Groundwater, combined with a climate that allows for year-round cultivation, turned the region into a horn of plenty. Groundwater built the region into an agricultural powerhouse. But, in a tragic twist, the farmers drank too deeply. They used more groundwater than the basin could sustain. In Monterey County, the salt water boundary, at its farthest reach, is more than 10 kilometers 6 miles inland. Each of the basins must eventually put tighter controls on groundwater consumption, thanks to a landmark state law that was signed last year.
Many managers in the region believe that the drought will worsen the saltwater intrusion problem, which had largely been halted before , because there is little rainfall to replenish the aquifers and in many areas groundwater pumping has increased. Groundwater levels are 1 meter 3 feet lower in the uppermost aquifer of the Salinas Valley, compared to , according to the Monterey County Water Resources Agency.
That is an open door for salt water. Water managers are not sure how far the salt front has advanced. Monitoring reports for will be published next winter and spring. Managers have heard stories of wells going sour and farmers drilling deeper for water, so they suspect that the salt boundary will shift.
Seawater, however, moves slowly and the full effect of the current drought will not be known for several years, according to Brian Lockwood, hydrologist for Pajaro Valley Water Management Agency. Managers expect that the drought will not be as great a problem as it could have been because of actions and collaborations that the water districts took years ago. A kilometer mile purple pipe system delivers recycled water from Watsonville, California, to farmers in the Pajaro Valley, some of the most lucrative farmland in the state.
Pajaro Valley Water Management Agency, for instance, worked with the city of Watsonville to provide farmers with an alternative to groundwater. In , the two entities opened a facility that purifies city water for use in the fields. A kilometer mile network of purple pipes carries the recycled water to growers along the coast. Opened in , the Castroville facility provides irrigation water to 4, hectares 12, acres in the Salinas Valley.
Lose the valley? Seawater intrusion in the Salinas Valley had stopped in because of investments such as the Castroville facility. In Monterey County, a new water recycling system is completing a design review. By , the facility will produce 3, acre-feet of recycled water from industrial wastewater, farm drainage, and stormwater, for injection into the aquifer and for farm irrigation. The district recently finished relocating its second well. The district also began a year-long study in July to assess the feasibility of injecting recycled water into the aquifer, to reinforce the freshwater barrier against the Pacific.
Brett writes about agriculture, energy, infrastructure, and the politics and economics of water in the United States. He is the winner of two Society of Environmental Journalists reporting awards, one of the top honors in American environmental journalism: first place for explanatory reporting for a series on septic system pollution in the United States and third place for beat reporting in a small market Brett lives in Seattle, where he hikes the mountains and bakes pies.
Contact Brett Walton. Pretty good story up until the last paragraph BS. You know the climate is not actually causing the drought.
This article contains an error, a misstatement. You might also note that Pajarro Vslley water agency tried in the late 90s to secure water contracts and transferable water from the CVP and CVP contractors, However those efforts failed — there simply was not and is not enough CVP export water to go around. This is nothing new.
The over pumping from the Coastal Aquifers has made it a problem for decades. Combination byproducts, resulting from the interactions between contaminants in treatment storage and pipes, add another dimension of troubling chemistry to the recycled soup.
Failure to address these problems might well be the death knell for successful agriculture in this region. This site uses cookies. By continuing to browse the site, you are agreeing to our use of cookies. We may request cookies to be set on your device. We use cookies to let us know when you visit our websites, how you interact with us, to enrich your user experience, and to customize your relationship with our website. Click on the different category headings to find out more.
Saltwater intrusion affects ground-water stock negatively and, in extreme cases, results in the abandonment of supply wells when dissolved ion levels exceed drinking-water standards.
Several other case studies can be found here. Several city planning departments have been taking proactive measures to track salinity levels in the drinking water supply. A common approach to reducing saltwater intrusion has been to reduce the rate of ground-water pumping from coastal supply wells or to move the locations of pumping further inland.
Reduced coastal extractions allow ground-water levels to recover from their stressed levels, and allow space for fresh ground-water to displace the intruded saltwater. In some states like New Jersey, reductions in ground-water withdrawals in some coastal counties due to a State mandate have resulted in ground-water-level increases in aquifers that have been affected by saltwater intrusion.
There have also been efforts to artificially recharge freshwater into an aquifer to increase ground-water levels and control the hydraulic movement of the invading saltwater. Specially designed Injection wells or by infiltration of freshwater at the land surface are used to accomplish artificial recharge 7. The most noticeable example of the use of artificial recharge in the United States is in southeastern Florida. In that area, a widespread network of surface-water canals is used to transport fresh water from inland water-storage locations during the dry season to coastal regions, where the water is recharged through the canals to the underlying aquifer to slow saltwater intrusion in the aquifer.
In addition to conventional methods, scientific and innovative strategies are now being used to control or manage saltwater intrusion along the Atlantic coast. These include aquifer storage and recovery systems and desalination systems. Aquifer storage and recovery ASR is a process by which water is recharged through wells into a suitable aquifer, stored for a duration, and then extracted from the same wells when needed 8.
High concentration of chlorine has bad effects on the environment as well: it can produce leaf burn and even defoliation in sensitive crops; in lakes can increase the presence of metals in waters and prevent the distribution of oxygen and nutrients and thus harm aquatic life.
Click here for general information about groundwater contaminants. Check also nitrates , arsenic and iron in groundwater. For more information check the following pages: groundwater contamination , quality , source of groundwater pollution , reducing groundwater contamination.
Click here for definitions concerning groundwater, or to learn more about its properties , its origin and quantities , its sources in Europe. Toggle navigation. Seawater intrusions in groundwater Seawater intrusion is the movement of seawater into fresh water aquifers due to natural processes or human activities.
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