Protecting Groundwater and Reversing Subsidence in the Coachella Valley

Protecting Groundwater and Reversing Subsidence in the Coachella Valley

CVWD's Whitewater Groundwater Replenishment Facility.

PHOTOS COURTESY OF CVWD.

The Sustainable Groundwater Management Act (SGMA) is a 2014 California law intended to preserve and protect California’s precious groundwater resources. The law required all hydrological basins and subbasins across the state to be assessed for their priority and overdraft status and then to develop appropriate plans for the sustainable management of their groundwater. Coachella Valley Water District (CVWD) was able to prove that its existing groundwater management activities lived up to the SGMA standard, obviating the need for new plans. Moreover, its groundwater management is resulting in a significant increase in groundwater levels and even the reversal of ground subsidence.

In this interview, Zoe Rodriguez del Rey, the manager of CVWD’s water resources division, speaks with Irrigation Leader about the requirements of SGMA and the results of the district’s management activities.

Irrigation Leader: Please tell us about your background and how you came to be in your current position.

Zoe Rodriguez del Rey: I have a bachelor’s degree in biology and a master’s in environmental science, but my primary focus has always been on water. During my undergraduate studies, I worked with a group at the University of New Orleans that combined research and practical application, working to restore Lake Pontchartrain in New Orleans. Thereafter, I secured a job with the City of Portland, Oregon’s Water Bureau, working in their water quality and compliance division of operations, which included both groundwater and an unfiltered surface water system. I fell in love with the planning and implementation it takes to operate a water system and ensure that folks have a long-term, reliable, sustainable water supply. That led to the opportunity 2 years ago to join CVWD, where I am now the manager of the water resources division.

Irrigation Leader: Please tell us about CVWD.

Zoe Rodriguez del Rey: CVWD covers 1,000 square miles, mainly within Riverside County but also stretching into Imperial and San Diego Counties. We serve approximately 110,000 domestic accounts. We provide seven water-related services: domestic water service, sanitation, water recycling, regional flood control protection, groundwater replenishment, agricultural irrigation, and agricultural drainage.

Our two largest sources of water are imported water, which makes up a particularly large portion of the mix, and local groundwater. We also use a small amount of local surface water, although we don’t use it directly, like other purveyors in the valley do. This could be broken down further by sector. For example, our agricultural sector primarily uses imported surface water. Imported water is also used to replenish the groundwater basin.

Irrigation Leader: What is SGMA and why was it introduced?

Zoe Rodriguez del Rey: There are areas of California that are heavily reliant on groundwater and are overdrafting groundwater supplies to an extreme degree. The Central Valley, which has a large agricultural sector, is seeing the effects of long-term groundwater pumping. Groundwater is an important resource, and we needed to start thinking about how we can manage it in a sustainable manner and ensure that system outflows aren’t greater than inflows. That was the main driver for the establishment of SGMA. There has been strong collaboration among a broad spectrum of individuals, businesses, and state entities to implement the law.

Irrigation Leader: What does SGMA require of districts like CVWD?

Zoe Rodriguez del Rey: Initially, the Department of Water Resources (DWR) had to do an assessment of all the groundwater basins in California. It designated each basin as either low, medium, or high priority and either critically overdrafted or not. Once a subbasin was identified as being medium or high priority, then certain local agencies, for example water purveyors, had the authority to form groundwater sustainability agencies (GSAs).

SGMA lays out which entities can form a GSA. Once formed, the GSA must be approved by the DWR. There are places in California where new agencies were formed to fill the GSA function, but for the most part, the entities that form GSAs are existing agencies. CVWD provides services in two subbasins that are medium priority and not critically overdrafted. In both cases, local water agencies came together and became GSAs in their service areas and then decided to work collectively to comply with SGMA. The next step was to develop a groundwater sustainability plan (GSP) that charted out how the subbasin was going to become sustainable within 20 years. SGMA did allow for subbasins with existing plans that were functionally equivalent to GSPs to submit those rather than developing something new. The GSAs tied to the subbasins that we manage decided to collaboratively submit water management plans that had already been developed, drawing on stakeholder input that started in the 1990s, that met the intent of the goals of SGMA. The plans were submitted in late 2016, and in summer 2019 we learned that the DWR had approved both plans, eliminating the need for new GSPs. That puts us in a group of only 9 of the approximately 109 medium- and high-priority basins.

