Pond Boss Forums INTRO Questions & Observations Runoff question

The simple math tells you the amount of water in inches or whatever units you're using, that's available for your pond. It's the maximum amount. To be precise, you have to account for any amount that recharges the aquifer underling the property, the amount that is absorbed by the soil and eventually evaporates, the amount that evaporates from the runoff before it reaches the pond, the amount that evaporates from the pond during the rain event, the amount that is transpired by vegetation, the amount consumed by the fauna and not returned to the watershed, the amount that leaks from the pond (the rate of leakage may be greater when the pond is higher, etc. The main effect of the vegetation is to slow the runoff, not stop it. In most places, it's the land's main protection against erosion. Most often, the toughest part is estimating the area of the watershed. Also, the reported rainfall may not be accurate for your property. Rainfall can vary a lot over a short distance. Your own rain gauge could help in trying to figure out what's going on. The water has to go someplace.