Aquifers also help move water from areas of recharge finding to areas dominated by extraction that are miles or — in very large aquifers — a few tens of miles away. Unfortunately, in many areas of California we have not been replenishing this account sufficiently during wet years. Groundwater resources across California’s agricultural regions have been more stressed during the current drought than at any other time in history finding. In most wells, depth to groundwater has exceeded that of the same or nearby wells in the 2007–2009 drought, and exceeds the depths recorded in the mid-20th century, prior to local, state and federal water projects finding coming on-line. The demand for groundwater has been increasing due to the increased acreage of intensively grown crops, large-scale conversion of range land and field crops to permanent crops and uncertainty about water deliveries from the Sacramento-San Joaquin Delta, the heart of California’s elaborate surface water conveyance system finding.Lower groundwater levels have significantly increased pumping costs and increased the need for constructing deeper wells where existing wells were not sufficiently deep to access falling water levels finding. Greater reliance on groundwater during the drought has caused land subsidence on a large scale in the Central Valley finding, coastal basins and Southern California; it has also exacerbated seawater intrusion where pumping occurs in aquifers near the coast finding. As pumping lowers the water table, water quality is sometimes compromised by saline water or other naturally occurring contaminants finding. Rapidly falling water tables also lead to more-contaminated shallow groundwater entering drinking water wells. Agricultural regions in California are challenged not only by dwindling groundwater supplies — a critical drought insurance for California — but also by significant groundwater quality degradation, in particular from nitrate and salt pollution. Pollutants may come from urban sources finding,vertical farm system domestic household sources finding or agricultural sources finding.
A number of studies have shown a high incidence of nitrate, above drinking water standards, in domestic and public drinking water supply wells; in some counties, more than 40% of domestic wells exceed the nitrate limit for safe drinking water finding. Salt accumulation in streams and groundwater has also been found to be significant finding, with potentially punitive economic consequences: By 2030, the combined impact of surface water and groundwater salinization to agriculture and the California economy, if current conditions continue and no preventative action is taken, is estimated at $6 to $10 billion annually in lost production costs, job losses and other impacts finding. The problems of groundwater overdraft and water quality degradation have been recognized for some time. Increasing public concern over the past two decades has raised the level of local, state and federal government engagement and of actions by policy- and decision makers. Groundwater users and wastewater dischargers in the urban and the agricultural sectors face new regulatory requirements. While urban governments have a long history of dealing with limited water resources, the agricultural community is experiencing significant and historic changes in its involvement with managing groundwater extraction and protecting groundwater resources for the future. Based on these principles, the legislation lays out a framework for the entire state to manage its groundwater. In 127 medium- and high-priority groundwater basins finding, groundwater sustainability agencies finding will have to be formed no later than June 2017. These GSAs will be responsible for developing and implementing a groundwater sustainability plan finding that has specific objectives and meets specified sustainability targets consistent with the core principles of the SGMA. GSAs have 3 to 5 years to develop and begin implementing their GSP finding. GSAs must show significant progress in implementing their plan and achieve sustainability no later than 2042.Funding for GSP activities will likely come from a combination of state and local funding sources. In over drafted basins, adjudications may continue to be an alternative process to achieve sustainability, despite the high cost and often years-long legal proceedings involved. As of this writing, the Legislature is actively considering multiple bills that would create an alternative, streamlined adjudication process.
In the intermediate and long run, the main impact from this legislation will be that new recharge and groundwater storage options will be pursued, and, where needed, pumpers may see restrictions in pumping or well drilling. Where additional recharge is available, pumpers may be asked to pay additional costs to secure the recharge needed in return for their right to continue pumping. Basin boundaries may be adjusted and may include fractured rock aquifers currently not recognized as groundwater basins by the Department of Water Resources although they are subject to significant groundwater extraction in some areas. Litigation and state intervention may be inevitable in some cases, but it remains to be seen how frequently that route will be chosen over mediation or facilitated GSP development and implementation. In either case, the new groundwater legislation marks a turning point in California water management by no longer allowing for continued depletion of groundwater resources and by requiring an active, well-informed groundwater management system that is better integrated with surface water management, water quality management and land use decisions to maintain a balance that best serves competing human, economic and environmental health interests.The federal Clean Water Act addresses only surface water quality. By contrast, California’s water quality law, the Porter Cologne Water Quality Control Act of 1969 finding, includes the protection of groundwater quality. The California Legislature designated the State Water Resources Control Board finding and nine newly created regional water boards finding to implement the Porter-Cologne Act. The primary function of the RWBs is to establish a basin plan that identifies water quality goals and to develop regulatory programs to achieve those goals. Non-point sources of potential groundwater pollution finding were long exempted from direct oversight through unconditional waste discharge waivers. However, those waivers were discontinued by the Legislature in 2002, which led to new regulatory requirements for agricultural and other non-point source water dischargers finding. Focused on surface water quality in the first decade after 2002, these regulatory efforts now increasingly address groundwater quality. They require demonstrable source control and documentation of groundwater nitrate and salt discharges and also provide state and federal funds to improve the drinking water supplies of communities affected by poor groundwater quality.
