HomeMy WebLinkAboutPackets - Stormwater Utillity Commission (208)
AGENDA
STORMWATER UTILITY COMMISSION
STUDY SESSION
APRIL 16, 2026
FIELD LOCATIONS
STUDY SESSION AT OR AFTER 7:30 AM
CALL TO ORDER
ROLL CALL
STUDY SESSION AGENDA
1.DISCUSSION DURING TOUR OF STORMWATER RELATED SITES THROUGHOUT THE TOWN
The following locations and tentative times will be toured:
• 7:30 a.m. – Start at Oro Valley Town Hall, 11000 N La Cañada Dr.
• 1. 7:40 a.m. – Unknown Wash Along Southbound N La Cañada Dr (La Cañada Noise Wall)
• 2. 8:05 a.m. – Lambert Lane Improvements at La Cholla and Sierra Wash
• 3. 8:25 a.m. – Sierra Wash at Glover
• 4. 8:45 a.m. – Sierra Wash at Via Mandarina
• 5. 9:05 a.m. – Sierra Wash at Naranja Dr
• 6. 9:30 a.m. – Catalina Ridge Channel Ramp and New Ramp Location
• 7. 9:55 a.m. – Highland Mobile Home Park
• 8. 10:15 a.m. – Gravel Pit Wash at N Pomegranate Dr
• 9. 10:35 a.m. – Mutterers Wash at Greenock Dr
• 10. 11:00 a.m. – Shadow Mountain Dr, 300' North of W Spring Valley Dr
• 11. 11:25 a.m. – Nanini Wash at N Paseo Del Norte
• 12. 12:00 p.m. – Lunch stop
ADJOURNMENT
There will be no public comment during this study session.
POSTED: 4/9/26 at 5:00 p.m. by ck
POSTED: 4/9/26 at 5:00 p.m. by ck
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.
Stormwater Utility Commission 1.
Meeting Date:04/16/2026
Requested by: Dennis Roberts, Public Works Submitted By:Yarina Hynd, Public Works
SUBJECT:
DISCUSSION DURING TOUR OF STORMWATER RELATED SITES THROUGHOUT THE TOWN
The following locations and tentative times will be toured:
• 7:30 a.m. – Start at Oro Valley Town Hall, 11000 N La Cañada Dr.
• 1. 7:40 a.m. – Unknown Wash Along Southbound N La Cañada Dr (La Cañada Noise Wall)
• 2. 8:05 a.m. – Lambert Lane Improvements at La Cholla and Sierra Wash
• 3. 8:25 a.m. – Sierra Wash at Glover
• 4. 8:45 a.m. – Sierra Wash at Via Mandarina
• 5. 9:05 a.m. – Sierra Wash at Naranja Dr
• 6. 9:30 a.m. – Catalina Ridge Channel Ramp and New Ramp Location
• 7. 9:55 a.m. – Highland Mobile Home Park
• 8. 10:15 a.m. – Gravel Pit Wash at N Pomegranate Dr
• 9. 10:35 a.m. – Mutterers Wash at Greenock Dr
• 10. 11:00 a.m. – Shadow Mountain Dr, 300' North of W Spring Valley Dr
• 11. 11:25 a.m. – Nanini Wash at N Paseo Del Norte
• 12. 12:00 p.m. – Lunch stop
RECOMMENDATION:
N/A
EXECUTIVE SUMMARY:
N/A
BACKGROUND OR DETAILED INFORMATION:
N/A
FISCAL IMPACT:
N/A
SUGGESTED MOTION:
N/A
Attachments
2026 Field Trip Map
SWU Field Trip Handout
^_
INA
ORACLE
LA CHOLLA
LA CANADA
MAGEE
SHANNON
LAMBERT
1ST
TANGERINE
NARANJA
OVERTON
HARDY
CHRISTIE
NORTHERN
LINDA VISTA
MONA LISA
CALLE CONCORDIA
PUSCH VIEW
CORTARO FARMS
1ST
HARDY
MAGEE
Stop Number 1
Stop Number 9
Stop Number 8Stop Number 7
Stop Number 6
Stop Number 3
Stop Number 4
Stop Number 5
Stop Number 2
Stop Number 11
Stop Number 10
2026 Stormwater Utility Field Trip Stops
Starting PointOro Valley Town Hall
Legend
Field Trip Stops
Stop Number
Stop Number 1
Stop Number 2
Stop Number 3
Stop Number 4
Stop Number 5
Stop Number 6
Stop Number 7
Stop Number 8
Stop Number 9
Stop Number 10
Stop Number 11
^_Starting Point (Oro Valley Town Hall)
Major Streets ¯Miles00.5 1
STORMWATER UTILITY FIELD TOUR
PROJECT DESCRIPTION HANDOUT
Dennis E. Roberts, P.E., CFM
Stormwater Utility Division Manager
Stormwater Utility - Public Works Department
Unknown Wash
along southbound
N La Canada Dr
Status: Active
Last Revised: 12/1/25
Project Overview
Scour extending along the noise wall on the west side of N La Canada Dr with scour
depths of 5 to 6 ft below the wall footing. The channel runs through a steep and
narrow stretch upstream of this location and bends towards the wall where the
scour is occurring. The channel enter a more open and wide stretch downstream of
this location and stabilizes before entering a drop structure and storm drain.
