Stokman Multi-benefit Floodplain Project

Updated on 2/4/2022: Project Lead, Short Project Description, Project Cost, and Project Status

Project Lead: Stanislaus County

Potential Project Partners:
USFWS

Short Project Description:
This property would provide wildlife habitat enhancement and restoration, improved flood management for the adjacent community of Grayson, improved groundwater recharge potential, and improved water quality in the Mid San Joaquin River. In February, 2016, River Partners received funding from the Wildlife Conservation Board (WCB) to purchase this 285-acre property within the San Joaquin River floodplain from a private seller. Acquisition is expected to be complete by the end of Summer 2016. This project is unique in that it has been specifically identified by Stanislaus County as a prime location for groundwater recharge potential. Following restoration of this property, 5-acre feet of groundwater will be returned to the San Joaquin River Watershed, as it will no longer be pumped for irrigation purposes. Additional groundwater recharge from floodwater inundation may also result from the project. Additionally, this project is located within a disadvantaged community block group and disadvantaged community tract as identified by DWR in coordination with Proposition 1 and Proposition 84. Project benefits will enhance this area ecologically, recreationally, and in terms of flood safety and groundwater recharge.

Long Project Description:
River Partners has funds available from WCB to purchase the Stokman Property, located adjacent to the San Joaquin River, in close proximity to the town of Grayson in Stanislaus County, California. Completing the acquisition process for this 285-acre property will be the first step towards habitat restoration of the project site. The ultimate goal for the Stokman Property includes restoration of agricultural lands. Currently the property is farmed in alfalfa and winter wheat/corn rotation using approximately 5 acre-feet of groundwater annually pumped on-site. The property has been identified by Stanislaus County as a natural groundwater recharge area.  Future floodplain inundation would not only enhance wildlife habitat value of the site and alleviate flood pressure for the adjacent community of Grayson, but would allow for greater groundwater recharge to the dwindling San Joaquin River groundwater basin.

In addition to enhanced groundwater recharge potential, this project would confer several benefits to the Central Valley ecosystem. The Stokman Property is immediately adjacent to 10,000 acres of managed wildlife habitat benefitting several federally listed, riparian-dependent wildlife in the San Joaquin Valley. The wildlife habitat benefit potential for the Stokman Property is known from numerous studies and surveys that have been completed in the region since 2002 by project stakeholders including Point Blue Conservation Science, The Endangered Species Recovery Program of CSU Stanislaus, The Nature Conservancy, USFWS, California Department of Fish and Wildlife (CDFW), and California Department of Water Resources (DWR). Agricultural development in the Central Valley has reduced riparian forest cover and connectivity throughout the state. Restoring riparian habitat at sites such as the Stokman Property will recreate the refugia necessary to support migration pathways for birds, fish and terrestrial species.  Multi-benefit projects such as this one are becoming even more important as our climate changes and precipitation patterns continue to alter our watersheds.

Acquisition and restoration of the Stokman Property will also address public safety concerns related to flooding  in the immediately adjacent town of Grayson, CA. River Partners proposes to reduce the 100-year flood risk to Grayson through topographic modification at this property  in the future.  River Partners recognizes the interconnected nature of wildlife habitat function in river corridors and flood management. Approaching restoration with this mindset will allow project partners to develop a forward-thinking multi-benefit flood management improvement and ecosystem enhancement project at the Stokman property.

Unique Project Characteristics:

This project is unique in that it has been specifically identified by Stanislaus County as a prime location for groundwater recharge potential. Following restoration of this property, 5-acre feet of groundwater will be returned to the San Joaquin River Watershed, as it will no longer be pumped for irrigation purposes. Additional groundwater recharge from floodwater inundation may also result from the project. Additionally, this project is located within a disadvantaged community block group and disadvantaged community tract as identified by DWR in coordination with Proposition 1 and Proposition 84. Project benefits will enhance this area ecologically, recreationally, and in terms of flood safety and groundwater recharge.

Project Status In-progress
Project Cost $5 million
Project Timeframe 1-5 years
Cost-sharing Acquisition and subsequent restoration of the Stokman Property offers many cost-sharing opportunities. River Partners has already completed restoration on 2,500 acres at the SJRNWR as well as 600 acres at Dos Rios Ranch. Within the next 10 years, River Partners will have restored over 4,000 acres total in this important ecosystem located at the confluence of the Tuolumne and San Joaquin Rivers.

Restoration of the Stokman Property will contribute significantly to this area that will one day serve as a preserve for native riparian habitat and associated wildlife species. Because of the important contributions the Stokman Property will make to this region, River Partners is likely to incorporate several cost-sharing partners. Previous funders for acquisition and restoration at Dos Rios and Hidden Valley Ranch include the U.S. Department of Agriculture Natural Resources Conservation Service (USDA NRCS), CDFW, DWR, the U.S. Bureau of Reclamation, and the USFWS.

Multi-benefit Project Yes
Types of benefits flood risk management, ecosystem, recreation, water quality, groundwater recharge
Source of Project River Partners

Background Information:
None provided

Latitude:  37.577318
Longitude: -121.170944