Irrigation Leader
Photo of Lake McClure during a drought. The original Exchequer Dam, normally submerged, is exposed.
District Profile,  Interview

Expanding Storage to Sustain Agriculture in the San Joaquin Valley John Sweigard of Merced Irrigation District

With rights dating back to the 1800s, Merced Irrigation District (MID) is a senior water rights holder on California’s Merced River, a tributary of the San Joaquin River. The irrigation district formed in 1919 and built Exchequer Dam, creating Lake McClure. MID completed the 490-foot New Exchequer Dam in 1967, impounding more than 1 million acre-feet of surface water, creating flood control space, and providing a generating capacity of 95 megawatts of renewable hydroelectric power. MID currently serves approximately 2,200 growers and more than 130,000 acres of highvalue orchards and row crops in the eastern San Joaquin Valley.

Over the years, and like most water providers in California, MID has been working to increase its water supply capacity. On June 6, the U.S. House of Representatives passed H.R. 8, the Water Resources Development Act of 2018. The legislation included an amendment from Congressmen Costa and Denham of California, as well as Congressmen McClintock and Garamendi, intended to assist MID in its efforts. Specifically, it would allow the U.S. Army Corps of Engineers to accept funding from nonfederal hydroelectric operators in order to review and update reservoir operations manuals. Such a review is a critical first step in MID’s overall effort to increase the end-of-summer carry-over storage capacity of Lake McClure by 57,000 acre-feet. A review of the operations manual for Lake McClure would allow the Army Corps to consider new science and data and would be a crucial first step toward increasing the carry-over storage capacity of Lake McClure.

General Manager John Sweigard has been leading MID in its efforts to sustain and maintain a reliable supply of water and power for its farmers and customers. Mr. Sweigard has a deep connection to the district and its agricultural history: His grandfather owned several hundred acres of rangeland across from the spillways at New Exchequer; some of that acreage is now under water. Irrigation Leader’s editor-in-chief, Kris Polly, spoke to Mr. Sweigard about the project, how to navigate the complexities of surface water development, and sustaining water supplies for the long term.

Kris Polly: What types of crops are grown in your district, and how are they irrigated?

John Sweigard: MID has seen a shift from annual crops to permanent crops, with orchards accounting for roughly 50 percent of irrigated acres in the district. However, there’s still a lot of support for the dairy industry in the form of alfalfa and corn. We also have small community farms that grow 20 or 30 different vegetables on a small parcels. Our growers produce every type of crop you can think of, including corn, tomatoes, and beans.

This area is one of the few areas of the world where farmers can grow organic sweet potatoes, so we have 6,000–8,000 acres of organic sweet potatoes. Surface water is very important to those growers. Water that’s higher in salinity levels, like the groundwater found here, affects the storage and the shelf-life of sweet potatoes; they start to degrade quickly if they don’t have clean surface water as part of their organic operations.

Our growers have been, and continue to be, moving rapidly toward technology and low-volume pressure systems. Flood irrigation is becoming less of a thing; drip and micro-sprinklers are taking over rather quickly.

Kris Polly: Please tell us about your district’s water supplies and the effort to increase storage behind New Exchequer Dam.

John Sweigard: We’re a conjunctive-use district, so we generally rely on our surface water when it’s available. We allow groundwater recharge from our distribution system, and we have some intentional groundwater recharge projects. Generally, we rely on groundwater only as needed in drought years. Through that water balance, the district contributes a net positive to the local aquifer.

That said, groundwater is still a depleting resource, and we’re one of the high-priority basins in California addressing sustainability through the Sustainable Groundwater Management Act. As with any water management agency, we’re always planning for the future and looking at trends to manage our resources.

New surface water storage projects in California are few and far between, especially when they are geared toward agriculture as opposed to urban areas. A lot has changed since when New Exchequer was built; we have a lot more data on runoff and operations. We think there is a better, more modern way to operate New Exchequer for all its purposes.

The MID storage enhancement would raise the spillways at Lake McClure and enable the Army Corps to have use of that new space on the top of the reservoir if needed. The Army Corps will also be able to reevaluate operations via its storage and operations curves based on new information.

We believe there is an opportunity to adjust the operations curves that ultimately would allow us to carry more water over at the end of the irrigation season in October. Our numbers indicate that approximately 57,000 acre-feet could be carried over from a wet year when we have extra water—like last year—and used in some subsequent year for water supply or any other purpose of the project. That’s the general concept.

To me, this is a water resource management engineering exercise. Even though the Army Corps has the directive to update its operations manuals, it has limited resources and a variety of priorities. Existing regulations limit the ability of the Army Corps to enable MID to fund its analysis. That is what this new legislation [included in the Water Resources Development Act of 2018] does—it allows the Army Corps to accept funding from local project owners to reevaluate flood control curves. Those changes will enable MID to move forward with the continued feasibility analysis of our spillway.

