As-built surveys are required for:
Impervious area (This survey will state the current square footage of impervious area on a specific site(s). The impervious area will be compared with the allowable amount allocated for the site(s) per the approved land development plan and associated regulation.)
Storm drainage BMPs
These as-built surveys with calculations (if applicable) must be submitted into Land Development’s Electronic Plan Management by a professional land surveyor and/or a professional engineer. The submitted plans and calculations must be sealed, signed and dated.
As-built survey general requirements and checklist can be found both in Section 10.0 and Appendix 10-1 of the Post-Construction Ordinance.
Common Reasons for Disapproval of As-Built Surveys
No Professional Land Surveyor seal on plan(s)
Pipe is less than 0.5% slope
The velocity at a discharge point is greater than five fps
Pipe slope differs greatly from design
There is less than two feet of coverage over a pipe and class 4 RCP pipe was not specified
The volume of the BMP is undersized
The BMP aquatic shelf is not within 1 to 1.5 feet below the permanent pool elevation
There is no access point or safety bench for equipment to get to the BMP when it needs maintenance
Outlet devices are not sized according to plans