New Groundwater Policy Brings California Into the 21st Century

Marcus Griswold, Water Resources Scientist, San Francisco

For decades, California's voluntary Groundwater Management Plans have effectively failed to protect the people and ecosystems that depend on this water. Too many people are siphoning off water from our extremely limited resources, resulting in declining groundwater levels, sinking of land, and drying of streams. Without integrated groundwater and surface water management, California’s water users and the environment will face broad challenges accessing water supplies in future years.

But today, Governor Jerry Brown signed into law a number of bills that could halt or reverse these declines.

These new bills would bring the state into the new millennium by requiring, for the first time, a plan for measuring, monitoring, and reporting groundwater use, with the ultimate goal of achieving sustainable groundwater management. Local agencies can take the lead in transitioning to sustainable groundwater management, but if they are unable to do so, the state will step in. 

The timing of the new law could not be better. For more than a decade groundwater levels have been falling. Between 2003 and 2009 freshwater availability has declined by 25 million acre feet in the Central Valley alone â€" almost enough to fill Lake Mead â€" nearly 65% of this due to declining groundwater availability. On the Colorado River, where California gets about 4.4 million acre feet of water, groundwater pumping has led to a loss of 41 million acre feet from the Basin since 2004.

GRACE GW Declines.jpg

Source: University of California Center for Hydrologic Modeling

Since the 1990s the state has encouraged local agencies to work collaboratively to develop groundwater management plans that include a focus on water quality, groundwater recharge, monitoring, subsidence, and managing surface and groundwater concurrently and provide funding for local agencies to do so. The state is also required to map out groundwater basins and to monitor groundwater if no other local agency will. Existing policy states “Protection and management include, but are not limited to, protection of recharge areas and source areas from contamination, protection of groundwater quality, artificial recharge, planned variation of pumping, and conjunctive management of both surface water and groundwater to optimize supplies.” Again, at the local level these strategies were voluntary, but are now required.

One area where the state has been able to move towards groundwater management is through adjudications, often requiring many of the strategies recommended in the new law, such as groundwater monitoring and reporting. As such, adjudicated basins â€" 26 of them â€" are excluded from the requirements to develop a groundwater sustainability plan. In many cases adjudication has successfully reduced overdraft and brought basins closer to balance between water availability and use. Specifically, adjudications in Southern California helped reduce saltwater intrusion that was making water unusable. However, as we saw in the Scott River decision, adjudication does not necessarily translate to sustainable water management.

California Priority Basins.pngThe law recognizes water flowing from streams depends on groundwater

A key piece in the new law is support for reducing impacts of groundwater pumping on the health of surface waters â€" rivers, lakes, wetlands. According to a recent survey of state water managers, about 50% of states have laws that explicitly recognize or address the connection between surface water and groundwater. Historically these waters have been managed separately in California, but the new groundwater law moves the state one step closer to sustainable management of both stating, “Sustainable groundwater management in California depends upon creating more opportunities for robust conjunctive management of surface water and groundwater resources.” The new law also does not affect the state’s existing authority to address the connection between rivers and groundwater under the public trust, as highlighted in the Scott River decision.

The law comes at a much needed time for protecting rivers and streams dependent on groundwater systems. Surface waters in the state are over allocated and increasingly more people depend on access to groundwater â€" a need that has consequences for the sustainability of surface waters.  

Groundwater wells near streams and rivers act like straws, sucking water out of streams and away from streamside riparian habitat, threatening fisheries and downstream water users. Essentially these wells take flows away from streams and rivers and intercept groundwater flows that are flowing towards the streams. Once pumping has sucked all of the water from streams, it could take decades of recharge to return this water to streams. There are numerous cases of this throughout California.

Tulare Basin.jpg

  • In the Tulare basin water from the coast range and Sierras used to recharge the Central Valley, feeding Tulare Lake and surrounding marshes and then the Delta. Excessive groundwater pumping has sucked water from Tulare Lake and marshes, affecting water in the Delta and leaving behind unusable salty soils.
  • In the Mojave groundwater basin, 92 percent of recharge originates from the Mojave River flowing from the San Bernardino Mountains and the San Gabriel Mountains, an important national treasure.
  • In the Cosumnes River, groundwater pumping has drained the river of flows, nearly eliminating baseflow and the ability of the river to support fall run Chinook salmon populations. To reconnect the streams with the aquifer would require an additional 162-243 thousand acre feet a year.
  • In the Santa Rosa Plain in Sonoma County, a USGS model found that groundwater pumping depends on more than half of its water from what is sucked from streams and rivers. Streamflows over the past 30 years have declined in all streams due to pumping â€" by as much as 18,000 acre feet per year.

The new groundwater laws call for all groundwater sustainability plans to consider the impacts of groundwater on surface waters and include strategies for removing barriers to conjunctive management. For the first time local agencies are required to assess impacts to groundwater dependent ecosystems â€" those springs, wetlands, and streams that are connected to groundwater. The state has two years to develop standardized methods for monitoring and best practices for sustainable groundwater management. We look forward to the development of scientifically robust standards and methods.    

Implementation should place water conservation and efficiency first

The second important piece of sustainable groundwater management is reducing water use. The state’s new groundwater law begins to address this important issue, encouraging local agencies to consider "Efficient water management practices." According to the state, this means “reasonable and economically justifiable programs to improve the delivery and use of water used for agricultural purposes.”

By better managing what we have â€" reducing waste, increasing recycling and underground storage when appropriate, and better managing local supplies across regions we can essentially “create” new water. Earlier this year NRDC and the Pacific Institute found that statewide improvements in water efficiency and conservation, reuse, and stormwater capture can provide 10.8 million to 13.7 million acre-feet per year of water in new supplies and demand reductions to the state.

Moving torwards sustainability

However, the most substantial challenge to the law is the timeline for implementation, a process that will require strong commitment by the state and local agencies to achieve sustainable groundwater management. The first is that local agencies do not need to make up for the depletion of groundwater that has already occurred. This means if a basin is already in critical condition, it may be challenging to return to a sustainable level. Additionally, those basins with rivers, wetlands, and springs and the fish that depend on them will need to wait until 2025 to receive broad protection from groundwater pumping.

For the rest of the basins, sustainable groundwater management might not be achieved until 2052. By 2022 all medium and high priority basins must have a groundwater sustainability plan in place to achieve sustainability by 2042. If this doesn’t happen, but the local agency has made an attempt to sustainably manage groundwater they might be granted up to 10 more years to meet sustainability goals â€" 2052.

The state has taken a leap forward in providing accountability for groundwater use and management. Now that such a framework is in place local agencies must meet sustainability goals and provide adequate data on groundwater availability and use. However, the state and local agencies will need to remain vigilant to ensure all milestones are met and that groundwater and the people and ecosystems dependent on it are protected.

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