Setback Distances

310 CMR: Department of Environmental Protection
Please check the Hingham Board of Health Supplementary Rules and Regulations (PDF) located on this website for Setback Distances which may be greater than those listed below

15.211: Minimum Setback Distances
All systems must conform to the minimum setback distance for septic tanks and soil absorption systems, including reserve area, measured in feet and as set forth below. Where more than 1 setback applies, all setback requirements shall be satisfied.

Septic Tank Soil Absorption System
Property Line 10 10
Cellar Wall or Swimming Pool (in ground) 10 20
Slab Foundation 10 10
Water Supply Line (pressure) 10[1] 10[1]
Surface Waters (except wetlands) 25 50
Bordering Vegetated Wetland (BVW), Salt Marshes, Inland and Coastal Banks 25 50
Surface Water Supply - Reservoirs and Impoundments 400 400
Tributaries to Surface Water Supplies 200 200
Wetlands Bordering Surface Water Supply or Tributary Thereto 100 100
Certified Vernal Pools 50 100[2]
Private Water Supply Well or Suction Line 50 100
Public Water Supply Well (2) (2)
Irrigation Well 10 25
Open, Surface or Subsurface Drains which 50 100
Discharge to Surface Water Supplies or Tributaries Thereto Other Open, Surface or Subsurface Drains
(excluding foundation drains) which intercept seasonal high groundwater table [3]
25 50
Other Open, Surface or Subsurface Drains
(excluding foundation drains)
5 10
Leaching Catch Basins and Dry Wells 10 25
Downhill Slope not applicable 15[4]

Additional Details
[1] Disposal facilities shall also be at least 18 inches below water supply lines. Wherever sewer lines must cross water supply lines, both pipes shall be constructed of class 150-pressure pipe and shall be pressure tested to assure water tightness.

[2] The required setback shall be 50 feet where the applicant has provided hydrogeologic data acceptable to the approving authority demonstrating that the location of the soil absorption system is hydraulically down gradient of the vernal pool. Surface topography alone is not determinative.

[4] The setback distance shall be measured from a naturally-occurring downhill slope which is not steeper than 3:1 (horizontal:vertical). A minimum 15-foot horizontal separation distance shall be provided between the top of the peastone in the soil absorption system and the adjacent downhill slope. For a system located in an area with any adjacent naturally occurring downhill slope steeper than 3:1, slope stabilization shall be provided in accordance with best engineering practice which may include construction of a concrete retaining wall constructed in accordance with 310 CMR 15.255(2).

(2) No system shall be constructed within a Zone I of a public water supply well or wellfield. No system shall be upgraded or expanded within a Zone I of a public water supply well or wellfield unless a variance is granted pursuant to 310 CMR 15.410 through 15.415.

March 24, 1995 (Effective March 31, 1995) 310 CMR - 512