For a complete explanation of the following criteria, please refer to the DEP draft guidance:


Sewage Facilities Planning Module Review for Onlot Sewage Systems Proposed in High Quality and Exceptional Value Watersheds (PDF)


The Wayne County Planning Department graciously provided the following summary:


The Pennsylvania Department of Environmental Protection is proposing new regulations (called "guidance") that will seriously increase the difficulty and cost of the installation of sub-surface sewage systems in all special protection watersheds (high quality and exceptional value).


When proposing a new sewage system, or a replacement, the applicant must accumulate a protection factor of 45 points through a system based on Best Management Practices (BMPs) qualifiers such as: lot size, setbacks, buffers, de-nitrification technology and/or a permeable reactive barrier. In summary form, here are the basics of each:


Lot size- if the 45 points are to be achieved by lot size only, the average lot size must be 11.25 acres. A protection factor of 4 is assigned for an average lots size of 1 acre per EDU. Using DEP's method found in the new regulations, (11.25 acres X 1 EDU) X 4 = 45. This is the only BMP in itself where an applicant could acquire the 45 points needed. If the average lot size is less than 11.25 acres, one or more of the following BMP's would be required.


Setback distance from the edge of the absorption field to the surface water would yield the following points:


Under 200 feet1
200-1,000 feet2
1,000+ feet4


Land area assigned and used as a riparian buffer or riparian forest buffer should not also be assigned as a setback distance. Only the distance beyond the buffer should be counted towards a setback distance.


Vegetative riparian or forested riparian buffers can be used in combination with other qualifiers, but a Declaration of Environmental Covenant with the DEP would need to be filed in the County Register and Recorder's Office particularly limiting the use of land in the buffers. Points acquired by vegetative or forested buffers would yield the following points.


BuffersVegetative Riparian PointsForested Riparian Points
50-99 feet1.52
100-149 feet23.33
150+ feet3.3310



De-nitrification technology would be additional devices added to the sewage system. Estimates in cost range from $3,500 - $7,000 (DEP estimate) to $9,500 (manufacturer's estimate) plus $300 per year operation and maintenance costs. This investment would yield 2 points.


Permeable Reactive Barrier- a trench at least 50 feet from absorption area, at least 2 feet wide, to a depth at least 2 feet below the seasonal low water table. The trench would be composed of pH-stabilized carbon source such as wood chips and/or sawdust. Cost- estimated to be $5,000 to $15,000. Such a trench would yield 4 points.


UPDATE: Prompton Borough Letter to DEP Opposing Draft Guidance

Onlot System Density
4 Total Acreage:
Total Number of Dwellings:
Setback Distance
1 Under 200 feet
200 - 1000 feet
More than 1000 feet
Riparian Forest Buffer
1 Under 50 feet
50 feet up to 100 feet
100 feet up to 150 feet
150 feet or more
Riparian Buffer
1 Under 50 feet
50 feet up to 100 feet
100 feet up to 150 feet
150 feet or more
Permeable Reactive Barrier
1 No barrier
Permeable Reactive Barrier installed
De-nitrifying Technology
1 Not in use
De-nitrifying technology in use
Application Result