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Hidden Valley Ranch

An Expansion of the Dos Rios Ranch Ecosystem Improvement and Flood Management Project

Following high river flows in 2011, the fields of Dos Rios Ranch and the adjacent Hidden Valley Dairy were damaged by sediment deposition and scour.

Located immediately adjacent to the 1603-acre Dos Rios Ranch (owned by River Partners) and the 8,000-acre San Joaquin River National Wildlife Refuge, the Hidden Valley Ranch is a critical parcel of floodplain land that works in tandem with the Dos Rios Ranch to provide public safety, ecosystem improvement, community enhancement, and wildlife-friendly farming along the San Joaquin River Corridor in Stanislaus County.

Meeting Multiple Objectives

For over ten years, a coalition of local interests has worked collaboratively to develop this important regional project to provide multiple improvements including: improved environmental conditions that benefit our agricultural economy, recovery of threatened and endangered species to reduce future regulatory conflicts, enhanced public safety through improved flood management, enhanced recreation opportunities including hunting and fishing.

The Dos Rios Ranch project is supported as a high priority in these plans and programs:

  • Stanislaus County General Plan - Conservation and Open Space Element (1994)
  • Recovery Plan for the Upland Species of the San Joaquin Valley (1998)
  • Central Valley Vision for California State Parks (2003)
  • Lower Tuolumne River Parkway (2005)
  • Central Valley Joint Venture Implementation Plan (2006)
  • Bay-Delta Conservation Plan
  • San Joaquin River Restoration Program
  • East Stanislaus Integrated Regional Water Management Plan (2012)
  • Central Valley Flood Protection Plan (2012)
  • Mid San Joaquin Regional Flood Management Plan (draft 2013)

Improved environmental conditions that benefit our agricultural economy

Water Supply: This project has the potential to permanently reduce riparian diversions from the San Joaquin and Tuolumne Rivers, leaving more precious water in the rivers and streams for other uses. Dos Rios Ranch and the adjacent Hidden Valley Ranch comprise four riparian diversion rights that in total can draw over 5,000 acre-feet from surface waters annually. As habitat and conservation uses are developed on the properties in the coming ten years, some of the existing surface water diversions can be reduced or retired.

Water Quality: This project has the potential to revegetate river banks and provide protective vegetative cover to tilled lands in the primary floodplain of the state’s second largest river. Such protective cover can reduce sedimentation in surface waters and serve as a sediment trap during high river flows.

Recovery of threatened and endangered species to reduce future regulatory conflicts

This project has the potential to recover wildlife species from the brink of extinction. At the southern end of the historic population range of riparian brush rabbits, the project is a unique opportunity to contribute to the de-listing process of the USFWS. Additional protected species that will benefit from this project include: riparian woodrat, Sandhill crane, least Bell’s vireo, yellow warbler, Swainson’s hawk, steelhead trout, Chinook salmon, and Valley Elderberry Longhorn Beetle.

Enhanced public safety through improved flood management

Flooding is common along the river corridor in Stanislaus County. Large floods in 1983, 1986, 1995, 1997, 2006 and 2011 cause millions of dollars in damages to local farmers and communities.

Dos Rios Ranch and Hidden Valley Ranch together comprise all flood-prone lands within Reclamation District 2092. Managed together, these lands can provide transient floodwater storage of up to 10,000 acre-feet, contributing substantially to downstream flood stage reduction and potential revision of flood management guidelines for Don Pedro Dam.

The flood protection benefits of this project have been recognized by the California Department of Water Resources and the Central Valley Flood Protection Board in the 2012 Central Valley Flood Protection Plan. In 2013, Stanislaus County and Reclamation District 2092 (Dos Rios Ranch) entered into a partnership to develop a vision for a flood-safe Stanislaus County. An important component of this plan will include use of flood-prone lands such as these to store flood waters at appropriate times to minimize flood damages to downstream areas.

Enhanced recreation opportunities including hunting and fishing

The San Joaquin Valley has long been recognized as an important hunting and fishing destination in the Western US. This project will enhance populations of game species including fish and waterfowl by providing shaded riverbanks for fish to rest during their migrations, and providing a food source for migrating waterfowl. By enhancing opportunities for outdoor recreation in the middle of Stanislaus County, this project will enhance local tourism potential.