I'm involved in a project installing a large residential RO system and associated pre-treatment equipment in a newly constructed outbuilding. Contractor did not install a drain during building construction. Drain will run into a county ditch 55' from the building. Have 0.25"/ft fall from building to ditch. Flow shouldn't be over 15 GPM normally but drain should be sized to handle accidental backwashes from 2 filters at the same time (30 GPM). Current plant is to run 4" in the ground.
Can we transition to 3" out of the ground, sanitary tee, and a single 3" trap/standpipe inside building?
Are we "safer" with two traps?
I'm assuming the only feasible option at this point is a vent from santee up the exterior of building to under the soffit? If so, can we downsize the vent?
Not in city jurisdiction.
Appreciate any guidance.
Can we transition to 3" out of the ground, sanitary tee, and a single 3" trap/standpipe inside building?
Are we "safer" with two traps?
I'm assuming the only feasible option at this point is a vent from santee up the exterior of building to under the soffit? If so, can we downsize the vent?
Not in city jurisdiction.
Appreciate any guidance.
