by Cariad Hayes Thronson
Big changes are likely on the way for the Delta, thanks to new federal policies, state water management plans, and planned infrastructure. These changes will almost certainly alter the volume, timing and objectives of water flowing through the Delta, but due to recent changes in long-established monitoring programs, the impact on water quality and the ecosystem may be very hard for water managers and scientists to evaluate.
In early December the Bureau of Reclamation issued a Record of Decision adopting a new long-term plan for the coordinated operations of the Central Valley Project and the State Water Project, designed to maximize water deliveries from the projects Under the new approach, the CVP may increase annual water deliveries by between 130,000 to 180,000 acre-feet.
A key component of the plan is the abandonment of the Summer-Fall Habitat Action (SFHA, often referred to as X2), which consists of several components designed to increase the area of low-salinity conditions that favor critically endangered Delta smelt. These include adjusting the operations of the Suisun Marsh Salinity Control Gates, and the release of up to 100,000 acre-feet of fresh water from the projects.
At the time the SFHA was developed, the science suggested that smelt survival is better when there is more fall outflow, according to SWP Environmental Director Lenny Grimaldo. More recent studies have not shown that fall outflow affects smelt survival, although the problem is likely that there are simply too few smelt in the system to be able to discern any effects.
“If you are using a species which is functionally extinct as a metric, it’s damn hard to prove that Fall X2 is doing any good,” says Jeff Mount of the Public Policy Institute of California.
Regardless of the effect on smelt survival, the SFHA releases have clear benefits for water quality and the wider ecosystem, says Delta Water Master Jay Ziegler.
“The summer X2 obligation is beneficial for all listed species and has a very positive salinity effect in the western delta,” says Ziegler. “The practical effect of unilaterally reprogramming water intended for environmental flows is that it brings us closer to the edge of the salinity conditions necessary to support not just fisheries needs, but wider water quality objectives.”
The question then is who will be responsible for ensuring that those water quality objectives are met.
“Three-and-a-half to four million acre-feet of water per year has to flow out of the Delta and into San Francisco Bay in order to keep the Delta fresh enough just to use it,” says Mount, referring to use for irrigation and drinking water, and more water is needed to meet environmental standards. For decades, “the state and federal governments have shared the burden of meeting those standards.” If the federal government does not share the burden, “it falls entirely on the state,” says Mount.
How all this plays out remains to be seen. However, with regard to smelt, Grimaldo says DWR is “leaning into” science to determine what other steps can help the beleaguered fish.
“We are looking at a portfolio of actions that can benefit smelt, such as how we operate the gates to enhance turbidity, managing wetlands and duck clubs to produce more food, and removing submerged aquatic vegetation.” He adds that developing new tools and population models will be critical to the success of these efforts. “Our goal is to increase operational flexibility, maintaining water supply while protecting species, and we need better information to help do that.”
“Better information” may be increasingly hard to come by, say Ziegler and others, as the federal government slashes budgets and staff at the agencies that monitor and manage the Delta, and shutter or offload critical monitoring programs.
Last fall the Bureau of Reclamation abruptly declined to renew the US Geological Survey’s longstanding contract to conduct flow and water quality monitoring for the Delta Monitoring Program. The program, which has long operated in tandem with DWR monitoring, consists of a network of 54 stations throughout the Delta that monitor salinity and flows, and provides essential information that informs operations of the water projects, as well as dozens of other programs.
The shift has fractured the longstanding state-federal monitoring partnership, and raised serious questions about the data coming from the new monitors.
“This network has been in operation for 30 years and encompasses a comprehensive view of flows coming from the San Joaquin, Sacramento, and Cosumnes rivers and all the tributary inflow relationships to the Delta, as well as providing an understanding of the tidal exchange, riverine and flow dynamics,” says Ziegler.
“A lot of people rely on that data. Certainly the state and federal regulators do, and also Contra Costa Water District and others who use that data for their operational decisions,” says Jay Lund of UC Davis. “And it’s very useful to have very good sets of data to calibrate the models that we use for all the places and times in the Delta where we don’t have data.”
The issue is clearly quite touchy. Numerous experts Estuary News Group approached for interviews insisted only on speaking off the record. In a statement a BOR representative said “the Bureau of Reclamation continues to monitor Delta flow and water quality. The only difference is that our vendor has changed. No monitoring programs are being discontinued.”
However, as of the end of January, it’s unclear whether monitoring is actually occurring. Twenty-one of the monitoring stations, which normally update continuously to an online dashboard, had not reported since October when the contract shifted from USGS to a private consulting company. Ziegler and others say BOR has indicated that reporting will begin again soon (it was supposed to begin one month after the contract started). If and when the data stream does recommence, many questions remain about the reliability and quality of the data.
“The USGS is the standard by which you judge others,” says Lund. “They are typically the most reliable. They have the best, most consistent quality control standards. They’re very diligent and very good, and it makes it a little bit more expensive, and sometimes makes their data a little bit more delayed. But they are the standard by which you judge data, and to have them not be performing that role in the Delta lowers the bar on data quality and data availability.”
Indeed, a recent National Academy of Sciences report on CVP/SWP operations, commissioned by Reclamation itself, noted that “the leadership role of the USGS in designing, implementing, and making available state-of-the-science monitoring in the Delta, Bay and watershed is the bedrock of this exemplary science and research endeavor.”
“The role of the USGS has been as the Integrator of the data collected from the USGS, the Bureau and the Department of Water Resources in applying the same data standards and quality control,” says Ziegler. “We’re hopeful that the Department of Water Resources will play that role in the future, but that’s a big undefined area. In other words, how do we discern whether the data now provided from the private companies is of the same data standards as the data that DWR is providing?”
The Bureau has also notified the federal agencies that conduct ecological monitoring in the Delta ( National Marine Fisheries Service, the National Oceanic and Atmospheric Administration and The U.S. Fish and Wildlife Service) that it is discontinuing those programs and contracting with private companies to conduct the work. The consequences for Delta science going forward are unclear.
“Much of the science, and what we know about the Delta and how it works today, has really been dependent upon science endeavors that are jointly sponsored by the Bureau of Reclamation and the Department of Water Resources,” says Ziegler. “The greater public is really dependent upon those relationships continuing.”
These monitoring shifts are taking place against the backdrop of the imminent update of the State Water Resources Control Board’s Bay-Delta Plan, and ongoing efforts to build the Delta Conveyance Project and new water storage such as Sites Reservoir, all of which will affect how much water flows through the Delta and when. They will doubtless make it harder than ever to obtain reliable information essential for sound estuarine management for all benefical uses of these waters, especially if California’s snowpack doesn’t increase and drought conditions dominate this summer and fall.
“In the absence of data, if we’re honest about it, we’re going to be guessing more than knowing more,” says Ziegler. “And that just can’t be in the long term interest of the Bureau of Reclamation, or the State Water Project, or the people of California, or the wildlife that we’re trying to bring back in the Delta.”
The story was produced by Estuary News Group. A follow up story is planned for March.
