Something in the water

It doesn't take much to contaminate a water supply.

POULSBO -- E. coli found in a water system here was likely caused by a drowned squirrel, according to officials. An order to boil water for those in the Indian Hills Estates water system was imposed last weekend after routine water testing found the E. coli bacteria, Kitsap County Public Utility District officials said.

According to the Kitsap County Public Utility District, Indian Hills Estates has all of 48 service connections, and the ability to store 31,700 gallons of water. That's equivalent to one small tank. In fact, that volume of water would fit in a cube a little over 16 feet on a side. One small animal can easily generate enough bacteria to contaminate that volume of water.

Once it's contaminated, the solution is to chlorinate the living daylights out of it, or to empty it out and clean it, then re-fill.

One advantage of increased security since September 11, 2001 is that the LA DWP has increased the frequency with which our water tanks are checked. We used to pull a sample once a month, or once a quarter for smaller tanks. Now it's once a week for all tanks.

One time, when I was training a new employee, the sample point we were supposed to pull water from was down for water main work. I called in to the office and was given an alternate point.

It turned out to be the wrong alternate – it didn't draw from the same pressure zone. However, it had no detectable chlorine in the water. A quick investigation showed that the tank supplying water to that area had no chlorine. A bird had gotten through the vent screens on the tank and drowned in the water. One sparrow was enough to use up all the chlorine in that tank.

On that occasion, it was good luck that found the problem before we started seeing bacteria. Now, it's because we check tanks too frequently to give that sort of thing time to become a problem.