Exposed drip irrigation lines do not appear to be in use. Lack of vegetation or bank
protection on the bank along the noise wall has clearly led to this problem.
Proposed Improvements
Channel realignment. The channel will be moved away from the wall in this
location and a straight channel section will be created. The bend in the channel will
be removed. Cut from the west side can be used as fill on the east side of the
channel. Additional fill is likely required.
Bank protection. The bank along the noise wall requires bank protection. An
assessment can determine the best option, but riprap is required at a minimum.
Cost Estimate
Total Estimated Cost: [Insert total once confirmed]
(32.391200, -110.995958)
La Canada Noise Wall
Lambert Lane
Improvements
Status: Complete Phase 1 June 2019, Phase 2 April 2020
Last Revised: 3/11/26
Project Overview
Stormwater from an La Cholla and Sierra Wash wash repeatedly overtops Lambert Lane,
causing high-velocity flows that erode the unpaved shoulder, threaten roadway stability,
damage buried utilities, and require frequent closures and maintenance; reconstruction was
necessary to prevent erosion, protect infrastructure, reduce detours, and ensure the
roadway functions safely during storm events.
Proposed Improvements
•Stabilize downstream shoulder to prevent erosion at the dip crossing.
•Excavate, grade, and prepare subgrade for new structural improvements.
•Install concrete, reinforcing steel, and gabion energy dissipaters.
•Rebuild eastbound shoulder with aggregate base and asphalt.
•Add guardrail and complete incidental safety and site-restoration work.
Cost Estimate
Total Estimated Cost: Phase 1 - $221,615 and Phase 2 - $235,660.72
State of Arizona Disaster Funds (DEMA SEC 19-4 Funds $225,410.72
(32.395203, -111.016095)
BEFORE
AFTER
Lambert Lane Improvement
Lambert Lane Improvement
Lambert Lane Improvement
Lambert Lane Improvement
Project Overview
The outlet of the existing box culvert is experiencing downcutting and erosion, which
compromises channel stability and increases long-term maintenance needs. Access to the
channel is approximately 120 feet from the culvert centerline, presenting logistical challenges
for construction.
Proposed Improvements
Channel Stabilization: Address downcutting at the culvert outlet to restore hydraulic function
and prevent further erosion.
Riprap & Curb Replacement: Replace damaged riprap and curb sections to reinforce channel
protection.
Access Considerations: Develop construction access approximately 120 feet downstream to
facilitate equipment mobilization.
Construction Plans: Plans are submitted to CED for permitting, ensuring readiness for
implementation once funding is secured.
Cost Estimate
Federal Funding: $234,117
Town of Oro Valley Contribution: $78,040
Total Estimated Cost: $312,157
(32.416993, -111.007363)
Sierra Wash
at
W Glover Rd.
In partnership with
Status: Active
Last Revised: 12/1/25
Project Overview
Road culvert with an elevation drop on the outlet side. Ongoing scour and erosion led to a
significant drop of 2-3 feet as of late 2021. A concrete drop structure, gabion mattress, and
gabion end sill have been implemented on the outlet side to reinforce and stabilize the
ground in this flow area.
Completed Improvements
Reinfoce outlet and provide energy dissipation. The site was retrofitted with a concrete
drop structure, gabion mattress, and gabion end sill to provide energy dissipation, scour
protection, and stabilize the ground on the outlet side of this culvert.
