Little Yosemite Valley Composting Toilet Leach Field Installation

The toilet facility currently does not have a leach field. Approximately 800 gallons of sewage (liquid waste) is evaporated each year with an evaporator unit. The 1200 gallons that cannot be evaporated are transported out of the backcountry with pack animals. The evaporator requires more electrical power than the photovoltaic system can produce and power must be supplemented by a gasoline powered generator running 1- 2 hours per day. This project will install a leach field with two lines running parallel 30' long x 16" wide x 24" deep and five feet apart and five feet from the structure. There would be a 10' trench for the discharge pipe running from the structure to the leach lines with a valve box just outside the building.

The installation of the leach field would reduce stock use on the John Muir Trail by 72 mules per season, eliminate the daily generator use in a wilderness area, and reduce the maintenance requirements of the facility by 20 man days per year.