The plans must be submitted with all existing WSSC water and sewer facilities plotted on the plan and profile views. The plan view should clearly depict the exact location of the following structures.
- Fire Hydrants
- Water and sewer manholes
- Water valve vaults or boxes
- Water meter, curb vaults, or boxes
- Test station
Any grade changes over existing WSSC facility must be plotted on the water/sewer as-built profiles and included with the first plan submission. In fill situations, where grading is increased by more than 2’, submit loading calculations supporting that the pipeline can withstand the increased loads, as per the Pipeline Design Manual – Part 3 – Common Design Guidelines, Section 11 – “Loading Analysis of Existing Pipelines”.
Grading that removes cover over a pipeline maintains minimum permissible cover as per the Pipeline Design Manual – Part 3 – Common Design Guidelines, Section 12 – “Related Design and Analysis”
Manholes, vaults, and water valve boxes are not permitted in curb or gutter pans. Cone sections or a precast manhole can sometimes be rotated to clear curb and gutter.
Storm drain crossings and placement of inlets require a minimum 5’ horizontal, and 1’ vertical clearance, as measured from outside of structure/pipe to outside of structure/pipe, from existing WSSC facilities. Storm drain crossings should be as close to perpendicular as possible to WSSC mains. Skewed alignments are normally not permitted. Minimum vertical clearance is one and one-half feet (1.5’) or 18-inches (18”) if the relocation is subject to MDE water and sewer construction permitting. Refer to Pipeline Design Manual – Part 3 – Common Design Guidelines - Section 3, Pipeline Crossings and Clearances.
The placement of light poles, tree pits for landscaping projects, signs, etc. must maintain the minimum 5’ horizontal clearance requirement.
Pressure reducing/relief valve vaults are not permitted in paved roadways.
Show all utility crossing locations on the storm drain plans and profiles. If the proposed storm drain elements conflict with WSSC assets, adjustments to WSSC assets will be required. If the vertical adjustment impacts less than 20 linear feet of pipe, when it is necessary to lower a water main, the adjustment may be designed on the storm drain profile without requiring additional profile sheets. If the adjustment impacts greater than 20 linear feet of pipe, the Applicant must include a separate profile specific to the relocated water main and include all utility crossings
SWM plans must indicate the locations of the 1-, 2-, 10-, and the 100-year floodplains, as applicable. SWM facilities must show the controlling storm event water surface elevation (WSEL).
Last Modified: July 30, 2026, 8:57 am EDT