Cost Estimate
Federal Funding: $210,990.75
Town of Oro Valley Contribution: $82,983.05
Total Cost: $293,973.80
(32.413464, -111.008108)
Status: Complete June 2025
Last Revised: 3/2/26
Sierra Wash at
Via Mandarina
In partnership with
BEFORE
AFTER
Sierra Wash at Via Mandarina
Sierra Wash
Sierra Wash at Via Mandarina
Sierra Wash at Via Mandarina
Project Overview
Road culvert with an elevation drop on the outlet side. Ongoing scour and erosion led to a
significant drop of 4-5 feet as of December 2017. A concrete drop structure, gabion mattress, and
gabion end sill have been implemented on the outlet side to reinforce and stabilize the ground in
this flow area.
Completed Improvements
Reinfoce outlet and provide energy dissipation. The rock-faced concrete paving was replaced
with a concrete drop structure, gabion mattress, and gabion end sill to provide energy
dissipation, scour protection, and stabilize the ground on the outlet side of this culvert.
Cost Estimate
Federal Funding: $309,000
Town of Oro Valley Contribution: $103,000
Total Cost: $412,000
(32.409771, -111.008350)
Status: Complete May 2023
Last Revised: 3/2/26
Sierra Wash at
W Naranja Dr
In partnership with
BEFORE
AFTER
Sierra Wash at W Naranja Dr
Sierra Wash at W Naranja
Sierra Wash at W Naranja Dr Rain Event
(2021-08-10)
Sierra Wash at W Naranja
Catalina Ridge
Channel Access at
N Avenida Vallejo
Status: Complete May 2023
Last Revised: 3/11/26
Project Overview
Sedimentation collecting within the channel with no access to remove the sediment. Ramp
installation necessary to remove sediment, repair channel bottom, and allow infrastructure
to work as intended.
Proposed Improvements
Create access ramp.Design is underway for an access ramp near N Avenida Vallejo into the
channel for routine maintenance access.
Remove sediment from culvert. Sediment removal is required from the RCBC at North
Avenida Vallejo to provide full flow capacity.
Reduce sediment accumulation. The channel bottom can be lined with concrete to reduce
the amount of sediment accumulation in the channel.
Cost Estimate
Total Estimated Cost: $290,502.24
(32.407867, -110.963798)
BEFORE
AFTER
Catalina Ridge Channel Access at N Avenida
Vallejo
Catalina Ridge Channel Access at N Avenida
Vallejo
Catalina Ridge Channel Access at N Avenida
Vallejo
Catalina Ridge Channel Access at N Avenida
Vallejo
Unknown Wash
along southbound
N Avenida Vallejo
Catalina Ridge
Status: Active
Last Revised: 12/1/25
Project Overview
Channel protected with rock-faced concrete has significant sediment accumulation
measured up to 9 inches deep in several locations. Sediment accumulation is a
problem from the start of the channel at E Naranja Dr through to the terminus at
Canada del Oro Wash. The RCBC at E Naranja Dr was observed to have the most
significant sediment accumulation with only 20 inches of vertical clearance
remaining on the inlet side, and 39 inches of vertical clearance remaining on the
outlet side.
Proposed Improvements
Remove sediment from culvert. Sediment removal is required from the RCBC at E
Naranja Drive to provide full flow capacity.
Reduce sediment accumulation. The channel bottom can be lined with concrete to
reduce the amount of sediment accumulation in the channel. Another option is the
upstream sediment sources can be identified and mitigated.
Cost Estimate
Total Estimated Cost: $388K±
(32.407372, -110.963693)
Project Description
Undersized channel through the mobile home park requires increased capacity and
concrete lining. A large sediment basin has been recently installed upstream of the site at
the Naranja Trails subdivision site, and the improvements for this CIP project will tie into the
sediment basin. There are several steep drop structures downstream of the site. The
elevation difference in the channel between the sediment basin and W Matterhorn St will
be a limiting factor for the design.
Proposed Improvements
Increase channel capacity.Increase channel depth, reinforce banks, and line the channel
with concrete through the project site. Sediment basin upstream and concrete lining will
limit the amount of sediment accumulation in the new channel.
Cost Estimate:
Total Estimated Cost:[Insert total once confirmed]
(32.402085, -110.972977)
Highlands Wash
W Appalachian St. to
W Matterhorn St.
In partnership with
Status: Active
Last Revised: 12/1/25
Gravel Pit Wash
at
N Pomegranate Dr.
