August 23, 2022

By Barry Nelson, Western Water Strategies, and Ashley Overhouse, Defenders of Wildlife

World Water Week is an international celebration held from August 23 to September 1 annually. The theme this year is Seeing the Unseen: The Value of Water. This is a particularly relevant theme for California right now due to a severe drought and its devastating impacts to wildlife. As the saying goes, you never know how valuable something is until it is gone. That is why Defenders is observing World Water Week by highlighting a management tactic the state is currently promoting: The creation of an “environmental block of water.”

Long before this megadrought, California rivers and wetlands have historically suffered serious damage from dams and excessive water diversions. Reestablishing healthy flows to restore ecosystems is famously difficult given the Golden State’s population, large agricultural industry and over-tapped rivers. To meet this challenge, state and federal regulatory agencies have often adopted requirements for minimum river flows based on an annual cycle in order to meet the needs of keystone species like endangered salmon and steelhead that need water for their annual migration.

Cracked Dirt Landscape - Joshua Tree National Park - California

As an alternative, water agencies, think tanks and others have suggested creating an “environmental block of water.” Instead of a rigid schedule of flows, this approach would dedicate a specific amount of water to an ecosystem. Supporters argue that a block of water managed flexibly, in response to local conditions and scientific analysis, might produce the best results with the least water. For example, over the past 30 years, a block of water provided by the federal Central Valley Project Improvement Act has been used to maintain healthy wetlands and waterbird populations in California’s Central Valley. 

Advocates of this approach argue that it could help reverse the ongoing decline of the San Francisco Bay-Delta estuary, Central Valley rivers, endangered fish species and salmon runs valued by Native Americans and the fishing industry. The concept has been hotly debated, but the idea is far from new.

Defenders of Wildlife has issued a new white paper entitled “Building Blocks” to provide a road map to create successful environmental blocks of water. The paper summarizes 18 similar projects in California, across the West and abroad. Some environmental blocks of water, like the federal water supply for California wetlands, have produced real benefits. Others have remained gridlocked for years. Notably, none of the programs we examined were implemented without significant challenges. 

Spawning Coho Salmon in Stream - Lagunitas Creek - California
Martha Ture

“Building Blocks” does not include a simple prescription. Different settings require different approaches. Instead, this white paper poses a series of questions that can serve as a checklist when creating new environmental water programs. 

Many efforts in the San Francisco Bay-Delta watershed have used the “building blocks” approach and there are currently several controversial proposals for creating a new block of water for the Bay-Delta ecosystem. 

Fish and wildlife have suffered through decades of agency delay in regulating Bay-Delta water quality. Today, the Bay-Delta is suffering from a dangerous algae bloom, called a “red tide,” threatening a number of endangered species. With two enormous water projects, hundreds of dams on more than a dozen rivers, thousands of diversions and numerous imperiled species, the Bay-Delta presents a particularly challenging setting in which to create an environmental block of water. Lessons learned in this ecosystem could be applicable to efforts to protect rivers and wetlands across the nation.

Our new report documents several specific challenges in implementing this “block of water” concept. For example, measuring the amount of water delivered to a farm is simple. But measuring additional environmental water in a river can be surprisingly complicated. In addition, we found that, in many cases, water dedicated to the environment could not be delivered to targeted rivers and wetlands. In some cases, this is because needed canals have not been built to carry water to isolated wetlands. Elsewhere, it is because of unexpected challenges presented by flood management constraints or concerns about water seepage through levees.

Black-Necked Stilt - Kern National Wildlife Refuge - California
Alice Cahill

A quick look at northern California’s Trinity River shows how important this acquired knowledge can be. For decades, Humboldt County has sought to use a 50,000-acre-foot block of water from the Bureau of Reclamation to benefit tribally important salmon runs on the Trinity River and the lower Klamath River. But more than 60 years after the contract for this water was signed, Humboldt County has not secured the release of any of that water.

In addition to looking at past examples, this white paper also examines the need to address equity issues, including environmental justice and Tribal rights. These issues will be critical in developing new environmental water programs. 

“Building Blocks” is centered on the premise that efforts to create new environmental water programs require the careful examination of past attempts—particularly of challenges that prevented progress. In such dire times, California wildlife and communities cannot afford to repeat the mistakes of the past. The “Block of Water” report shows that in California, water for our wildlife is beyond a price point—it is truly priceless. 


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