Kris Polly: How has the Army Corps been involved in the expansion process?

John Sweigard: We’ve had ongoing discussions with the Army Corps. From my perspective, the Army Corps seems willing to look at the flood control curves, but for existing funding and priority limitations. I get the feeling that if we can get the funding issue fixed, then the Army Corps would be willing to take a look at our proposal.

We think we have a good case for modifying the operating curves and creating significant improvements for carryover storage. We’ll generally have a deeper pool in the winter months, creating cooler water. We’ll have more water supply, which will help with hydroelectric generation to meet new demands, whatever those demands might be. Better management of wet-year water supplies benefits everybody. If we’re willing to pay for it and not ask anybody else to pay for it, I think it’s something that makes a lot of sense.

Kris Polly: Beyond your need for more storage and management flexibility, what are some of the other challenges the district is currently facing?

John Sweigard: The Sustainable Groundwater Management Act is a big deal because we’re within a high-priority, overdrafted basin. We are undertaking a lot of activities to become compliant with the new groundwater law.

In addition, we are currently in the process of relicensing our hydropower plant at New Exchequer Dam with the Federal Energy Regulatory Commission (FERC). Our final license application is in. It is likely to be quite a few more years before the environmental considerations of the licensing process get resolved.

Our surface water situation will continue to be challenged by both FERC relicensing and the California State Water Resources Control Board. The board, through the Water Quality Control Plan for the San Francisco Bay/Sacramento-San Joaquin Delta Estuary, has been pushing for substantially more water to bypass storage and diversion of our communities’ water supply for the purported support of salmon and other interests elsewhere. That’s a major problem for us, and quite frankly, we totally disagree with the board’s approach and flawed science.

Kris Polly: Will the expansion of surface storage provide MID with more flexibility to meet all these different requirements?

John Sweigard: I think that’s a fair statement. The salmon issue is a complex one, but it’s even further complicated on the Merced River, because the river below our project has been altered—not by us, but before us—by historic dredge mining. There are a couple projects restoring the river from these deep channels where the dredgers moved rock. The goal is to create a river that looks and acts more like a normal river: one that can support salmon by creating better spawning habitat and that is combined with out-migration flows that make sense and are sustainable.

MID has spent millions of dollars developing the best science possible on the Merced River. We are promoting the Merced River SAFE Plan (Salmon, Agriculture, Flows, and Environment), which embraces a combination of both changing flows and river restoration. We believe in it, our biologists believe in it, and we think that we have more expertise on the Merced River than disconnected folks in Sacramento. We have pledged funding for SAFE projects, and we are more than willing to sit down with agencies and the nongovernmental organizations to discuss our role in funding projects that are sustainable for all.

We’ve been here on the ground for 100 years and have seen what does or does not occur. MID is willing to create solutions that will work, but we are not going to be party to a water-only solution that robs our community of its economy and water and puts people out of business in an area that provides vital food supply for the entire country. We’re reasonable people, but we will also stand up for what’s right.

Kris Polly: How did you come to the district, John?

John Sweigard: My history with the district dates back quite a while. I grew up on a cattle ranch in the district. I was a ditch tender at MID for two summers while I put myself through engineering school at Cal Poly, where I worked for the Irrigation Training and Research Center. From there, I managed a smaller district in the San Joaquin Valley for 13 years. I was fortunate to have the opportunity to come back to Merced, and I’ve been here for nearly 9 years as the general manager.

Kris Polly: You have a long history with the district.

John Sweigard: I care about the community, and I’m here for the right reasons. I do everything I can to be helpful and to ensure that folks who want to choose agriculture as their way of life continue to have the opportunity to make that choice.

Kris Polly: Where do you want the district to be in 10 years?

John Sweigard: Our goal is to provide reliability for the future and eliminate the unknown. So, we are interested in finding sustainable arrangements with all the right folks on managing the Merced River in a responsible way that also allows us to maintain a water supply that meets the needs of our growers.

We have undertaken several efforts to try to resolve some of the challenging issues and to develop partnerships that create some certainty for agencies, nongovernmental organizations, MID, and our growers. We have spent years in some of those processes, and have pulled away because we just don’t feel like it’s worth the time when the other side is not willing to compromise. It’s their way or no way.

Kris Polly: What is your advice to other managers looking to undertake storage expansion and create certainty for the long term?

John Sweigard: You have to have a lot of patience, provide a lot of education, and be prepared to shift gears at any time. Even when a solution might be obvious from a water planning or engineering perspective, you have to be flexible enough to find another workable solution from a nonengineering perspective.