Agenda packet, special meeting — San Mateo City Council, January 26, 2026

CITY OF SAN MATEO
City Council Special Meeting
January 26, 2026
6:00 PM
City Hall Council Chamber
Entrance is on O’Farrell Street

COUNCIL MEMBERS
Adam Loraine
Nicole Fernandez
Danielle Cwirko-Godycki
Lisa Diaz Nash
Robert Newsom Jr.

AGENDA
THIS MEETING CAN BE ATTENDED IN PERSON OR REMOTE BY JOINING ZOOM – SEE CODES BELOW.

PUBLIC COMMENTS WILL BE ACCEPTED BOTH IN PERSON AND REMOTELY .

SEE END OF AGENDA FOR OPTIONS AND INSTRUCTIONS ON HOW TO PARTICIPATE IN THE MEETING.

To join via Zoom – click here:

January 26, 2026
To join via telephone: (408) 638-0968
Webinar ID: 837 5146 7717 Passcode: 288299

CALL TO ORDER
Roll Call

AB 2449 Requests and Considerations for Meeting Participation by Teleconference due to Just Cause or Emergency Circumstances

STUDY SESSION
The public will have an opportunity to comment during the consideration of this item.

1. Storm Drain Master Plan — Informational Update
Receive an update on the City’s Storm Drain Master Plan efforts and provide feedback.

CEQA: This informational update is not a project subject to CEQA, because it is an organizational or administrative activity that will not result in direct or indirect physical changes in the environment. (CEQA Guidelines Section 15378(b)(5).)

ADJOURNMENT
----------------------------------------------------------------------------------------------------------------------------- AGENDAS:

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PUBLIC COMMENTS/REQUEST TO SPEAK

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Prior to the Meeting
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During the meeting
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Call (408) 638-0968 and enter the conference ID found at the top of the meeting agenda. When the item of interest is open for consideration, select *9 to raise your hand. When called upon, press *6 to unmute, state your name and provide your comments.

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At the meeting complete a “Request to Speak” form. Organized Group and Presentations: Up to five (5) minutes for a group presentation, with as many speakers as can be accommodated within that time allowance. To qualify for a group presentation, all individuals associated with the presentation must be clearly identified and confirmed as in attendance at the meeting. Presentation materials must be submitted to [email protected] one (1) business day in advance of the meeting.

ACCESSIBILITY:

In compliance with the Americans with Disabilities Act to ensure meaningful access for all participants, including those with limited English proficiency, individuals requiring special accommodations or language assistance to participate in this meeting may contact the City Clerk’s Office at (650) 522-7040 or [email protected]. Notification 48 hours prior to the meeting will enable the City to make reasonable arrangements to ensure accessibility to this meeting.

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CITY OF SAN MATEO
Agenda Report
City Hall
330 W. 20th Avenue
San Mateo CA 94403
www.cityofsanmateo.org
Agenda Number: 1 Section Name: STUDY SESSION Account Number: 10-4679 File ID: 26-10816 TO: City Council
FROM: Alex Khojikian, City Manager
PREPARED BY: Public Works Department
MEETING DATE: January 26, 2026
SUBJECT:

Storm Drain Master Plan — Informational Update
RECOMMENDATION:

Receive an update on the City’s Storm Drain Master Plan efforts and provide feedback.

BACKGROUND:

History
The City of San Mateo (City) encompasses seven major artificial and natural drainage areas, including: (1) North Shoreview District; (2) San Mateo Creek; (3) East 3rd Avenue; (4) 16th Avenue Drain; (5) 19th Avenue Drain; (6) Laurel Creek; and (7) direct drainage to Marina Lagoon, see Attachment 1. The latter four drainage areas discharge to Marina Lagoon, a large storage and pumping facility created from Seal Slough.

Major sources of flood risk within the City include: (1) coastal flooding associated with high tides in San Francisco Bay and (2) interior flooding resulting from stormwater runoff during significant storm events. Prior to the most recent New Year’s Eve 2022 storm event, historic storms with documented serious flooding occurred in December 1950, April 1958, January 1982, January 1983, February 1986, and February 1998.

To address stormwater conveyance and flood risk, the City’s first comprehensive Storm Drain Master Plan was published in 1966. This plan provided recommendations for major drainage facilities within the City, while the design of local storm drains was placed under the purview of developers as land was improved within the watershed area. In the decades following publication of the 1966 plan, developers and the City’s Public Works Department made incremental improvements to the storm drain system. However, environmental laws enacted in the late 1980s and early 1990s shifted stormwater management objectives from a sole focus on flood control to also include pollution prevention. Within this evolving regulatory framework, the City developed the most recent Storm Drain Master Plan in 2004.

The 2004 Storm Drain Master Plan included an evaluation of the City’s storm drainage system as a whole, including pipes, channels, and pump stations, as well as recommendations for capital improvements and maintenance. While several recommended projects were constructed, primarily focused on levee improvements and coastal flood risk reduction, the City’s efforts related to storm drain infrastructure upgrades and interior flooding risk were largely limited to maintenance and repair of the existing system due to a lack of dedicated funding.

During the New Year’s Eve 2022 storm event, more than 4.5 inches of precipitation fell over a 12-hour period, representing an approximately 200-year storm event with a 1-in-200 (0.5 %) annual chance of occurrence. As a result, the City’s stormwater conveyance system was overwhelmed, which included overtopping of San Mateo Creek and flooding in multiple neighborhoods. In addition, mechanical failures at the Marina Lagoon Pump Station prevented pumps from

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activating as intended, contributing to additional interior flooding around the Marina Lagoon and in upstream drainage areas.

The New Year’s Eve 2022 storm marked the beginning of an unprecedented series of nine atmospheric rivers and a “bomb cyclone” occurring between late December 2022 and March 2023, which resulted in states of emergency being declared by both the Governor and the President.

Stormwater Fee
Prior to the 2022–2023 storm events, the City was already evaluating funding options to finance flood control capital improvements, including upgrades to the storm drain infrastructure. A draft Stormwater Funding Analysis Report was published in January 2021 and proposed establishing an enterprise fund supported by a user fee. Implementation of the enterprise fund would be subject to voter approval requirements under Proposition 218.

In November 2021, a survey was mailed to property owners to gauge support for a stormwater fee. The survey achieved a

16.6% response rate and indicated neutral support for a $120 per year fee for flood protection and stormwater infrastructure purposes. A follow-up survey mailed in late March 2023 showed increased support, with more than 50% of respondents favoring an average fee of $96 per year for flood protection and stormwater infrastructure purposes.

