1.0 Apportionment of Benefit, Outlet Liability and Special Benefit
We have assessed that none of the works are associated with improvement or maintenance of privately-owned access structures. Therefore, all costs the works are assessed as Benefit and Outlet Liability.
We assess that the function of the Marentette-Mangin Drain is to provide drainage for local roadways and local development lands. Therefore, we assess that 50% of the cost of the works should be assessed as benefit, and that remaining 50% of the project costs should be assessed as outlet and injury liability.
2.0 Equivalent Area Method
Having due regard for the runoff generating potential of the road rights-of-way (accounting for the pavement, sidewalk and driveway areas) compared to the runoff generating potential of other lands within the watershed, we assess that roads should be assessed at a higher rate than residential lots and other lands. Based on our independent calculations we have adopted a multiplication factor of 2.0 for the roadways, 1.0 for residential lands, and 0.4 for open lands.
3.0 Overview of Assessment Calculation
STEP 1
The total project cost were first apportioned into benefit and outlet liability as follows:
Benefit = Estimated Cost x 0.5 = $174,438.66 x 0.5 = $87,219.33
Outlet = Estimated Cost x 0.5 = $174,438.66 x 0.5 = $87,219.33
STEP 2
The total calculated tributary land area of 49.4 ha was separated into highway, local roads, residential lands, and open land areas of 23.0 ha., 3.2 ha., 7.6 ha., and 15.6 ha., respectively. The subareas were factored by the multipliers noted above. An equivalent subareas and total area was calculated as follows:
Equivalent Highway and Road Area = (23 + 3.2) x 2.0 = 52.4 ha.
Equivalent Residential Land Area = 7.6 x 1.0 = 7.6 ha.
Equivalent Open Area = 15.6 x 0.4 = 6.2 ha.