Wastewater Treatment System Setbacks

Minimum required distances for placing components of a wastewater treatment system (septic system). This list is part of the Story County Code of Ordinance Chapter 65 "Private Sewage Disposal Systems" and may be found here. 

 
Minimum distance in feet from:
  Septic tank (1)
 Secondary Treatment (2)
Private water supply well 50 100
Public water supply well 200 200
Groundwater heat pump borehole 50 100
Lake or reservoir 50 100
Stream (Class A1, A2, and A3)  or pond 25 50
Edge of drainage district ditch 25 50
Edge of road ditch 10 10
Dwelling or other structure 10 10
Property lines (unless a mutual easement is signed and recorded 10 10
Other type of subsurface treatment system 5 10
Water lines continually under pressure 10 10
Suction water lines 50 100
Foundation drains 10 10
Subsurface drainage tiles 25 50

(1) Includes septic tanks, mechanical aeration tanks and impervious vault toilets.
(2) Includes subsurface absorption systems, mound systems, intermittent sand filters, constructed wetlands or waste stabilization ponds.