Developers shall be required, as a condition for approval of a subdivision or site plan, to pay their pro rata share of the cost of providing reasonable and necessary street improvements and water, sewerage and drainage facilities and easements therefor located outside the property limits of the subdivision but necessitated or required by construction or improvements within said subdivision. The following criteria shall be utilized in determining a developer's proportionate or pro rata share of necessary off-tract improvements.
In cases where the reasonable and necessary need for an off-tract improvement or improvements is necessitated or required by the proposed development application and where no other property owners receive a special benefit thereby, the applicant may be required, as a condition of approval, at the applicant's sole expense, to provide for and construct such improvements as if such were an on-tract improvement in the manner provided hereinafter and otherwise provided by law.
In cases where the need for any off-tract improvement is necessitated by the proposed development application and where it is determined that properties outside the development will also be benefited by the improvement, the following criteria shall be utilized in determining the developer's proportionate share of such improvements:
A. 
Sanitary Sewers. For collection facilities, including the installation, relocation or replacement of collector, trunk and interceptor sewers and the installation, relocation or replacement of other appurtenances associated herewith, the applicant's proportionate share shall be computed as follows:
(1) 
The capacity and design of the sanitary sewer system shall be based on Rules and Regulations for the Preparation and Submission for Sewerage Systems, New Jersey Department of Environmental Protection, and all Alexandria Township sewer design standards, including infiltration standards.
(2) 
Developer's pro rata share.
(a) 
The capacity of the existing system to serve the entire sewerage area shall be computed. If the system is able to carry the total developed sewerage area, no improvement or enlargement cost will be assigned to the developer. If the existing system does not have adequate capacity for the total developed sewerage area, the prorated enlargement or improvement share shall be computed as follows:
Total enlargement cost
or improvement cost
=
Total tributary gallons per day
Developer's cost
Developer's gallons per day
(b) 
If it is necessary to construct a new system in order to developer the subdivision, the prorated enlargement share to the developer shall be computed as follows:
Total tributary gallons per day
Total project cost
=
to new system
Developer's cost
Development tributary gallons per day
(c) 
The plans for the improved system or extended system shall be prepared by the developer's engineer. All work shall be calculated by the developer and approved by the Township Engineer.
B. 
Roadways. For street widening, alignment, channelization of intersections, construction of barriers, new or improved traffic signalization, signs, curbs, sidewalks, trees, utility improvement uncovered elsewhere, the construction or reconstruction of new or existing streets and other associated streets or traffic improvements, the applicant's proportionate cost shall be determined as follows:
(1) 
The applicant's engineer shall provide Township's engineer with the existing and anticipated peak-hour flows for the off-tract improvement.
(2) 
The applicant shall furnish a plan for the proposed off-tract improvements, which shall include the estimated peak-hour traffic generated by the generated by the proposed development. The ratio of the peak-hour generated by the proposed development to the future peak-hour traffic shall form the basis of the proportionate share. The prorated share shall be computed as follows:
Total cost of the
roadway improvement
and/or extension
=
Future peak-hour traffic
Developer's cost
Future peak-hour traffic
generated by the development
(3) 
The ratio thus calculated shall be increased by 10% for contingencies.
C. 
Drainage improvements. For stormwater and drainage improvements, including the installation, relocation or replacement of storm drains, culverts, catch basins, manholes, riprap or improved drainage ditches, or stormwater detention basin facilities and appurtenances thereto and the relocation or replacement of other storm drainage facilities or appurtenances associated therewith, the applicant's proportionate share shall be determined as follows:
(1) 
The capacity and design of the drainage system to accommodate stormwater runoff shall be based on a method described in Urban Hydrology for Small Watersheds Technical Release 55, Soil Conservation Service, USDA, June, 1986, and shall be computed by the developer's engineer and approved by the Township Engineer.
(2) 
The capacity of the enlarged, extended or improved system required for the subdivision and areas outside of the developer's tributary to the drainage system shall be determined by the developer's engineer, subject to approval by the Township Engineer. The plans for the improved system shall be prepared by the developer's engineer and the estimated cost of the enlarged system calculated by the Township Engineer. The prorated share for the proposed improvement shall be computed as follows:
Total enlargement or improvement
cost of drainage facilities
Total tributary cfs
Developer's cost
=
Development cfs
Where the proposed off-tract improvement is to be undertaken at some future date, the moneys required for the improvements shall be deposited to the credit of the Township in a separate account until such time as the improvement is constructed. If the off-tract improvement is not begun within 10 years of deposit, all moneys and interest shall be returned to the applicant.
In any case in which an applicant shall not provide the approving authority with the estimates of a traffic calculation and/or consulting engineer with regard to estimated improvement costs and all other information necessary to proportion costs, the approving authority may rely on the estimates of the Township Engineer in order to prorate costs.