In November 2023, property owners were sent ballots to vote on the Community Flood and Storm Protection Fee (Storm Fee), with 51.78% of returned ballots supporting adoption of the fee. The City Council formally adopted the Storm Fee on January 16, 2024, and directed levy of the fee beginning in Fiscal Year 2024/25 on County tax rolls. Based on a median per- parcel contribution of $96 per year, the Storm Fee is expected to generate approximately $4 million annually for stormwater maintenance and capital improvements. This new revenue stream has enabled the City to make advancements in strengthening its stormwater program, most notably by initiating the reevaluation and update of the City’s outdated 2004 Stormwater Master Plan and by increasing its preventative maintenance efforts.

Project Initiation and Scope
In January 2024, the City issued a Request for Proposals (RFP) for a Storm Drain Master Plan Update. Two consultants submitted proposals, and Schaaf & Wheeler (S&W) was ultimately selected to perform the Storm Drain Master Plan Update scope.

The full scope of the Storm Drain Master Plan Update (Master Plan Update) was awarded to S&W on June 17, 2024, with the primary objective of developing a prioritized list of stormwater capital improvement projects (CIPs) to extend system serviceability for future generations in San Mateo.

In preparation for developing the prioritized project list, S&W was tasked with conducting a condition assessment of existing infrastructure and available data, developing a stormwater and climate model, and establishing specific criteria for project ranking. These components are discussed in further detail in this staff report.

Condition Assessment and Data Acquisition
As part of the Master Plan Update, S&W reviewed readily available land use, topographic, geologic, geographic, and storm drain system data. These data were used to develop the following:
A Citywide digital elevation model (DEM) utilizing 2017 San Mateo County LiDAR (light detection and ranging) data, 2022 LiDAR data in the vicinity of the Coyote Pump Station, and 2024 Marina Lagoon bathymetric data. The DEM was used to develop hydrologic and hydraulic models.
Topographic models of major storage facilities, including the two dams at the upstream end of Laurel Creek, the regional Bay Meadows detention pond, and the Poplar Pump Station forebay. A geographic information system (GIS) map of the City’s storm drain system, which was used to identify data gaps such as missing pipes and culverts, unknown pipe diameters and rim elevations, and storm drain systems within

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the City of Belmont that discharge into the City’s system.

The physical condition of roughly 30% of the City’s storm drain system was evaluated in the field using a pole-mounted camera. These findings were used to identify potential problem areas where closed-circuit television (CCTV) would be beneficial to further evaluate repair, replacement, and maintenance needs. In addition, critical reaches of corrugated metal pipe (CMP) were identified for additional CCTV inspection, because this pipe material has a greater susceptibility to corrosion, crushing, or failure. 28,000 linear feet of pipe was identified for CCTV inspection, and each CCTV-inspected pipe segment was assigned a structural and operational/maintenance rating.

The condition assessment also included evaluations of nine of the City’s 10 stormwater pump stations through staff interviews and visual observations (the pump station at the 31st Avenue undercrossing was not evaluated due to it being recently constructed). These evaluations assessed existing equipment conditions and operating procedures and informed recommendations for future improvements to system capacity and performance.

Although limited field measurements of the storm drain system were conducted, surveying the entire Citywide system would have been prohibitively time-consuming and costly. To develop a functional stormwater model, reasonable assumptions and engineering judgment were applied to address remaining data gaps.

Model Development and Capacity Evaluation
A rainfall-runoff model was developed for the City to represent the storm drainage pipe system, open channels, ponds and lagoons, and pump stations that provide essential conveyance and storage capacity for stormwater runoff. The modeled existing system includes approximately 8,500 nodes, more than 148 miles of pipes, and 11.2 miles of open channels, including creeks, ditches, and Marina Lagoon.

The model utilizes a range of storm durations and storm events, which are used to estimate runoff and evaluate system performance within the stormwater network. Evaluation of the system performance is based on either a 10- or 100-year level-of-service standard, depending upon the criticality of the stormwater asset. A 10-year storm event has a 10 percent annual probability of occurrence, and a 100-year event has a one percent annual probability of occurrence. Level-of- service standards are used to determine when capital improvement projects (CIPs) may be necessary to correct system capacity deficiencies.

A 10-year storm was used as the level-of-service standard for evaluating the gravity pipe systems and smaller pump stations, consistent with best practices as well as neighboring jurisdictions. Attachment 2 shows the extent of flooding under existing conditions for a 10-year storm event. A 100-year storm event was used as the level-of-service standard for evaluating the Marina Lagoon, creeks, and major pump stations. Other storm events that were evaluated but were not used as a level-of-service standard included the 2- and 25-year storms.

City staff also identified 33 known, recurring stormwater system deficiencies based on field observations and resident reports. The hydraulic models were used to evaluate the causes of these deficiencies and to identify additional areas likely to experience significant flooding during design storm events.

CIP Development
The development of CIPs focused primarily on addressing the most severe and frequently recurring flooding issues identified by City staff and confirmed by the stormwater models. These locations are characterized by documented flooding even during small storms, and model results indicate that high-intensity rainfall during a 10-year event is likely to cause system overflows, creating risks such as property damage, prolonged disruption to traffic and emergency services, and potential threats to life safety. The model results for the design storm were used to evaluate system deficiencies and, in combination with established CIP criteria, to prioritize projects.

Prioritization criteria include system capacity, physical condition, flood reduction potential, risk exposure, proximity and

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connectivity with upstream and downstream projects, operations and maintenance burden, cost, and the need for multi- jurisdictional coordination with other agencies. For pump station projects, additional prioritization factors such as pump station age and remaining life, emergency capability, and operational performance were also considered.

Projects are divided into four different categories: Gravity System Capacity, Creek and Channel Capacity, Condition/Maintenance, and Pump Station Improvements, and are assigned one of four priorities: Low, Medium, High, or Very High. Projects with a “Very High” designation are intended to address urgent flooding issues with the highest risk of erosion or property damage, where repairs or replacement of the existing system are prioritized because the likelihood of failure is high.

Specific projects have been identified that are intended to provide a 10-year minimum level of service throughout the City, with a 100-year level of service for terminal pump stations and major open channels. Attachment 3 shows the full list of prioritized improvements. Attachment 4 maps the proposed improvements for the Gravity System, Creeks and Channels, and Condition/Maintenance, and Pump Station project types.

The complete stormwater CIP program baseline (without considering the impact of climate change) in today‘s dollars totals approximately $233 million, based on industry-standard cost estimating practices, inflation indices, and actual cost and bid data from recent projects. It is noted that this is based on preliminary planning-level cost estimates, and project elements, including location, cost, and timing, are subject to change as the Master Plan Update document is reviewed and refined, and even following the Master Plan Update adoption, as projects are further evaluated and progress to detailed design.

