1. (1) The applicant shall provide lot layout documents for the subdivision application. At least one copy of the lot layout must be submitted with the subdivision application. Prior to final approval, four copies of the final lot layout must be submitted. The lot layout documents must be on sheets no larger than 11" x 17", at a scale no smaller than 1" = 200'. The reviewing authority may require a larger scale if needed to enhance readability. Multiple sheets may be used for large developments, provided that individual lots are not split across two sheets. If multiple sheets are used, a single sheet must also be provided, using an appropriate scale, that shows the entire development.

2. (2) The following information must be provided on the lot layout documents. Other information (e.g., percolation test results, soil profile descriptions) may be included on the lot layout documents only if the documents remain legible:

   1. (a) the name of the subdivision, and the county, section, township and range (e.g., "Sec. 12 T27N R6E") in which the subdivision is located;
   2. (b) a north arrow and scale;
   3. (c) the boundaries, dimensions, and total area of each lot;
   4. (d) an identifier or number for each lot (e.g., "Lot 1, Lot 2," "Tract 1, Tract 2," or "Parcel 1, Parcel 2");
   5. (e) locations of existing and proposed easements;
   6. (f) locations of existing and proposed roads and utilities;
   7. (g) locations of drainageways;
   8. (h) name and affiliation of the person who prepared the lot layout;

   9. (i) information as set out in Table 1 for the specific water supply, wastewater, and storm water facilities in the subdivision, and those located within 100 feet of the perimeter of the subdivision or parcel. All systems must be labeled as "existing" or "proposed." For individual and shared systems, the locations and design details do not have to be shown on the lot layout if those details will not be determined until the time of septic permitting.

      TABLE 1

      REQUIREMENTS FOR LOT LAYOUTS

      	Subdivisions served by nonmunicipal wells	Subdivisions served by nonmunicipal wastewater systems	Subdivisions served by municipal water or municipal sewer systems
      Existing wells and proposed well locations or approved drilling areas, setbacks in ARM 17.36.323 Table 2, and features listed in ARM 17.36.103(1)(d) within 100 feet of the subdivision	X	X	X
      Water lines (suction and pressure)			X
      Water lines (extension and connections)	X	X	X
      Existing and proposed wastewater systems (drainfield, replacement area, and existing septic tanks)	X	X
      Existing and proposed gray water irrigation systems	X	X	X
      Percent and direction of slope across the drainfield	X	X
      Sewer lines (extensions and connections)	X	X	X
      Lakes, springs, irrigation ditches, wetlands and streams	X	X
      Percolation test locations, if provided, keyed to result form		X
      Soil pit locations keyed to soil profile descriptions		X
      Ground water monitoring wells keyed to monitoring results form	X	X	X
      Floodplain boundaries	X	X	X
      Cisterns	X	X	X
      Existing and proposed building locations	X	X	X
      Driveways	X	X	X
      Road cuts and escarpments or slopes > 25%		X
      Mixing zone boundaries and direction of ground water flow	X	X
      Locations, sizes, and design details of proposed storm water facilities	X	X	X
      Locations and sizes of existing storm water facilities	X	X	X

Authorizing statute(s): 76-4-104, MCA

Implementing statute(s): 76-4-104, 76-4-125, MCA

History: Eff. 12/31/72; AMD, Eff. 11/4/73; AMD, Eff. 11/3/75; AMD, Eff. 5/6/76; AMD, 1977 MAR p. 746, Eff. 10/25/77; AMD, 1984 MAR p. 1027, Eff. 7/13/84; AMD, 1992 MAR p. 2145, Eff. 9/25/92; TRANS, from DHES, 1996 MAR p. 1499; AMD, 2002 MAR p. 1465, Eff. 5/17/02; AMD, 2009 MAR p. 1786, Eff. 10/16/09; AMD, 2014 MAR p. 2098, Eff. 9/19/14; AMD, 2023 MAR p. 324, Eff. 4/15/23.