of a homeowner's
association, or deeded to any organization willing to accept responsibility for the perpetual
preservation of the natural open space, subject to approval and acceptance by the Town of Oro
Valley.
4. To protect natural open space, covenants which run with the land will be provided in favor of the
Town of Oro Valley and all owners with record interest in the natural area.
5. If natural open space is designated on parcels four (4) acres or more, at least one (1) such
natural open space area shall be a minimum of one-half(1/2) acres in size.
H. Hillside Site Improvement Standard
1. Building Height
a. As permitted by the underlying zone. If the building also falls within the boundaries of
other overlay zones, the more restrictive of the requirements applies. In order to
eliminate large amounts of cut and fill, segments of buildings may be designed at
varying elevations according to the slope of the land. For parcels with HDZ
applicability per Section 24.2, building height shall be measured, using a building
height contour line (as defined in Chapter 31, Building Height Contour Line).
b. A variance to maximum building height may be approved by the Board of Adjustment.
Additionally, the Development Review Board shall review any structure over 18 feet
in the HDZ and may approve said structure if such approval provides a better method
of building to the land and is no more detrimental to adjacent properties than strict
adherence to the development standards of the underlying district would allow. Such
variance, as granted by the Board of Adjustment, shall be in compliance with the
provisions of Section 21.6 of the Oro Valley Zoning Code Revised. Development
Review Board review and approval shall be required prior to the issuance of any
grading or building permits in accordance with Section 22.5.
2. Site Improvement Standard
All proposed site work (see Site definition in Chapter 31), including grading, shall comply
with the Development Standards contained in the Grading Ordinance.
3. Color
All exposed exterior walls and roofs of structures, retaining walls and accessory structures
shall utilize the predominant natural colors found on the parcel. Satellite dishes shall be
earth tone or black. White is not permitted. Color approval by the Planning and Zoning
Administrator shall be required for all HDZ development. Appeals of the Planning and
Zoning Administrator's decision may be filed by the applicant and will be heard by the
Development Review Board within 35 days from the date of appeal. The decision of the
Development Review Board shall be final.
I. Maintenance and Protection
The Planning and Zoning Administrator may, prior to recordation of a subdivision plat or issuance
of building permits, require measures, such as covenants, assurances, or homeowner's
associations, as are necessary to ensure the long term maintenance of slope control measures.
J. Enforcement
1. The developer and/or property owner shall be responsible for the following:
a. Submitting average natural cross slope and sloped area analyses, certified by a
qualified registrant, for review and verification by the Town Engineer or his/her
designee.
b. Surveying, staking, and inspection of the property by a qualified registrant to
determine compliance with the provisions of this Section.
c. On-site enforcement by certifying to the Town Engineer that the development
complies with Section 24.2 Hillside Development Zone during the period of
development.
2. If violation of any provision of the Hillside Development Zone occurs, the property owner shall be
responsible for bringing the violation into compliance with the requirements of this zone. This
may require restoration of the site as closely as possible to its original undisturbed condition,
topography, and vegetation, in order to remove the violation.
K. Slope Analysis Standard
1. Average Cross Slope Analysis
The Average Cross Slope (ACS) of a site shall be determined by a qualified registrant in
the following manner:
a. The site is depicted on a topographic map of the existing terrain, prior to any grading,
grubbing, clearing, excavation, or modification, utilizing a scale no smaller than one
(1) inch equals 100 feet,with the following contour intervals:
i. For sites less than five (5) acres, a contour interval of two(2)feet;
ii. For sites five (5) acres and greater, a contour interval of two (2)feet or five (5)
feet.
b. The length of each contour line contained within the site boundaries on the map is
measured by means of a mechanical device such as a map wheel or digitizer. This
actual length is converted to scale length in feet. For example, at a scale of one (1)
inch equals 40 feet(1" =40'), a contour line with an actual map length of six and one-
half(6 3/4) inches represents a line 260 feet long (6.5 x 40=260).
c. The sum of the lengths (L) of all contour lines is multiplied by the contour interval (I)
in feet.
d. The result is multiplied by the factor .0023, which converts the square footage of the
scale map to acres.
e. This result is then divided by the area (A)of the site in acres.
f. This process is mathematically represented by the formula
ACS = (I) (L) (.0023)
(A)
g. The answer is the percentage of the ACS for the site.
2. Sloped Area Analysis
• r
In addition to ACS requirements, any parcel containing areas with a slope of 25 percent or
more shall have HDZ applicability as stated in Section 24.2.C. A sloped area analysis,
which must be prepared by a qualified registrant, shall identify individual slopes for design
and review purposes. A detailed methodology for performing sloped area analysis is
available from the Planning and Zoning Department.