Conveyance capacity and repair project cost estimates include a 30% contingency, 20% administration, and 20% design and engineering allowance. Environmental permitting costs are assumed to be 20–25% of construction costs in cases where permitting beyond a California Environmental Quality Act (CEQA) Negative Declaration is anticipated.

Table 1 shows the breakdown of costs by project type.

Table 1 – Stormwater CIP Program by Project Type
Project Type Number of Projects Estimated Cost (in
Millions)
Gravity System Capacity 79 $52
Creek and Channels Capacity 9 $40
Condition / Maintenance 33 $6
Pump Stations Improvements 16 $135
Total: 137 $233
Creek and channel projects primarily address 100-year capacity deficiencies. At 16th Avenue Channel, the Highway 101 culvert is undersized and will require replacement or additional new parallel culverts. For Laurel Creek, the highest priorities are vegetation management between 39th and 40th Avenues to restore channel capacity and construction pf conveyance improvements. Along San Mateo Creek, recommended projects include enlarging the Crystal Springs Road culvert and improving downstream levees to address tidal-reach capacity constraints.

Table 2 further breaks down the overall cost across all project types according to priority, ranging from “Low” to “Very High.” The last column in the table denotes the total cost if the Marina Lagoon Pump Station is removed from the project totals, the details of which are described after the table.

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Table 2 – Stormwater CIP Program by Project Priority

Priority Number of
Projects
Estimated Cost
(in Millions)
Estimated Cost
without Marina
Lagoon Pump
Station (in Millions)
Very High 11 $160 $39
High 33 $27 $27
Medium 35 $22 $22
Low 58 $24 $24
Total: 137 $233 $112
Pump station improvements for the Marina Lagoon Pump Station are estimated at more than $123 million (short-term: $2 million; long-term: $121 million), representing over 52% of the total CIP program. While the cost is significant, the Marina Lagoon Pump Station is an important asset for storm flood protection, as it captures approximately two-thirds of the City’s drainage prior to discharge to the San Francisco Bay.

Long-term improvements include building a new pump station separate from the existing one that can operate during both low lagoon levels and high San Francisco Bay levels. Once the new station is in service, the existing Marina Lagoon Pump Station would be rebuilt or upgraded to provide pumping capacity similar to what exists today, using modern equipment and improved features. Together, the new pump station and upgraded facility will provide pumping capacity for the range of design storms anticipated (low lagoon levels, high tide, and sea level rise) and will have an extended useful life.

Given the size and complexity of the Marina Lagoon pump station, as well as the limitations of current funding resources, it is recommended that this project be planned and managed as a standalone objective. Treating it independently allows for focused design, budgeting, and implementation, without being constrained or delayed by other concurrent projects. This approach ensures that the pump station can meet future operational requirements efficiently while maximizing the use of available funds for other priority projects.

It is noted that dredging of the Marina Lagoon is not included in the Stormwater CIP Program tables above, as this was separately evaluated by a 2018 Marina Lagoon Preliminary Dredging Assessment by Moffat & Nichol. Estimated costs varied significantly between $42.5 million and $84.5 million, depending upon how the dredged material would be disposed of.

The 2018 Marina Lagoon sedimentation assessment evaluated changes in lagoon bathymetry relative to a 1996 survey at both winter and summer operating levels. For this analysis, updated bathymetric data collected as part of the Stormwater Master Plan Update scope was compared with the 1996 baseline. The comparison indicates that the majority of sediment accumulation has occurred below the lagoon’s usable flood storage elevation during storm events, with limited encroachment into the portion of the lagoon relied upon for flood management. Based on observed sedimentation rates and current distribution, continued accumulation at similar levels would result in an estimated approximately 1 percent reduction in usable flood storage over a 10-year period.

While sedimentation patterns may evolve over time, current data does not indicate an immediate risk to the lagoon’s usable flood storage or to the operational performance of the Marina Lagoon Pump Station. Staff will continue to monitor sediment conditions as part of ongoing system evaluation.

Notwithstanding the overall limited impact on usable flood storage, sediment accumulation is more pronounced in the southern portion of the lagoon, where it may affect conveyance capacity from Laurel Creek. Targeted dredging in this area may be appropriate to maintain hydraulic connectivity and preserve localized flood management performance during

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larger storm events. In summer 2026, the City will be undertaking spot dredging efforts of the Marina Lagoon at the Leslie Creek and Borel Creek inlets to the Marina Lagoon to restore hydraulic connectivity.

Evaluation of Climate Change Impacts
Climate change considerations for stormwater improvements in San Mateo fall into two distinct but interconnected categories: increased precipitation resulting from changing climate patterns and sea level rise affecting coastal reaches.

These considerations are reviewed as part of the Stormwater Master Plan Update to help ensure that proposed projects remain resilient and adaptable.

The storm drain model evaluates two climate change scenarios:
2050 Scenario: 10-year storm depth increased uniformly by 10%, with 100-year tide elevated by 0.8 ft 2100 Scenario: 10-year storm depth increased uniformly by 30%, with 100-year tide elevated by 3.1 ft The City’s stormwater system model uses a combined analysis that accounts for potential climate change impacts. This includes the Environmental Protection Agency’s Stormwater Management Model Climate Adjustment Tool, which provides location-specific factors for 2035 and 2060 based on global climate models, and CalAdapt, which offers additional estimates of future climate impacts in California, including extreme precipitation events.

Sea level rise estimates are consistent with the California Ocean Protection Council’s (OPC’s) “Intermediate” sea level rise scenarios. A high-level shoreline feature susceptibility evaluation was additionally performed using the OPC’s “High” sea level rise scenario, which corresponds to 1.2 ft and 6.6 ft of sea level rise by 2050 and 2100, respectively.

The existing conditions model has been run for the 2050 climate change conditions, while the CIP model, which assumes recommended projects are completed, was run for both the 2050 and 2100 climate change conditions. In other words, the climate change model was not used to increase the size of drainage network elements for the baseline recommended projects. Instead, it was applied to highlight locations where the Capital Improvement Program (CIP) may require additional climate change considerations during design and to identify areas where future projects may be needed as the CIP is updated. The model identifies several locations at risk for additional, significant flooding due to the impacts of climate change.

As an order-of-magnitude estimate, incorporating climate change considerations for interior flooding projects could add approximately $8 million in project value to modified existing projects and $26 million in construction of entirely new projects, with a total cost of $34 million. New projects include improvements and expansions of existing culverts and crossings at the 16th Avenue Channel and Laurel Creek, upgrades to levees along San Mateo Creek, and a variety of gravity system capacity enhancements through the installation of new piping in several areas of San Mateo, specifically along 9th Avenue, 19th Avenue, Dore Avenue, and Pacific Avenue. Table 3 shows the combined total CIP cost for existing and climate change conditions.