Critically overdrafted basins were required to submit GSPs by January 2020; those deemed not critically overdrafted must submit them by January 2022. In all cases, a basin’s sustainability goals must be achieved within 20 years of the initial submission. To ensure that that happens, basins are required to undertake annual reporting as well as an assessment and updating of their plans every 5 years. We’re getting ready to work on our first 5-year update of the plans we submitted in 2017, which will be due by January 1, 2022.

Irrigation Leader: Did you have to alter your existing management plans to ensure that they met the specific requirements of SGMA?

Zoe Rodriguez del Rey: We did not modify our existing operational plans, but when we submitted them, we provided additional reporting and information that showed that they were the functional equivalent of a SGMA-mandated GSP. The bridge documents we submitted included items such as reports on groundwater conditions and replenishment programs that we were already producing annually. The fact that the state accepted our alternative plans demonstrates the level of success that CVWD and its partners have had managing our groundwater resources.

Irrigation Leader: What results have you been seeing from your groundwater management activities?

Zoe Rodriguez del Rey: The results have been positive. While other places are seeing their groundwater levels going down, ours are coming up; while other areas are worried about ground subsidence, CVWD is actually seeing a complete leveling off of subsidence in some areas and even an uplift in others.

One of the main things we have been focusing on is maximizing the use of our imported water supplies. Through the construction of replenishment facilities and through agreements that allow us to store water for partners during wet years and provide their allocations during dry years, we are effectively balancing the use of pumped groundwater and imported surface water. While we historically focused mostly on agriculture, we are now addressing other areas of high water demand, such as turf irrigation, golf courses, and schoolyards. We are also targeting conservation. CVWD has some amazing conservation programs in which we work with people to make sure that they’re being efficient. We are pursuing grants and other forms of funding to help provide customers with the means and incentives to save water. As a result, in the upper-west part of the basin, we’ve seen stable water level increases of upwards of 20 feet. Moving to the east, where there’s a lot of agriculture, we’ve seen increases of up to 90 feet as well as the return of free-flowing artesian conditions and increases in drain flows, which are indicators that groundwater levels are rising. In the mid-valley, we’ve seen the situation stabilizing, but work remains to be done. We are working to expand the number of customers connected to a pipeline, allowing us to get a lot of golf courses off of groundwater pumping and onto imported or recycled water.

Irrigation Leader: In addition to concerns about water quantity, do you also have any concerns about groundwater quality?

Zoe Rodriguez del Rey: Certainly. You cannot be a water purveyor without being concerned about water quality. We continuously watch for new or changing regulations and closely observe use patterns to ensure we have the flexibility to effectively respond to emerging water quality issues. We’re fortunate in that we have an extensive well field and a fair amount of operational flexibility. We drill our wells deep and we have a long history of groundwater monitoring, so we know where there are potential issues.

Irrigation Leader: What is your vision for the future?

Zoe Rodriguez del Rey: My vision for the future is focused at the moment on our first 5-year plan update. I intend to focus all my energies on ensuring that we effectively assess and update that plan with the best information available. We are working with some amazing partners, stakeholders, internal staff, and consultants in a collaborative way. Throughout, we are taking into account what has worked, what is changing and what needs to be adjusted. Ultimately, the goal is to make absolutely sure that this valley continues to have a sustainable and reliable water supply far after everyone that you’re talking to here has retired.

Zoe Rodriguez del Rey is the manager of Coachella Valley Water District’s water resources division. She can be contacted at zrodriguezdelrey@cvwd.org.