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Subdivision Review Program

The Department of Environmental Quality Subdivision Program reviews divisions of land comprising  less than 20 acres, as well as condominiums and recreational camping vehicle and mobile home parks, regardless of the size of the parcel where they are located.  This review under the sanitation in subdivisions regulations is limited to sanitation facilities, including the water supply, sewage disposal, solid waste disposal, and storm drainage systems.  Proper design and location of these facilities is necessary to protect the quality of water for public water supplies, domestic uses, and other beneficial uses, including uses related to agricultural, industry, recreation, and wildlife.

Subdivisions are reviewed prior to creating the parcels to assure that adequate sanitation facilities can be constructed, operated, and maintained to support each parcel. Planning ahead for proper design and location of the facilities helps protect both our surface and ground water in Montana.  Design manuals have been developed to provide standards for wastewater treatment systems, water supply development, and storm drainage systems. The regulations also set out minimum separation distances between water supply sources and potential contamination sources such as wastewater treatment systems, surface waters, and floodplains.
The regulations and subdivision review are structured to prevent pollution problems through the proper design, location, operation, and maintenance of sanitation facilities.

Official Rules are Effective Friday, September 19, 2014. 

17-358 pro-arm Subdivisions/On-site Subsurface Wastewater Treatment

17-358 adp-arm Subdivisions/On-site Subsurface Wastewater Treatment

Draft Working Rules

Official replacement pages will be published December 2014. Below is the notice of adoption and a draft working version. 

17-359 pro-arm Subdivisions/On-site Subsurface Wastewater Treatment (Public Water and Sewage System Requirements) 

17-359 adp-arm Subdivisions/On-site Subsurface Wastewater Treatment (Public Water and Sewage System Requirements)   

 Draft Subdivisions and Public Water Drainfield Rule

Types of Activities Regulated, Application Requirements, Permitting Procedures, Criteria, Fees, Additional Information

Septic Drainfield Soil Suitability Presentations

Pharmaceuticals, Personal Care Products, Endocrine Disruptors (PPCPs)and Microbial Indicators of Fecal Contamination in Ground Water in the Helena Valley, MT, USA --Presentation

Helena Valley Ground Water: Pharmaceuticals, Personal Care Products, Endocrine Disruptors PPCPs)and Microbial Indicators of Fecal Contamination--Manuscript