Table 3 – Stormwater CIP Program by Project Type with Climate Change Existing Condition Climate Change
Project Type Number of
Projects
Estimated
Cost (in
Millions)
Number of
Projects
Estimated
Cost (in
Millions)
Total
Estimated
Cost (in
Millions)
Gravity System Capacity 79 $52 8 $12 $64
Creek and Channels Capacity 9 $40 11 $21 $61
Condition / Maintenance 33 $6 0 $0 $6
Pump Stations Improvements 16 $135 1 $1 $136
Total: 137 $233 20 $34 $267

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Adaptation Strategies
The full scope of a sea level rise vulnerability assessment, including evaluation of the City’s vulnerability to rising shallow groundwater or development of comprehensive coastal protection measures, including erosion control, shoreline armoring, flood walls, or levees, are beyond the scope of the Stormwater Master Plan Update. However, the City is separately developing a Climate Adaptation Plan which meets the San Francisco Bay Conservation and Development Commission (BCDC) Regional Shoreline Adaptation Plan (RSAP) Guidelines. This Climate Adaptation Plan will further evaluate the City’s vulnerability to climate change and will help to identify adaptation strategies. The findings from the Master Plan Update will be used to inform the Climate Adaptation Plan.

In addition, the City is a member jurisdiction of the San Mateo County Flood and Sea Level Rise Resiliency District (OneShoreline), established in 2020 to protect residents and businesses from the impacts of sea level rise. OneShoreline is currently evaluating projects that would provide resilient mitigation measures to address sea level rise. Currently, OneShoreline is developing countywide guidance to support climate-resilient public infrastructure planning and design.

Key Master Plan Findings

1. Gravity Pipe Condition Improvement Projects
The CCTV inspections revealed that while most of the observed pipes were found to be in good condition, approximately 28% of the inspected system is rated in poor structural condition (rating 4–5) and will generally require immediate attention, and in most cases, replacement. If the CCTV inspections are taken as a representative sample, the City’s metal pipes, which make up approximately 2-3% of the system, are beginning to corrode and fail with age, and should be prioritized for repair or replacement. Approximately 61% of the City’s storm drain system has an unknown material type, so the actual length of metal pipes is unknown. Additional field verification is necessary to understand the full scope of system repair and replacement needs.

2. Marina Lagoon Pump Station Improvements
In recent years, staff has implemented maintenance improvements at the Marina Lagoon Pump Station to help extend its useful life. While the pump station’s reliability can be sustained for additional years through routine maintenance, the facility is nearing the end of its service life and continues to experience periodic equipment failures, with several major components having required repair or replacement. In addition, though the Marina Lagoon Pump Station can accommodate a 100-year design storm, its capacity is not sufficient to address 100-year tide levels or 2050 and 2100 sea level rise scenarios.

The City is currently undertaking, separate from the Master Plan Update, a physical modeling assessment for Marina Lagoon which will help to evaluate performance at low lagoon levels.

3. Pump Station Capacity
Most pump stations currently meet their assigned design storm criteria. When considering climate change impacts, the existing pump stations remain sufficient to handle increased precipitation only if the associated pump station priority projects are fully implemented, including the long-term upgrades to the Marina Lagoon Pump Station, which will add two additional pumps to increase capacity. Furthermore, an additional tide gate and pump station may need to be constructed at the mouth of San Mateo Creek to control tidal influences.

4. Existing FEMA Flood Zones
There are still isolated areas within the City of San Mateo where properties fall within FEMA-designated special hazard flood zones.
a.16th Ave/Palm – Updates to the storm drain system, along with refinements in the hydraulic model, now preliminarily show this area as being outside the flood zone. No CIP projects appear needed to resolve this mapping issue, and ultimately staff would work with FEMA to update the official maps. b.3rd Avenue/Norfolk – Project estimates are approximately $1,200,000

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c.Hillsdale/McLellan – Project estimates are approximately $11,200,000

5. Climate Change Effects
Focusing on projects within the City’s direct control, the climate change-related impacts for San Mateo are generally smaller in scale compared to overall system stormwater deficiencies. Estimated costs for climate change resiliency projects are approximately $33 million (not including Marina Lagoon Pump Station upgrades), compared with roughly $232 million for full non-climate system improvements. With careful planning and pursuit of outside funding opportunities, the City can make meaningful improvements to enhance climate change resilience.

However, there are climate change issues beyond the intended scope of this Stormwater Master Plan update that will require further evaluation and analysis. Because climate change impacts occur at a regional scale and do not align with individual city boundaries, multi-agency coordination is necessary to adequately evaluate impacts and identify appropriate improvements. Among the regional-level challenges, the two most prominent relate to shoreline protection and channel protection along San Mateo Creek. Both issues would require large-scale system improvements, potentially in the form of levee reconstruction along coastal reaches, low-lying interior areas, and levees along the entire stretch of San Mateo Creek.

Given the scale of these potential improvements, and the limited scope of the Stormwater Master Plan update, which is intended to focus on more localized improvements within available resource, further multi-agency coordination and study will be necessary to address these issues effectively.

6. Operations and Maintenance Efforts
Open channel maintenance is critical to restoring and maintaining capacity for outlets and open channels. By separate contract, the City is pursuing a multi-agency Citywide Creek Maintenance Permit to facilitate this maintenance work. Open channel maintenance priorities include:
a. Replacing broken flap gates
b. Vegetation management at critical creek sections, such as 16 th Avenue Channel and Laurel Creek between 29th and 40th Avenue
c. Sediment management, particularly where sedimentation may begin to impact outfalls d. Keeping debris racks clean and in a state of good repair Funding:

The Storm Fee generates approximately $4.0 million in annual revenue for stormwater-related activities. Currently, the City has $600,000 budgeted in annual operation and maintenance costs, but this is forecasted to increase with increased vegetation and overall drainage system management needs. On an annual basis, the remainder would be available for potential capital improvement projects.

Given the scale of improvements identified in the Master Plan Update, the current stormwater fee is insufficient to fully fund the recommended projects within the proposed implementation timeframe, which advises for completion of “Very High” priority projects within 10 years. This funding gap is driven primarily by the significant capital investment required for the long-term investment in upgrading the Marina Lagoon Pump Station, which represents a cost of approximately $125 million.

