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File #: 2020-0944   
Type: Consent Calendar Item Status: Agenda Ready
File created: 9/10/2020 In control: Sonoma County Water Agency
On agenda: 10/20/2020 Final action:
Title: Flood Warning Monitoring Network Maintenance through Fiscal Year 2024/2025
Department or Agency Name(s): Sonoma County Water Agency
Attachments: 1. Summary Report, 2. Agreement
Date Action ByActionResultAction DetailsMeeting DetailsVideo
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To: Board of Directors, Sonoma County Water Agency

Department or Agency Name(s): Sonoma County Water Agency

Staff Name and Phone Number: Carlos Diaz 547-1956

Vote Requirement: Majority

Supervisorial District(s): First, Third, Fourth, and Fifth




Flood Warning Monitoring Network Maintenance through Fiscal Year 2024/2025



Recommended Action:

Recommended action

Authorize Sonoma County Water Agency’s General Manager to execute an agreement with OneRain Incorporated for ongoing flood warning monitoring network system maintenance and support services through June 30, 2025, in the not-to-exceed amount of $342,500. (First, Third, Fourth and Fifth Districts)



Executive Summary:

In response to the 2017 firestorm, the Sonoma County Water Agency (Sonoma Water) engaged OneRain Incorporated (Consultant) to install a flood warning monitoring network consisting of rain and stream gauges throughout the Tubbs and Nuns fire burn areas. Consultant also provided a web-based software to receive and display data and to provide early detection of post-fire flood conditions in burn scars and areas downstream that could be impacted by flash floods and debris flows. The system has since been expanded to monitor other Sonoma Water flood management reservoirs and Mirabel facilities. This item requests authorization of five years of network maintenance and software renewal. Under this Agreement, Consultant will provide ongoing maintenance and support services for the flood warning monitoring system.




As a result of the Sonoma Complex Fires in 2017, dangerous conditions threatened numerous properties in and around the Tubbs and Nuns fire burn areas of Sonoma County, including some properties owned or maintained by Sonoma Water.  A Watershed Emergency Response Team (WERT), consisting of CalFire, California Geologic Survey, California Natural Resources Agency, California Governor's Office of Emergency Services, California Department of Water Resources, and the California State Water Resources Control Board, initiated efforts to assess the risks of landslides and flooding posed by fire-impacted zones throughout the area.  This assessment was used to develop preliminary emergency protection measures needed to avoid life-safety threats.

The WERT analyses for the Tubbs and Nuns fires developed recommendations for watch and warnings for hazards, including an early warning system for flood and landslide risks.  The WERT analyses concluded that some of the burn areas would exhibit elevated runoff and streamflow rates as well as significantly increased erosion.  The analyses also indicated a higher potential for landslides, debris flows, and flash floods that could be a risk to public safety and property.

In March of 2018, Sonoma Water contracted with Consultant to install a flood warning monitoring network consisting of rain and stream gauges throughout the Tubbs and Nuns fire burn areas to provide early detection of post-fire flood conditions.  This flood warning monitoring network provides the National Weather Service with the intelligence it needs in real-time to issue flash flood warnings to be relayed via the Emergency Alert System and Wireless Emergency Alert.  The flood warning monitoring network is also used by Sonoma Water field crews and local emergency officials during and after storm events to respond to hazard conditions identified by the monitoring network. The network has the ability to alarm and send email and text notifications when certain conditions or thresholds have been met, and all real-time data is available to the public through a website. In the first 2 years of the system being in place, the public accessed the website over 2.5 million times. The system was further expanded in FY 19/20 to monitor stages in Sonoma Water’s flood management reservoirs and at the Mirabel facilities.


Given the recent Kincade, Walbridge and Glass fires, Sonoma Water has requested PG&E settlement funding to expand the program into these recent burn-scars and surrounding areas. However, at this time Sonoma Water has funds to maintain and support the existing network. Pending the outcome of settlement dollars, Sonoma Water will return to the Board with an agreement to accomplish program expansion.


This flood warning monitoring network requires ongoing maintenance and support to ensure optimal functionality so it can continue to provide real-time data to National Weather Service, emergency officials, and the public and to inform Sonoma Water operations.



On November 20, 2017, for the prior agreement with Consultant, Sonoma Water emailed eight firms to request proposals for the installation, configuration, and support of a flood warning monitoring network and selected Consultant to perform the initial network setup and provide web-based software that readily makes the data available to Sonoma Water, the National Weather Service, and the general public.


For the proposed agreement, a competitive selection process was not completed, and a Single/Sole Source Waiver was obtained from the County of Sonoma, General Services Department, Purchasing Division. A Single/Soul Source Waiver was needed because Consultant’s services and equipment are required to match and accommodate components and software already in use by Sonoma Water.



Under the proposed agreement, Consultant will provide ongoing maintenance and support services for the existing flood warning monitoring network.

The cost of services will not exceed $342,500; the term end date is June 30, 2025.



Prior Board Actions:

08/20/2019:  Approved agreement between Sonoma Water and OneRain Incorporated to install, configure, and support the expansion of the existing flood warning monitoring network.  Cost $178,900; term end December 31, 2020. 

12/05/2017:  Approved agreement between Sonoma Water and a consultant [not determined at the time of the Board meeting] for Burn Area Watershed Protection:  Flood Warning Monitoring Network in an amount not to exceed $400,000 for a term of twelve months.



Fiscal Summary


FY 20-21 Adopted

FY21-22 Projected

FY 22-23 Projected

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Additional Appropriation Requested




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Narrative Explanation of Fiscal Impacts:

Budgeted amount of $72,500 is available from FY 2020/2021 appropriations for the Flood Control Zones’ 1A and 3A funds. The remaining $132,000 will be budgeted in subsequent fiscal years.  No additional appropriation is required.


Staffing Impacts:




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Narrative Explanation of Staffing Impacts (If Required):






Related Items “On File” with the Clerk of the Board: