Pleasanton residents who have unloaded their dishwashers recently have probably noticed a white film on glasses and other cookware. That's due to well water, according to the general manager of Zone 7 Water Agency.
Residents reported a noticeable coating on their dishes on the Weekly's online Town Square forum. Some thought it may be a problem with their dishwasher, but it appears the culprit is the well water.
Zone 7 supplies 80 percent of residents in the city with water. The other 20 percent receive water from city of Pleasanton wells.
A few reasons are attributed to the increase in pumping from wells. One is that this time of year, Zone 7 crews are performing regular maintenance on pumping stations, leading them to use more groundwater, or well water, in the interim. Normally, water is a blend of surface water and groundwater. Also court-ordered reductions in pumping from the Delta and a drought has led Zone 7 to use its well reserves.
Water that's pumped and distributed from underground storage tends to have more minerals in it, explained Zone 7 General Manager Jill Duerig.
"The groundwater, because it is harder, leaves more minerals and they show up as spots on dishes," she said.
Like many other area water agencies, Zone 7 has been hit hard by dry rainfall seasons and a court-ordered pump reduction at the San Joaquin-Sacramento River Delta. In a normal year, the wholesaler averages about 80 percent of its supply from the Delta. But the State Water Project, which sells agencies water, has curtailed its allocations to Zone 7 to just 15 percent.
"When the State Water Project reduced its allocations, either because of drought or court decisions related to endangered species like the Delta smelt, then we have to make up the difference with well water, or groundwater," Duerig said.
The current weather forecast calls for up to seven consecutive days of rain here in the Bay Area and snow in the Sierras, but despite anticipated rainfall totals, it's a drop in the bucket for the situation the state is in.
"It's unlikely to have a huge impact because we're not just dealing with the natural conditions but also the court-driven decisions," Duerig said. "We aren't the ones making the decisions on how the allocations are determined. The California Department of Water Resources does that, and last we heard from them, they were thinking of dropping our allocation.
"My guess is that if they get enough rain and snow, they won't drop it, but 15 percent is still 15 percent," she added. "It's not a lot. It's much less than we would normally get this year."
Zone 7 has been asking residents to reduce water usage by 10 percent and will continue to do so.
One bright spot--pardon the pun--is that Zone 7 is nearing completion in a mineral processing plant on Hopyard Road, which is expected to help. The plant will remove some of the chalky-looking salts and minerals from underground drinking water supplies delivered primarily to the western side of its service area, in Pleasanton and Dublin. Groundwater will be pumped to the new facility for removal of minerals, such as calcium and magnesium, which, while not harmful to health, can leave buildup on plumbing fixtures.
The plant, which cost $39.5 million, is expected to open in June. It's being funded by water rates and connection fees on new development. A second plant of comparable size and cost, funded entirely by new development, is planned for 2014.
Household tips to combat hard water
* Leave a squeegee inside the shower and have each family member squeegee the walls and shower door after each use. This reduces hard-water buildup and a whole lot of scrubbing later on;
* Try applying plain white vinegar and lemon juice -- acids that help loosen and remove hard water deposits from glass shower enclosures;
* If your showerhead plugs up from hardness, fill a sandwich bag with vinegar and use a rubber band to fasten the bag to your shower. Leave it overnight;
* Pour a cup of white vinegar in the toilet bowl and leave it there overnight. Flush in the morning.
* Use phosphoric acid-based cleansers when cleaning the bathtub or shower. These items can be purchased at home improvement, drug or grocery stores. The manufacturer's instructions should always be followed.
For an artist's rendering of the Mocho Groundwater Demineralization Plant, click here
To view the Town Square forum on this topic with poster comments, click here