Excluding the Marina Lagoon Pump Station improvements, the remaining 136 projects identified in the Master Plan represent a more manageable funding obligation. For example, without the Marina Lagoon Pump Station project, the “Very High” priority projects, recommended for completion within 10 years, represent approximately $39.1 million in total funding requirements. Staff will explore the use of existing stormwater fee revenues to support bonding, similar to the approach used for the Smooth Streets Program. This financing strategy would allow the City to leverage a larger pool of capital funding to advance the design and construction of critical stormwater improvement projects identified as “Very High” priority. A portion of the existing stormwater fee revenues would then need to be dedicated to debt service payments associated with the bonds. Staff will also explore opportunities for outside funding, such as the Federal

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Emergency Management Agency (FEMA) Hazard Mitigation Grant Program (HMGP) and the FEMA Building Resilient Infrastructure and Communities (BRIC) Program, in addition to other applicable State infrastructure grant programs.

In the near term, staff recommends advancing the design and construction of certain “Very High” priority projects using available stormwater revenues. Staff plans to move forward with incorporating funds for design of an upgraded 42nd Avenue Pump Station in the upcoming Capital Improvement Program, which ranks third on the project prioritization list, following behind the Marina Lagoon Pump Station Improvements. Staff will also evaluate additional Very High priority stormwater projects that can be advanced within existing budget resources in the upcoming Capital Improvement Program.

Public Engagement
In December 2025, during meetings with the Marina Lagoon Ad Hoc Committee and as part of the annual Wet Weather Update presented to the City Council, staff highlighted ongoing community outreach efforts associated with the Stormwater Master Plan. As part of these efforts, staff has developed an interactive reporting map tool for public use. The mapping tool provides users with the ability to report past flooding events in and around their neighborhoods and citywide. It also allows users to upload photos and short videos of rainfall events. This tool is not intended for reporting flood emergencies.

The data and information uploaded by community members allow the design team to examine past flooding events and validate the storm model for accuracy. Furthermore, the tool can provide crucial information about flooding areas that are not captured in the stormwater model, which may indicate a need for, or an opportunity to explore maintenance improvements that were previously unknown.

Staff anticipates releasing the tool by the end of January and plan to keep it live for several months in support of the Master Plan Update. Staff will consider the option of keeping the tool live beyond this period, to be used on an ongoing basis.

The Stormwater Master Plan draft is anticipated to be available for public review and comment in late February.

Community feedback is an important part of the planning process, and residents are encouraged to provide public comments to help inform final refinements and ensure the plan reflects local priorities and concerns.

Public Works staff will host two community meetings in Spring 2026 to present and discuss the draft updated Stormwater Master Plan. These meetings are intended to provide community members with an opportunity to learn more about the City’s stormwater system, understand planned improvements and priorities, and ask questions directly to City staff.

Community input will help inform implementation of future stormwater projects and programs.

Feedback Received from S&I Commission
Commissioners generally agreed the SDMP addresses a core City responsibility and valued having a clear project list to help the public understand how funds are used. Large, high-cost projects remain the most challenging and will require a combination of incremental local funding and state/federal assistance, with support for considering bonding to address needs sooner and planning for future rainfall impacts.

There was broad support for continuing, and in many cases, increasing investment in addressing nuisance flooding, noting it directly affects daily quality of life and public confidence in the City. Several commissioners emphasized prioritizing high- visibility and high-use areas (major corridors, schools, parks) and cautioned against the term “nuisance,” which understates public experience, though some noted the need to balance this with other priorities. (Going forward, staff will rebrand the term “nuisance” into “localized ponding”)
Commissioners supported having private development contribute a fair share toward stormwater solutions. Questions focused on prioritization criteria, inspection assumptions, and Marina Lagoon infrastructure and sediment management, with recognition that near-term rehabilitation can extend service life while longer-term projects are planned. Finally, some Commissioners expressed interest in expanding public engagement beyond the proposed two public meetings to build

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trust and support for future investments.

Feedback Requested from Council
No formal Council action is needed on this item, but feedback for the following items is requested:

1. Feedback on Storm Drain Prioritized Capital Improvement Program Prioritization Plan and Cost Estimates Attachment 3 of this Report includes a detailed prioritized list of projects and corresponding estimates, does Council have any questions or feedback regarding the prioritization of projects?

2. Funding for Very High Priority Projects
Very High priority projects, recommended for completion within 10 years, represent approximately $39.1 million in total funding requirements. Staff is planning to explore the use of annual stormwater fee revenues to support bonding for these projects, similar to the approach used for the City’s Smooth Streets Program.

Staff is seeking Council feedback on this approach.

3. Localized Ponding Requests
Staff routinely receives requests related to ponding or nuisance flooding throughout the City. For discussion purposes, nuisance flooding is classified as flooding with minimal depth during an average storm or design storm, typically less than 6 inches. These flooding events are usually confined to the gutter area of the street, do not traverse sidewalks, and do not result in flooding onto private property. Such ponding areas are typically caused by insufficient drainage due to either inadequate storm drain infrastructure or variations in street grade that lead to water retention.

Staff has historically addressed these requests on a case-by-case basis, with repair costs varying depending on the street and project location. Under the proposed Master Plan, these types of projects would generally fall into the low to potentially medium priority category. While the ma focus of the Stormwater Master Plan update is to develop a prioritized list of projects—with “Very High” priority projects receiving primary attention, staff recognizes that this approach may leave some areas unaddressed while major improvements are underway.

Currently, staff has been budgeting approximately $250,000 per year to address minor storm drain improvements.

This funding would be used to address projects that would otherwise rank lower on the priority list, while also reflecting the maximum level of work staff can reasonably manage within a given annual funding allocation.

Staff recommends continuing to allocate a relatively small portion of the stormwater fee annually to address minor ponding-related projects and seeking feedback from the Council.

4. Private Development Impacts and Expansion of Required Improvements The Master Plan update provides the City an opportunity to guide changes in how private development addresses stormwater improvements on private property sites to address previously uncontrolled impacts to the City’s storm system. Staff plans to evaluate what opportunities exist to better manage stormwater runoff and address future climate impacts in coordination with private development projects.

Staff is seeking Council feedback on this approach.

Next Steps:

1. Complete internal review and finalize the draft Master Plan

2. Release the draft Master Plan for Commission/Council/public review in February 2026

3. Community Engagement in Spring 2026 (planning for two community meetings)

4. Return to the Sustainability and Infrastructure Commission and City Council with final draft for concurrence

5. Target formal Council adoption by June 2026

6. Incorporate funding for planning/design for a subset of “Very High” priority projects in FY 2026–27 Capital

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CITY OF SAN MATEO
6 1
7 7
Improvement Program

7. Continue evaluating funding/financing options for identified capital improvements BUDGET IMPACT:

There is no budget impact associated with this informational update. Any resulting stormwater capital improvements identified from the prioritization list will be programmed into the annual budget process on a project-specific basis at the time of planning, design, and eventual construction.

ENVIRONMENTAL DETERMINATION:

This informational update is not a project subject to CEQA, because it is an organizational or administrative activity that will not result in direct or indirect physical changes in the environment. (CEQA Guidelines Section 15378(b)(5).)

