Lagoon Site Location Fact Sheet
This guidance document is advisory in nature but is binding on an agency until amended by such agency. A guidance document does not include internal procedural documents that only affect the internal operations of the agency and does not impose additional requirements or penalties on regulated parties or include confidential information or rules and regulations made in accordance with the Administrative Procedure Act. If you believe that this guidance document imposes additional requirements or penalties on regulated parties, you may request a review of the document.

Form #:  12-028
Guidance Documents
Revised: 11/22/16


The installation of a lagoon is prohibited within the following horizontal setback distances (Table 5.2 of Title 124 - Rules and Regulations for the Design, Operation, and Maintenance of Onsite Wastewater Treatment Systems) unless individually reviewed and a construction permit is issued by the Department. The setback distance is the horizontal distance measured from the high water mark for the maximum operating depth of the lagoon. However, in no case shall a lagoon be installed in a location that results in any listed item being located closer than 10 feet horizontally out from the outer toe of a lagoon dike.

Lagoon Setbacks

Item
Minimum Setback Distance
Feet (meters)
Surface Water: Distance from High Water Mark
50 ft. (15.2 m)
Private Drinking Water Wells
100 ft. (30.5 m)
Public Drinking Water Supply Wells:

Non-Community
100 ft. (30.5 m)
Community
Evaluated by a professional engineer for potential impact on the well and submitted to the Department for approval if less than 1000 ft (304.8 m).
All Other Water Wells
100 ft. (152.4 m)
Water Lines:

Pressure-Main
25 ft. (7.6 m)
Pressure-Service Connection
25 ft. (7.6 m)
Suction Line
100 ft. (30.5 m)
Property Lines
50 ft. (15.2 m)
Trees and Brush
50 ft. (15.2 m)
Foundations

Except Neighbor’s Foundation:

Class 1
100 ft. (30.5 m)
Class 2
100 ft. (30.5 m)
Class 3
50 ft. (15.2 m)
Neighbor’s Foundation:

Class 1
200 ft. (61.0 m)
Class 2
200 ft. (61.0 m)
Class 3
100 ft. (30.5 m)

Note: For setback purposes, foundation classes are defined as follows:
  • Class 1 Foundation means a basement, a non-basement footing, or slab-on-grade living quarters where any portion of the living quarters basement, footing, or slab is lower in elevation than the onsite wastewater treatment system component.
  • Class 2 Foundation means a non-basement footing foundation, trailer house, or slab-on-grade living quarters higher in elevation than the on-site wastewater treatment system. Any other foundation that is not a Class 1 or Class 3 is a Class 2 Foundation.
  • Class 3 Foundation means slab-on-grade construction that is not used as living quarters.