The Central Valley RWB and Central Coast RWB regions are home to large areas of California’s most intensive agricultural operations and have therefore developed the most extensive regulations. But all RWBs are obligated to consider discharges from non-point sources to groundwater and to develop basin plan amendments for nutrient and salt management finding.The 2007 Dairy Order was the first comprehensive California groundwater quality permitting program applicable specifically to farms. It sets the framework for permitting dairy discharges of nutrients and salts to surface water and groundwater. The dairy order requires dairies to prepare nutrient and waste management plans, annually report nutrient budgets for individual fields, tonnage of manure exports and water quality of on-site wells. Targeted shallow groundwater monitoring and efforts to develop improved management practices that demonstrably improve groundwater quality are implemented through the Central Valley Dairy Representative Monitoring Program. This program is led by a coalition of dairy producers that is working closely with the RWB; it offers an efficient alternative to individual dairy groundwater monitoring plans.Upon its inception in the early 2000s, the Central Valley ILRP finding focused on surface water and watershed protection through farmer education, certification and coalition-led stream water quality monitoring and management. But since 2010, the Central Valley RWB has been expanding the ILRP to add elements that also protect and improve groundwater quality, primarily nitrate, pesticide and salt contamination, through source management on irrigated lands. In the Central Valley, the ILRP covers about 7 million irrigated acres with several tens of thousands of individual farms. Permits finding are given either to individual farms or to regional ILRP coalitions, organizations that farms can join to represent them collectively with the RWB. ILRP coalitions representing large groups of farmers include the Sacramento River Watershed, Rice Farmers, Eastern San Joaquin Watershed, San Joaquin County and Delta, Western San Joaquin Watershed, Tulare Lake Basin Area, and Western Tulare Lake Basin Area coalitions. Each coalition is subject to a separate RWB order. Under the expanded ILRP, the first step is a Groundwater Assessment Report finding, which is currently being developed or has been developed by each of the coalitions. The assessment identifies historic and current groundwater quality conditions and identifies vulnerable groundwater regions. The assessment provides the rationale for the monitoring and reporting requirements, which may differ within and between regions, and allows for a tiered program of monitoring and reporting requirements for sub-regions to reflect the diverse potential impacts to groundwater. In a next step, beginning in 2015, field specific nutrient management planning forms will need to be completed by all farmers for the first time. Generally, farmers will now be required to implement management practices, keep appropriate records finding and report some of the information collected to their coalition. The coalitions are further responsible for performing groundwater monitoring, typically in a network of domestic and monitoring wells. As in the dairy program,vertical indoor farming the coalitions are also responsible for developing management practices that demonstrably improve and protect groundwater quality. A significant focus will be on documenting field nitrogen inputs and outputs and on improving nitrogen-use efficiency.In 2012, the Central Coast RWB adopted an update to the ILRP, called the Agricultural Order finding. The program covers about 4,000 farms on about 400,000 acres. Based on its own groundwater assessment work, the RWB created three tiers of farms depending on the potential risk they pose to groundwater quality. The tiers are determined by pesticide use, farm size, nitrate occurrence in nearby public supply and farm wells, and by crop type.
About one in seven farms are in the highest tier, tier three finding, about half of the farms, mostly vineyards, fall in the lowest tier finding, and the remainder are in tier two. As in the Central Valley, farms in all tiers are required to perform proper nutrient, pesticide and irrigation management, documented in their farm plans finding. Back flow prevention and proper well abandonment are also required on all farms. Unlike in the Central Valley ILRP, all farms need to sample groundwater from existing wells twice during the first year. Subsequent groundwater sampling frequency is greater for farms in tier three than in tier two or one. Farms can choose to implement the groundwater sampling program individually or join a coalition that has been created specifically to perform groundwater monitoring and to support farmers with the implementation of the Agricultural Regulatory Program.Operating at an even larger scale and affecting stakeholders beyond agriculture finding is the Central Valley Salinity Alternatives for Long-Term Sustainability finding program. In coordination with the RWB, it was created in 2009 by stakeholders to develop a comprehensive salt and nutrient basin plan amendment for the Central Valley that complies with the state’s recycled water policy finding. The development of the basin plan amendment includes a wide range of assessments by CV-SALTS: nitrate and salt source loading from agricultural, urban and industrial sources, extensive review of surface water and groundwater quality data, and development of potential management practice and infrastructure solutions. The CV-SALTS program builds upon and is coordinated with the Central Valley Dairy Order and ILRP efforts. It focuses in particular on avoiding future salinization of the Central Valley aquifer system under SWRCB’s overarching antidegradation policy. Stakeholders are organized within the Central Valley Salinity Coalition finding, which is scheduled to provide its final salt and nutrient management plan finding to the RWB in 2016. As part of these efforts, a recent Strategic Salt Accumulation and Transport Study finding compared historic water quality data to an assessment of current salt and nutrient loading in the Central Valley; it determined that approximately 1.2 million acre-feet of Central Valley groundwater needs to be desalinized annually to meet long-term irrigation and drinking water standards. SSALTS suggests various alternatives for water treatment, including desalination and evaporation ponds. Implementation costs are estimated to be roughly $70 billion over the next 30 years, of which $20 billion can be raised by selling approximately 1.1 million acrefeet of ultra clean treated water annually to urban areas. These costs include some saline water being disposed of by deep injection and some being stored in salt accumulation areas on the Tulare Lake Bed finding.