NOTICE PROVIDED
All meeting noticing requirements were met.

ATTACHMENTS
Att 1 – City of San Mateo Watershed Map
Att 2 – 10-year Storm, 2D Maximum Depth Result from Existing Conditions Att 3 – Prioritized Capital Improvement Project Cost Estimate Summary Att 4 – Prioritized Capital Improvement Project Map

STAFF CONTACT
Jimmy Vo, Senior Engineer
[email protected]
(650) 522-7319

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Attachment 1 - City of San Mateo Watersheds
City of San Mateo Storm Drain Master Plan January 2026
$
0 1,600 3,200 Feet
Coyote-Poplar
Laurel Creek
16th Ave
19th Ave
Marina
Lagoon
(Direct)
San Mateo
Creek

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Attachment 2 - 10-year Existing Condition Model Result
City of San Mateo Storm Drain Master Plan January 2026
$
0 1,200 2,400 Feet
City Boundaries
10yr Max Depth (ft)
Value
< 0.1 (Not Shown)

0.1 - 0.2

0.2 - 0.5

0.5 - 1
1 - 2
> 2

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Att 3 – Prioritized Capital Improvement Project Cost Estimate Summary Priority Project Type
Normalized
Score
Length
(LF)
Approx.

Cost
Very High Marina Lagoon Short-Term Pump Stations 88 -- $1,930,000 Very High Marina Lagoon Long-Term Pump Stations 82 -- $120,740,000 Very High 42nd Avenue Long-Term Pump Stations 70 -- $2,280,000 Very High Laurel Cr - Curtiss Bypass Creeks 67 1,560 $6,350,000 Very High 42nd Avenue Short-Term Pump Stations 66 -- $960,000 Very High 16th Ave Channel -Highway 101 Creeks 63 220 $23,400,000 Very High Grant at Sunnybrae Gravity System 58 301 $430,000 Very High Newbridge Gravity System 58 1,772 $2,100,000
Very High 42nd Ave Underpass Gravity System 56 195 $230,000 Very High Bettina-Kingridge (RR) Repair/Replacement 50 1,118 $898,000 Very High E Laurel Cr - Laurelwood Culvert Creeks 55 175 $570,000 High Norton St Ditch Gravity System 48 2,893 $4,050,000 High Hillsdale Short-Term Pump Stations 48 -- $960,000
High Carlisle Gravity System 47 1,660 $1,960,000
High E Laurel Creek Culvert Inlet Gravity System 47 10 $550,000 High Hillsdale Long-Term Pump Stations 45 -- $1,140,000 High Newbridge Upstream Gravity System 44 2,196 $2,320,000 High Saratoga (RR) Repair/Replacement 44 1,006 $424,000 High San Mateo Cr - Levees, Upstream Creeks 43 1,700 $1,150,000 High Laurel Cr - RR Xing Creeks 43 140 $4,830,000
High Bellevue-Claremont Gravity System 42 950 $660,000
High Monte Diablo (RR) Repair/Replacement 41 654 $396,000 High El Camino Real at Barneson Gravity System 41 90 $610,000 High 3rd & Detroit Short-Term Pump Stations 38 -- $1,150,000 High Grant-Birch Gravity System 38 746 $800,000
High Ocean View (RR) Repair/Replacement 37 549 $512,000 High San Miguel (RR) Repair/Replacement 37 771 $223,000 High Cupertino (RR) Repair/Replacement 37 984 $535,000
High Pasadena Repair (RR) Repair/Replacement 36 437 $85,000 High Oak Valley (RR) Repair/Replacement 35 442 $121,000 High Coyote Short-Term Pump Stations 35 -- $700,000
High Dakota Gravity System 35 21 1 $220,000
High Palm (RR) Repair/Replacement 34 358 $64,000
High Fallon (RR) Repair/Replacement 34 408 $271,000
High Almaden (RR) Repair/Replacement 33 303 $196,000
High 42nd-Kingridge (RR) Repair/Replacement 32 276 $182,000 High Fairfax (RR) Repair/Replacement 32 720 $1 16,000
High Idaho Gravity System 32 1,327 $940,000
High S Delaware at 10th Gravity System 32 1,551 $1,420,000 High Viewridge (RR) Repair/Replacement 31 230 $30,000
High Glendora (RR) Repair/Replacement 31 261 $172,000
High David St (RR) Repair/Replacement 31 315 $160,000
High Parrot-CSM (RR) Repair/Replacement 30 207 $166,000

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Att 3 – Prioritized Capital Improvement Project Cost Estimate Summary Priority Project Type
Normalized
Score
Length
(LF)
Approx.

Cost
High Poplar Short-Term Pump Stations 30 -- $300,000
Medium Santa Clara (RR) Repair/Replacement 29 484 $256,000 Medium Parrot (RR) Repair/Replacement 29 233 $134,000
Medium Parkside (RR) Repair/Replacement 22 350 $148,000 Medium Polhemus (RR) Repair/Replacement 28 129 $134,000 Medium Ellsworth Gravity System 28 139 $1,010,000
Medium Juniper to 27th Ave Gravity System 28 615 $1,440,000 Medium Fathom Drive Short-Term Pump Stations 27 1,436 $740,000 Medium Mason at Bedford Cr (RR) Repair/Replacement 26 -- $76,000 Medium Edinburgh (RR) Repair/Replacement 25 20 $20,000
Medium Grant Gravity System 25 270 $1,280,000
Medium Amphlett 2 Gravity System 25 2,026 $360,000
Medium 11th-Claremont Gravity System 25 618 $850,000
Medium 40th Gravity System 24 1,366 $220,000
Medium 9th at Laurel Gravity System 24 310 $240,000
Medium 3rd & Detroit Long-Term Pump Stations 24 409 $2,730,000 Medium 9th (Bubble Conn) Gravity System 23 -- $850,000
Medium West Poplar Gravity System 23 1,571 $400,000
Medium E Laurel Cr - Channel Cap.

