Jeff Cattaneo, District Manager/Engineer for the San Benito County Water District (SBCWD), yesterday confirmed that to date existing oil/gas wells in San Benito County have not caused pollution or contamination of groundwater in San Benito County. He said that the SBCWD Board of Directors are monitoring the energy extraction ban proposed by San Benito Rising and are waiting until the appropriate time to issue a statement as to the accuracy and veracity of the environmental activist group’s claims with respect to “poisoning our water”, a statement made by San Benito Rising members to the voting public.
In 1953, the State Legislation passed legislation establishing the District Act, forming the San Benito County Water Conservation and Flood Control District (which succeeded the Hollister Irrigation District that was formed in 1922). In 1989, the District changed names, and officially became how it is known today, the San Benito County Water District.
In 1957, the financing for building and operating Hernandez Dam, and the reconstruction of the Paicines Canal and Diversion works were approved. In 1977, voters in San Benito County voted with 82% approval to fund the project to implement and import water into the County. In 1978, the San Benito County Water Conservation and Flood Control entered into a contract with the U.S. Bureau of Reclamation to finance the project and act as the delivering agency for the contracted 43,800 acre feet of imported water. Contracts were awarded in 1982 to start construction on San Benito’s own distribution system to deliver the imported water. The distribution system is comprised of eight pressure reducing turnouts, four pumping facilities, eleven percolation sites, and the 10,000 acre foot San Justo Reservoir. A computerized telemetry system aids in delivering water through over 120 miles of buried pipe.
Today, the District manages the groundwater in the San Benito County portion of the Hollister-Gilroy basin, operates the San Benito River System and the San Felipe Distribution System, delivers imported CVP water to irrigation and M&I customers, and manages recharge through local streams. The District is governed by an elected five member Board of Directors, and administered by the District Manager/Engineer.
Many farmers and ranchers benefit from the imported water because the purchased water is superior in quality to groundwater pumped from local aquifers and is more conducive to crop growth. Local groundwater has varying levels of salts, high mineral content, Total Dissolved Solids (TDS) and constituents like boron which at certain residual quantities ( or at thresholds of parts per million parts of water) are toxic to some crops.
The toxicity problem
Apart from the salinity or the sodicity hazard, the constituents of much irrigation water may cause toxicity problems when taken up by the plants in excess amounts. The toxic constituents of major concern are sodium, chloride and boron. Fruit trees, vines and woody ornamentals are especially sensitive to sodium and chloride ions. Most annual crops are not so sensitive but may be affected by higher concentrations. Sodium and chloride ions are freely taken up by the plants and become concentrated as water is lost through transpiration. Toxicity results when the concentration of these elements exceeds the tolerance limits of the plants. ‘Leaf burn’ scorch, and dead tissue along the outside edges of leaves are typical symptoms of sodium toxicity which first occur in the oldest leaves, usually appearing as a burn or drying of tissue at the outer edges of the leaf. As the severity increases, the drying progresses towards the leaf centre until the entire tissue is dead. Injury due to chloride toxicity however, typically, starts at the extreme leaf tip of older leaves and progresses from the tip back as the severity increases.
A slight excess of boron in the irrigation water or in the soil solution can cause toxicity to a variety of crops. Boron is taken up by the crop and is accumulated. For example, as little as 0.6 mg elemental boron per litre in the irrigation water may produce toxicity symptoms in citrus leaves; 1 mg/l may reduce the yields of citrus and certain stone fruits and 4 mg/l is harmful to many crops.
The SBCWD manages the local watershed and consults with technical specialists with expertise in water quality and water treatment methodologies to maximize local water quality to its agricultural, municipal and industrial customers. Thus, we can expect the SBCWD Board of Directors and General Manager/Engineer to carefully evaluate the claims of San Benito Rising and make a pronouncement regarding the relative risk of energy extraction technologies in San Benito County, especially with the advent of Senate Bill 4, signed by Governor Brown late last year, which regulates hydraulic fracturing practices and provides the strictest environmental safeguards in the United States.