Project Overview
This project addresses stormwater management needs at Gravel Pit Wash near North
Pomegranate Drive. The existing roadside drainage requires improvements to ensure
proper flow control and erosion mitigation.
Proposed Improvements
Curb & Roadside Provisions: Install approximately 220 linear feet of curb and roadside
drainage infrastructure.
Drainage Control: Direct stormwater into a single spillway for more efficient flow
management.
Erosion Mitigation: Construct a drop spillway with a gabion basket to dissipate energy
and reduce erosion.
Grading: Perform approximately 110 linear feet of grading perpendicular to the
roadway to stabilize the channel and improve flow capacity.
Cost Estimate
Federal Funding: $209,019
Town of Oro Valley Contribution: $69,673
Total Estimated Cost: $278,692
(32.401918, -110.980594)
In partnership with
Status: Active
Last Revised: 12/1/25
Project Overview:
The existing west slope of Mutterer’s Wash, with a height ranging from 1.5 to 2.5 feet,
is insufficient to contain stormwater flows during peak events. This limitation poses a
risk of overflow and erosion, particularly during monsoon season.
Proposed Improvements
Hydrologic Assessment: Conduct a detailed evaluation of approximately 590 linear feet
of the wash to determine the required channel capacity enhancements.
Slope Stabilization: Armor the west slope and elevate the east bank by 2.5 feet to
improve containment and reduce erosion.
Infrastructure Enhancements:
•Extend the headwall at the culvert inlet by approximately 45 linear feet.
•Construct a spillway to connect with the existing 36-inch storm drainpipe.
Design Considerations:
•Preserve the existing tree line and avoid disruption to utilities.
•Integrate drainage from the adjacent pedestrian path, which currently
discharges into the wash via six-inch pipes.
Cost Estimate: TBD
(32.392483, -110.964584)
Mutterer's Wash
E El Conquistador Wy.
to W Greenock Dr.
In partnership with
Status: Active
Last Revised: 12/1/25
Carmack Wash
at
N Shadow Mountain Dr.
300 Feet North of
W Spring Valley Dr.
Project Description
The channel downstream of the RCBC has downcutting 30 inches deep at the cutoff
wall. There are concerns 275 feet downstream from the culvert with areas of
significant erosion as evidenced by several feet of exposed tree roots and exposed
utilities. There is an exposed water line crossing the wash. There is a natural gas line
marked in the area that has already been replaced due to previous erosion. There is a
utility pole on the edge of the top of bank. Energy dissipation at the RCBC cutoff wall
drop should alleviate the significant erosion downstream.
Proposed Improvements
Energy dissipation. Infrastructure at the RCBC cutoff wall drop is required to
significantly dissipate energy at this location and downstream to reduce the
occurrence of severe erosion. Gabion baskets/mattress may be required.
Bank protection. The downstream locations utility poles in danger of collapsing
require protection. Gabion baskets or concrete may be required.
Utility replacement.The waterline that is crossing the wash requires replacement at a
greater depth.
Cost Estimate:
Total Estimated Cost:[Insert total once confirmed]
(32.369186, -110.971963)Status: Active
Last Revised: 12/1/25
Shadow Mountain Estates 8
Nanini Wash
at
N Paseo Del
Norte
Project Overview
Potential safety concern with a 5 foot vertical drop 21 inches from the edge of pavement with concrete in the
area. There are two oblong 44 inch wide CMPs, one has the full 28-inches of height clear while the other has
only 22 inches of height clear since the lower portion has been filled with cement. Scour below pipes is 14-18-
inches deep. Scour from the collapsed slope north of the culvert is 123 inches wide by 61 inches deep. The
road is being severely undermined at this location, and there are exposed utility lines in the wash.
Proposed Improvements
Guardrail installation.A guardrail is required long the roadway in this location.
Hydraulic analysis. A hydraulic analysis is required to determine if the culverts are adequately sized. Larger
culverts are likely required.
Headwall installation. A headwall should be installed to prevent further degradation of the slope in this
location. Rock-faced slope paving should extend above and around the headwall and culvert.
Scour protection. A gabion basket can be installed below the culverts if they are to remain. If larger culverts
will be installed, they should outlet at the channel bottom into a riprap splash pad.
Cost Estimate
Total Estimated Cost: $85K±
(32.340946, -110.982974)
Status: Active
Last Revised: 12/1/25
In partnership with