Tuesday, 19 June 2012 02:58

AWA study finds Camanche groundwater quantity is good, fault line may explain the quality issues

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Amador County – The Amador Water Agency Board of Directors last week heard results of a groundwater study in the Lake Camanche Water Improvement District Number 7, which said quantity is adequate, and quality issues may be explained by the discovery of a fault line between east and west sides of the area.

AWA General Manager Gene Mancebo said the report also came with bad news, as one of the main wells at Camanche is currently out of service due to a broken pump. He said the “good news is that there is plenty of groundwater in the region to meet the demand of current and future customers, even in dry years.”

Dunn Environmental president Pat Dunn presented the study Thursday, June 14, concluding that water quality is generally good, though over-drafting “can cause iron and manganese problems.” Water quantity is plentiful. Mancebo said the “20-year demand for the area is estimated at 917 acre feet per year, or only about 10% of available water supply, even after multiple dry years.”

He said the “biggest revelation came when Dunn described a previously unidentified fault line, and how the underground rock structures on the eastern side of the fault make water wells there much less productive than those on the western side.”

Lake Camanche Village is east of the fault and in the past, most wells had been drilled nearby, to reduce piping costs, Mancebo said. “Of the system’s current operating wells, only Well 9 is west of the critical fault line, and it has the highest capacity.”

With the new source information, Dunn “advised the Agency to depend on Well 9 for the majority of Camanche’s water supply, and to use restraint on the three eastern wells to keep them from developing water quality problems.” Dunn said “recent problems with Well 14 were caused by high usage.”

AWA Field Services Manager Chris McKeage advised the Board Thursday that Well 14 is currently out of service due to a broken pump, and the manufacturer is replacing it at no cost to AWA.

Dunn in the report recommended “redeveloping, or breaking up the fine material that can build up on the walls of a water well, to address water quality issues that have plagued Well 14 over the past few years.” McKeage said with the pump, motor and well column out of the well, “this would be an opportunity to do the redevelopment work recommended by Dunn.”

Since the work was not on Thursday’s agenda, directors asked for a special meeting as soon as possible to discuss options and costs to redevelop Well 14. A special meeting was called by the board president for 1:30 p.m. Tuesday, June 19 to consider the Well 14 work.

Story by Jim Reece This email address is being protected from spambots. You need JavaScript enabled to view it.