Pond Boss Forums INTRO Questions & Observations Water loss

This is a question about natural water loss during the summer I have a pond in the Calif. Sierra foothills, 5 surface acres filled with winter rain runoff and springs, supplimented with well water in the summer, no outflow. There is a new 22 foot dam containing much clay, as well as a good clay base on the pond bottom. During the summer, with an average daily temperature of about 90 degrees, the pond is dropping about a foot a month, without any well water added. This seems excessive, but maybe not.
Anybody out there know? Thanks

Frank, that loss appears normal to me. I am in a similar though drier climate near Ukiah. I lose about 7 feet of water during the dry season. This is comparable to other ponds in the area so I know I am not leaking. My pond is 20 years old, so it is well established.

Jim in Ukiah. Thanks for the info. I feel better about the evaporation rate of my pond, knowing yours is about the same. You won't believe how much water loss there is daily during the summer on a 5 acre pond - about 80,000 gallons. This calculation can be made knowing the average monthly drop and the water surface area. The unknown is perculation.

Frank, I never have calculated my daily evap rate. I have a 2 acre pond with a capacity of 15 acre feet when full. I'm guessing that I lose about half that during the season or about 2.5 million gallons in total. I wish I could keep more of the winter runoff!

What is the annual precipitation in the area of your ponds?

Bill, annual precipitation does not have much relevance here since we typically have no rain, repeat no rain from April or May until October or November depending on the year. Having said that, our average annual rainfall here (125 miles north of San Francisco) is about 40 inches. Each year we watch all standing bodies of water recede and hope the rains will come.

Bill Cody: The precipitation rate in my area of Northern California, 2700' elevation is 40-50 inches a year. My pond is 5 surface acres. Presently I am adding approximately 30,000 gallons per day of well water, and the level is staying abouteven, Daily high temperatures, about 55-60 degrees, nights, about 35 degrees