Greywater system - cost benefit analysis about stevens-lodge HOT 2 OPEN

Given that our only source of gray water are showers and bathroom sinks, can we add collecting rainwater/snowmelt from the roof into the gray water surge tank? That need to be one very beefy gutter! And another Stevens Lodge engineering feat!

from stevens-lodge.

Engineering would be necessary. Lets say that we installed a 2100 gallon cistern. By my envelope math, that's about 3 weekends of flushes without any replenishment. You'll get some replenishment from the sinks and showers, but yes, there's likely to still be a substantial deficit. Harvesting rainwater/snowmelt would work splendidly, especially since there's typically an abundance during the primary lodge occupancy period.

Harvesting it off the roof presents a lot of issues. Ones I can immediately think of:

• a filtering system to keep leaves, needles, and other detritus from entering the tank
• during mid-winter, the water coming off the roof is just above freezing. When it hits the gutters, which aren't heated, it will immediately refreeze. Now you have gutters that are functioning as ice dams. That would be very bad for the longevity of the roof.

Another idea: install a french drain on the downhill side of the lodge. It'll fill with water naturally as snow melts and trickles down through the gravel. In that french drain is a 4" pipe that leads back to the greywater tank. Have that water backfill into the greywater tank via gravity. Have another 4" pipe that handles the water in excess of filling the tank.

from stevens-lodge.