It
Creeks 23 777 $1,160,000
Medium Edison-31st Gravity System 22 330 $190,000
Medium Quebec-Dolan Gravity System 22 747 $390,000
Medium Newlands-42nd (RR) Repair/Replacement 21 282 $186,000 Medium Edinburgh Gravity System 21 649 $760,000
Medium King Gravity System 21 476 $490,000
Medium 17th Ave Gravity System 21 977 $690,000
Medium 3rd Ave at San Mateo (Bubble) Gravity System 21 695 $360,000 Medium Hobart Gravity System 21 1,1 15 $910,000
Medium Hacienda Gravity System 21 1,286 $1,210,000
Medium Avila-Maple Gravity System 21 235 $220,000
Medium B Street Gravity System 21 395 $240,000
Medium Laurie Meadows Gravity System 20 1,350 $1,240,000 Medium Monte Diablo Gravity System 20 1,251 $1,470,000
Medium Casanova Short-Term Pump Stations 20 -- $180,000 Medium Sunnybrae Gravity System 20 458 $250,000
Medium 16th Avenue Long-Term Pump Stations 20 -- $440,000 Medium 16th Avenue Short-Term Pump Stations 20 -- $530,000 Low Hillsdale Frontage Gravity System 19 1,552 $1,950,000 Low Countryside (RR) Repair/Replacement 18 182 $1 12,000 Low Jasmine Lateral Gravity System 18 440 $340,000
Low Shoreview Gravity System 18 906 $640,000
Low Birch Bubble Gravity System 18 493 $220,000
Low 31st-Hillsdale Frontage Gravity System 18 279 $250,000 Low Maple Gravity System 18 715 $520,000

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Att 3 – Prioritized Capital Improvement Project Cost Estimate Summary Priority Project Type
Normalized
Score
Length
(LF)
Approx.

Cost
Low Peninsula (RR) Repair/Replacement 17 69 $66,000
Low Quebec (RR) Repair/Replacement 17 120 $84,000
Low Avila Gravity System 17 1,530 $1,330,000
Low 9th at RR Gravity System 17 236 $230,000
Low W 39th (Bubble Conn) Gravity System 17 798 $480,000 Low Monte Diablo 2 Gravity System 17 1,844 $1,360,000
Low Monte Diablo (Bubble) Gravity System 17 124 $80,000 Low 40th at Casanova-Branson Gravity System 16 618 $500,000 Low B Street (Bubble) Gravity System 16 772 $440,000
Low Mission-Capistrano (Bubble Conn) Gravity System 16 791 $400,000 Low W 39th Main Gravity System 16 803 $920,000
Low Santa Inez (Bubble Up) Gravity System 16 309 $150,000 Low 7th (Bubble Conn) Gravity System 16 292 $150,000
Low Isabelle-30th (Bubble) Gravity System 16 218 $130,000 Low San Mateo Cr - Levees, Tidal Creeks 16 1,260 $710,000 Low 40th (RR) Repair/Replacement 15 28 $20,000
Low Patricia (RR) Repair/Replacement 15 12 $36,000
Low 42nd at Edison Gravity System 15 63 $90,000
Low San Mateo Cr - Crystal Springs Rd
Cl t
Creeks 15 60 $940,000
Low Leslie St Gravity System 14 381 $270,000
Low Warren-Clark Gravity System 14 1,033 $820,000
Low Edison-27th (w/Flap Gate) Gravity System 14 754 $440,000 Low 31st at Hillsdale Park Gravity System 14 474 $370,000 Low Midvale (Bubble Conn) Gravity System 14 103 $70,000 Low Hacienda (Bubble Conn) Gravity System 14 535 $300,000 Low 42nd Ave (RR) Repair/Replacement 13 651 $76,000
Low Trollman Gravity System 13 50 $330,000
Low Norfolk at Susan Ct Gravity System 12 617 $380,000
Low Donner to Colegrove Gravity System 12 504 $490,000
Low S Norfolk at 16th Channel Gravity System 12 822 $770,000 Low West 3rd-Parrot Gravity System 12 41 1 $500,000
Low ECR at Poplar Gravity System 12 657 $230,000
Low Flores-22nd Gravity System 12 251 $1,260,000
Low Flores-Edison (Bubble) Gravity System 11 981 $400,000 Low 20th Ave Gravity System 11 760 $230,000
Low Baldwin Gravity System 11 594 $210,000
Low Kehoe at 16th Channel Gravity System 11 321 $170,000 Low Amphlett 1 Gravity System 11 158 $270,000
Low Indian Gravity System 10 527 $390,000
Low 5th Ave Gravity System 10 629 $250,000
Low 30th-Edison Gravity System 10 284 $420,000
Low Laurel Cr - Laurel Creek Rd
Cl t
Creeks 10 383 $760,000
Low Lodi-Kehoe Gravity System 8 525 $550,000

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Att 3 – Prioritized Capital Improvement Project Cost Estimate Summary Priority Project Type
Normalized
Score
Length
(LF)
Approx.

Cost
Low El Camino South of Lodato Gravity System 8 395 $470,000 Low 10th-Idaho Gravity System 8 670 $470,000
Low ECR Beresford Lateral Gravity System 8 69 $120,000
Low Casanova Long-Term Pump Stations 5 -- $105,000
Low Shoreview (RR) Repair/Replacement 2 136 $29,000
Low Alderwood (RR) Repair/Replacement 1 63 $71,000
Low Woodberry (RR) Repair/Replacement 1 83 $26,000
Low Fathom Drive Long-Term Pump Stations 0 -- $70,000
Total: 76,076 $232,570,000

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Attachment 4 - Prioritized CIP Projects (All Types)
City of San Mateo Storm Drain Master Plan January 2026
$
0 1,250 2,500 Feet
[Ú
[Ú
[Ú
[Ú
[Ú
[Ú
[Ú
42nd Ave
Hillsdale
Casanova
Marina Lagoon
Detroit
Poplar
Coyote Pt
Modeled Pipe
City Boundaries
CIP Pipe
Priority (Pipe System)
Very High
High
Medium
Low
CIP (New Inlets)
Priority
Medium (Inlet)
Pump Station CIP
Priority (PS)
[Ú Very High
[Ú High
[Ú Medium
Creek CIP
Priority (Creek)
Very High
Medium
Low
Levee CIP
Priority (Levee)
Very High
High
Medium
Low

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Stormwater Master
Plan Update
City of San Mateo - City Council
January 26, 2026
Public Works Department – Jimmy Vo, PE
Schaaf and Wheeler – Dan Schaaf, PE

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Council Feedback
Staff requests feedback on the following items:
• General comments on project prioritization and cost estimates • Funding strategies for “Very High” projects ($39.1 M) and support for using stormwater fee revenues for bonding
• Setting aside limited annual funding for minor stormwater projects outside the Stormwater Master Plan priorities
• Reviewing private development stormwater management to reduce City’s system impacts and address future climate conditions

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Presentation Outline
• Context for Stormwater Planning
• Master Plan Update Approach
• Technical Analysis
• Capital Improvement Program Summary
• Key Findings
• Funding Approach
• Public Engagement
• Council Feedback and Next Steps

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• Exposure to flooding risks
due to aging infrastructure
• Recent storms highlighted
system vulnerabilities
• Over 20 years since last
Stormwater Master Plan
Update
• Stormwater Fee supports
long-term planning
Planning Context

