
Following the 2017 failure of the concrete spillway on Oroville Dam, the California Division of Safety of Dams ordered the detailed evaluation of numerous dams throughout California. Through coordination with the Division of Safety of Dams, Marin Water is using a phased assessment approach, outlined below.
- In the first phase, which was completed in 2019, Marin Water and its contractor identified and repaired minor, surface imperfections at each of the three spillways.
- The second phase, which is currently in progress, involves structural evaluation centered on sub-surface imaging and exploration, including ground-penetrating radar and other methods for verifying structural integrity of the spillways.
Construction UpdateWork on the District's Dam Spillway Repair Program was completed in the fall of 2024. |
Soulajule Dam Spillway Repair

Project | Soulajule Dam Spillway Repairs |
Program | A1A05 Replacements ‐ Reservoir/Dam Facilities |
Project Number | D21014 |
Contact | Matthew Steiner | MSteiner@marinwater.org |
Project Description
This project entails the condition assessments of Soulajule Dam on Soulajule Reservoir. Phase I included the repair of non-structural concrete including spalls, surface defects, offsets, sub-drain cleaning, cracks and joint sealing on the spillway of Soulajule Dam. These repairs are the output of the Phase I condition assessments conducted in accordance with Division of Safety of Dams requirements. Phase II work will include a more intensive assessment including core sampling, sub-drain investigation and ground penetrating radar.
Benefits
Regular maintenance of dam spillways is common practice to ensure the continued operation of the facility.
Schedule and Status
Phase I completed. Phase II design underway.
Phase II Design: Fall 2021 - Summer 2023
Phase II Construction: Summer 2023 - Fall 2024
Funding Sources
Capital Maintenance Fund | Other Funding Sources | Total |
$639,000 | - | $639,000 |
Kent Dam Spillway Repair

Project | Kent Dam Spillway Repairs |
Program | A1A05 Replacements ‐ Reservoir/Dam Facilities |
Project Number | D21013 |
Contact | Matthew Steiner | MSteiner@marinwater.org |
Project Description
This project entails the condition assessments of Peters Dam on Kent Lake. Phase I included the repair of non-structural concrete including spalls, surface defects, offsets, sub-drain cleaning, cracks and joint sealing on the spillway of Peters Dam. These repairs are the output of the Phase I condition assessments conducted in accordance with Division of Safety of Dams requirements. Phase II work will include a more intensive assessment including core sampling, sub-drain investigation and ground penetrating radar.
Benefits
Regular maintenance of dam spillways is common practice to ensure the continued operation of the facility.
Schedule and Status
Phase I completed. Phase II design underway.
Phase II Design: Fall 2021 - Summer 2023
Phase II Construction: Summer 2023 - Fall 2024
Funding Sources
Capital Maintenance Fund | Other Funding Sources | Total |
$801,000 | - | $801,000 |
Nicasio Dam Spillway Repair

Project | Nicasio Dam Spillway Repairs |
Program | A1A05 Replacements ‐ Reservoir/Dam Facilities |
Project Number | D21012 |
Contact | Matthew Steiner | MSteiner@marinwater.org |
Project Description
This project entails the condition assessments of Seeger Dam on the Nicasio Reservoir. Phase I included the repair of non-structural concrete including spalls, surface defects, offsets, sub-drain cleaning, cracks and joint sealing on the spillway of Seeger Dam. These repairs are the output of the Phase I condition assessments conducted in accordance with Division of Safety of Dams requirements. Phase II work will include a more intensive assessment including core sampling, sub-drain investigation and ground penetrating radar.
Benefits
Regular maintenance of dam spillways is common practice to ensure the continued operation of the facility.
Schedule and Status
Phase I completed. Phase II design underway.
Phase II Design: Fall 2021 - Summer 2023
Phase II Construction: Summer 2023 - Fall 2024
Funding Sources
Capital Maintenance Fund | Other Funding Sources | Total |
$754,000 | - | $754,000 |
Contact Information
Marin Water Construction Management team: 415-945-1560