Wallace Group I DEDICATION TO SERVICE
ENGINEERING, HYDRAULIC MODELING & BIOLOGICAL MONITORING FOR
ARROYO GRANDE CREEK WATERWAY MANAGEMENT PROGRAM
City of Salinas
October 2024
Stormwater Master Plan Update
PRESENTED TO CITY OF SALINAS CITY COUNCIL
MARCH 11, 2025
Wallace Group I DEDICATION TO SERVICE
, HYDRAULIC MODELING & BIOLOGICAL MONITORING FOR
ARROYO GRANDE CREEK WATERWAY MANAGEMENT PROGRAM
Overview of the City’s Storm Drain System
Purpose of the Master Plan
Proposed Stormwater Projects
Risks and Impacts
Funding
Questions
PRESENTATION AGENDA
Wallace Group I DEDICATION TO SERVICE
STO
RM DRAIN
SYSTEM
Wallace Group I DEDICATION TO SERVICE
ENGINEERING, HYDRAULIC MODELING & BIOLOGICAL MONITORING FOR
ARROYO GRANDE CREEK WATERWAY MANAGEMENT PROGRAM
Photo Credit: https://www8.honolulu.gov/swq/info-
resources/our-storm-water-system
• Pipes and channels
• Manholes
• Inlets
• Outfalls
Storm Drain Systems
Wallace Group I DEDICATION TO SERVICE
Photo Credit: https://www.vapar.co/manhole-meaning/
Storm Drain Manholes
Wallace Group I DEDICATION TO SERVICE
ENGINEERING, HYDRAULIC MODELING & BIOLOGICAL MONITORING FOR
ARROYO GRANDE CREEK WATERWAY MANAGEMENT PROGRAM
Photo Credit: https://www.centralmastormwater.org/municipalities/pages/municipal-resources Storm Drain Inlets
Wallace Group I DEDICATION TO SERVICE
Photo Credit: https://www.pca.state.mn.us/news-and-stories/ask-the-mpca-the-function-of-storm-drains Storm Drain Inlets
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Municipal Separate Storm Sewer System (MS4)
City of Salinas (MS4)
• Over 6,000 assets
• Over 145 miles of pipes,
culverts, and channels
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Stormwater Discharges
to Local Waterways
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PURPOSE
Of the SWMP
UNDERSTAND THE
CONDITION OF THE
EXISTING SYSTEM
IDENTIFY AND
PRIORITIZE
NECESSARY PROJECTS
Wallace Group I DEDICATION TO SERVICE
ENGINEERING, HYDRAULIC MODELING & BIOLOGICAL MONITORING FOR
ARROYO GRANDE CREEK WATERWAY MANAGEMENT PROGRAM
Understand the System
• TOPO AND
MAPPING
• STAFF
INTERVIEWS
• FIELD REVIEWS
Wallace Group I DEDICATION TO SERVICE
Understand the System
• TOPO AND MAPPING
• STAFF INTERVIEWS
• FIELD REVIEWS
Wallace Group I DEDICATION TO SERVICE
Understand the System
MODELING
• SURFACE RUNOFF
• UNDERGROUND INFRASTRUCTURE
Wallace Group I DEDICATION TO SERVICE
Identify & Prioritize Projects
Priority Ranking
Flood Frequency
Flood Severity
Climate Resiliency
Public Safety
Critical Facilites
Evacuation Routes
High Traffic Roads
Wallace Group I DEDICATION TO SERVICE
PROPOSED PROJECTS
Photo Credit: https://www.thecalifornian.com/story/news/local/2024/10/22/california- water-infrastructure-improvements-new-wells-underway-in-salinas Wallace Group I DEDICATION TO SERVICE
ENGINEERING, HYDRAULIC MODELING & BIOLOGICAL MONITORING FOR
ARROYO GRANDE CREEK WATERWAY MANAGEMENT PROGRAM
Proposed Projects
Project Rankings
High Priority
Medium Priority
Low Priority
Maintenance
Wallace Group I DEDICATION TO SERVICE
High Priority Projects
• 18 Projects
• Known Problem Areas
• Sediment Removal
• New Inlets
• Focused Studies
• 12+ Million
Wallace Group I DEDICATION TO SERVICE
Photo Credit: https://www.thecalifornian.com/story/news/local/2024/10/22/california-water- infrastructure-improvements-new-wells-underway-in-salinas Medium Priority Projects
• 22 Projects
• Pipe Upgrades
• New Inlets
• $200+ Million
Low Priority Projects
• 23 Projects
• Pipe Upgrades
• New Inlets
• $100+ Million
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RISK AND IMPACTS
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Health and Safety
Wallace Group I DEDICATION TO SERVICE
Photo Credits:
https://www.ksbw.com/article/road-closed-outside-salinas-flooding-california https://salinasvalleytribune.com/winter-storm-triggers-evacuations-flooding-in-salinas-valley/ https://www.cityofsalinas.org/Your-Government/Departments/Salinas-Fire-Department Health and Safety
Wallace Group I DEDICATION TO SERVICE
Property Damage
Wallace Group I DEDICATION TO SERVICE
ENGINEERING, HYDRAULIC MODELING & BIOLOGICAL MONITORING FOR
ARROYO GRANDE CREEK WATERWAY MANAGEMENT PROGRAM
Pavement Damage
Wallace Group I DEDICATION TO SERVICE
ENGINEERING, HYDRAULIC MODELING & BIOLOGICAL MONITORING FOR
ARROYO GRANDE CREEK WATERWAY MANAGEMENT PROGRAM
Photo Credit:
LA Times, Ventura County Fire Department
Sinkholes
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ENGINEERING, HYDRAULIC MODELING & BIOLOGICAL MONITORING FOR ARROYO GRANDE CREEK WATERWAY MANAGEMENT PROGRAMDeferred Maintenance Can Contribute to Flooding
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FUNDING
Photo Credit: https://www.thecalifornian.com/story/news/local/2024/10/22/california-water-infrastructure- improvements-new-wells-underway-in-salinas
www.cleanwatersalinas.com
Business as Usual
Service rate:
Minimal proactive
repairs and no
proactive
replacement of
assets
Costs:
Cost is $101M
over 20 years with
no funding gap
Risk:
After 20 years,
1/3 of City assets
will be at very
high risk of failure
(currently 1/10)
www.cleanwatersalinas.com
Proposed Service Rate Increase:
Service rate:
Proactively
replace riskiest
assets, and
increase
maintenance and
repairs of others
Costs:
Cost is $237M
over 20 years,
requiring
additional
revenue of
$6.5M/year
Risk:
After 20 years, no
City assets will be
at very high risk of
failure (currently
1/10)
CBP3 2021- Great opportunity; Leadership change
and lack of SW utility
Urban Greening Grant 2022 - Green street project at
DAC Park; didn’t want multi-benefit
NOAA Climate Resilience Challenge - Looking for
regional partnership; not “coastal” enough
CW SRF - Principal forgiveness stormwater add-on to
currently funded corridor project; Timing challenges
FEMA FMA - Lack of disaster insurance loss claims
Recent Funding
Opportunities Explored
Wallace Group I DEDICATION TO SERVICE
CONCLUSION
Photo Credit:
KION News 46
Data is Power: Map, attribute and model
stormwater system
Focus on multi-benefit project concepts in
DAC areas
Educate and engage city leadership and
peers on the value of better managed
stormwater
Research and understand funding
opportunities and challenges
Work towards a stormwater utility fee
Salinas Strategy
Wallace Group I DEDICATION TO SERVICE
Photo Credit: https://salinascitycenter.com/
Questions?