|our 3,000 gallon cistern|
Last weekend, thanks to Rachel Kamman and Mike Millsap, our 3,000 gallon cistern was moved to our garden. Rachel is with KHE a hydrology and engineering firm and Mike is with Millsap, Degnan & Associates, a general contractor. Thank you Rachel & Mike! And thanks to Gary, April, & Rachel we built the cistern’s 10' wide and 6” deep foundation so that we could bring it to a new home.
The cistern will collect rain from the classroom buildings roofs and gutters. This process is called rain water harvesting. Our garden will only need about 4,000 gallons of water a year so that means we will be self sufficient by using this rainwater to water our garden.
My mom, April, did the water calculations and will create a worksheet so that students can understand how to calculate how much water is collected and how much water the garden needs. She said that just one of the classroom roof's has the potential to harvest over 20,000 gallons of water in one year. That means a lot of excess roof water will run off into the Miller Creek watershed as stormwater than what we can use to water our garden with.
I found out that our school in Lucas Valley, San Rafael, gets an average of 34.29 inches of rain per year.