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LiDAR Aerial Survey
• Reassess stormwater system
condition and capacity
• Identify system constraints
and deficiencies
• Develop a prioritized capital
improvement framework
Purpose of Master
Plan Update

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Project Overview
• Holistic Study of Drainage
Infrastructure
• Condition
• Capacity
• Reliability
• Climate Impacts
• Capital Improvements
• Design/Fund/Build
• Resilience/Adaptation

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Condition Assessment
Pump Stations:
• Site visits of 9 pump stations
• Data collection: capacity,
condition, and station layout
• Feedback from O&M staff
Conveyance System
• 11,000 LF CCTV
Ranking Structural O&M
1 2% 4%
2 14% 41%
3 18% 19%
4 27% 19%
5 38% 17%

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System Model
• The City has ~150 miles of
pipes and drainage ditches, and
~15 miles of significant
channels (including Marina
Lagoon)
• Eight pump stations perform a
crucial function in handling
stormwater
• There are three dams (Marina
Lagoon + two Laurel)

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System Model
• Example: Sunnybrae
• Existing conditions model
mirrors actual drainage
issues
• CIPs developed
iteratively:
• Try upsizing pipe or adding
new pipe Run model
• Adjust or upsize/add
additional pipe
10-year storm:

Ø 10” max depth
Ø Water in street
for >6 hours

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Capacity Criteria
• “Design Storm”-Based
• 10-year Storm (10% Annual
Chance)
• Closed conduit systems
• Smaller pump stations
• 100-year Storm (1% Annual
Chance)
• Open Channels
• Larger, terminal pump stations
(Marina Lagoon, Coyote, Poplar)

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Pipe System Capacity
• Existing systems (pipes, ditches, creeks) modeled for various storms
Animated Depth for 10-year Storm, Existing Conditions
(Around San Mateo Creek)

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Capital
Improvement
Program (CIP)• Prioritized based on:
• Severity and frequency of
flooding
• Properties impacted
• Pre-requisites (Are other
projects required first)
• Safety issues
• O&M Burden
• Within Equity Priority Area
• Overlapping or Near other
CIP Projects
• Cost
• Factors are not equally
weighted

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10-year Storm Side-by-Side
> 1 ft
Existing With CIP
10-year storm:

Ø 10” depth
Ø Water in street
for ~6 hours

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Climate Change Predictions
• Precipitation: EPA SWMM-CAT and CalAdapt
• Increases in 72-hour Storm Precipitation:
• Sea Levels: Ocean Protection Council
• Increases in Extreme Tide Levels:

Storm 2050 2100
10-year +10% +30%
100-year +8% +20%
2050 2100
Increase: +0.8 ft +3.1 ft

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With CIP +
Climate
Change
10-year storm:

Ø 3” depth
Ø Water in street
for ~1-2 hours
Impact on Pipe Systems (2050)
> 1 ft
Existing
10-year storm:

Ø 10” depth
Ø Water in street
for ~6 hours
In most cases, recommended
CIPs provide an acceptable
degree of resilience against
climate change impacts

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Summary
Work Completed
• Full suite of HEC-HMS, HEC-
RAS, and MIKE+ models have
been developed
• CIP scenarios are complete
• Climate Change has been
incorporated into the analysis,
with cost impact estimated
Next Steps
• Finalize CIP prioritization and
cost estimates
• Preliminary designs for the
highest priority projects
• Work with the City to evaluate
funding strategies

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Key Findings

1. CCTV inspections show most pipes are in good condition, but additional field verification may be necessary to understand the full scope of system repair and replacement needs.

2. Although recent maintenance has extended the Marina Lagoon Pump Station’s life, it is nearing the end of its service life with insufficient capacity for future tide and sea level rise conditions.

3. Most pump stations meet current design standards, but accommodating future climate impacts will require full implementation of priority upgrades, including added pumps at Marina Lagoon and potentially a new tide gate and pump station at San Mateo Creek.

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Key Findings

4. While some properties remain in FEMA flood zones, updated modeling may remove 16th Ave/Palm from designation, and additional projects are planned for 3rd Ave/Norfolk and Hillsdale/McLellan.

5. Larger regional challenges like shoreline and San Mateo Creek protection will require significant future investment and multi-agency coordination.

6. Open channel maintenance is essential to maintaining system capacity and the City is pursuing a multi-agency Citywide Creek Maintenance Permit to facilitate maintenance work.

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Private
Development
Opportunities
• Strengthening runoff
management requirements
• Aligning private improvements
with City system capacity and
climate impacts
• Council direction ultimately
needed to expand stormwater
obligations

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LiDAR Aerial Survey
Funding
Considerations
• Stormwater Fee provides a
stable funding source for
most projects
• Additional financing needed
for larger capital projects
(Marina Lagoon)
• Grant and bond options
under evaluation
Priority Number of
Projects*
Estimated Cost
(in Millions)
Est. Cost without
Marina Lagoon
PS (in Millions)
Very High 11 $160 $39
High 33 $27 $27
Medium 35 $22 $22
Low 58 $24 $24
Total: 137 $233 $112
• Climate Change will add an additional $34
million to the CIP – Total Cost $267 million
• Marina Lagoon Pump Station Improvements
total approximately $121 million

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Localized Ponding
• In general, focus investment in high-
risk locations to deliver
greater systemwide benefit per
dollar invested
• Continue to invest in localized street
ponding (typically shallow and low
risk) to reduce resident impacts
• Keep localized ponding projects
strategic:
• Deliver noticeable improvements
through modest investment
• Proactively prioritize projects
based on benefit and risk
• Prioritize vulnerable populations
(e.g. walking routes near schools
and senior centers)

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LiDAR Aerial SurveyPublic Engagement
• Stormwater Mapping Tool
• Draft Master Plan release for
public review in late
February
• Two public engagement
meetings to be schedule in
Spring 2026

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Feedback Given by Commission

1. The commission is supportive of evaluating potential changes that would encourage private development to contribute toward stormwater solutions.

2. Commissioners broadly supported continuing and potentially increasing investment to address localized ponding projects

3. Many emphasized prioritizing highly visible and heavily used areas like major roads, schools, and parks

4. Some expressed interested in more public engagement beyond the two meetings to build trust and support future investment

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Next Steps

1. Complete internal review and finalize the draft Master Plan

2. Release the draft Master Plan for public review in March 2026

3. Planning for 2 community engagement meetings in Spring 2026

4. Return to Commission City Council with formal adoption by June 2026

5. Initiate design for a subset of “Very High” priority projects in FY 2026–27

6. Continue evaluating funding options for identified capital improvements

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Additional Questions

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San Mateo City CouncilJanuary 26, 2026

San Mateo City Council
January 26, 2026