A financial assurance is required as a condition of issuing a Storm Water Permit. The purpose of the financial assurance is to ensure compliance with the County ordinance, including proper “closure” on the project. The conditions for release include the following items, which are described in more detail in the Financial Assurance Receipt:
- Accepting an “as-built” survey
- Accepting verification of construction
- Completing a satisfactory final inspection
- Receiving a copy of the recorded maintenance agreement
(Note: If final site stabilization cannot occur until the following growing season, the financial assurance will be held until that time.)
Most local communities will collect a substantial financial assurance (letter of credit, etc.) for grading and road construction work, which can also be used to enforce the erosion control and storm water plans. Because of this, the county’s financial assurance is a much smaller amount, focusing primarily on the “closure” issues described above. The minimum amounts are listed in the Fee Schedule.
Note: The LRD may exempt a project from the financial assurance requirements if the County has other regulatory means to ensure compliance, such as withholding an occupancy permit.
To ensure proper installation of storm water management practices in accordance with approved plans and technical standards, the County requires that a professional engineer oversees and certifies construction. A standard (Verification Form) is used for this purpose. As a condition of returning the financial assurance noted above, this form (or equivalent) must be completed and submitted to the County along with a set of “as-built” plans. The “as-built” plans must show actual surveyed locations and elevations of key features of the storm water facility, such as berms, spillways, pipes, basin bottom, safety shelf, and water surface.
The County has adopted minimum standards for "as-built" (construction documentation).
Construction verification is very important for the future maintenance of the storm water practice. For example, the "as-built" elevations will be used as future references for determining when accumulated sediment should be removed from a wet detention basin.
By completing the Verification Form, the engineer is verifying that all items have been installed in accordance with approved plans, applicable state technical standards, and the approved construction inspection schedule. Many items cannot be observed by periodic County site visits/inspections, but are very important to ensure the proper function of the storm water practice. Using a large wet detention basin for an example, by affixing their engineering stamp on the form, the project engineer is certifying that:
- Topsoil was stripped beneath the earthen berm.
- A keyway was constructed beneath the berm (if pool is > 3 feet up embankment).
- Final elevations for pond bottom, backslopes and top of berm meet plan requirements.
- The required soil compaction has been obtained for berm construction (90% Standard Proctor).
- All final berm elevations have allowed for at least 5% soil settling.
- The planned safety shelf elevations and length (8 feet min.) have been obtained, and the required topsoil depth has been applied to the shelf.
- The outlet pipe and emergency spillway elevations are within tolerable accuracies.
- Anti-seep collars or pipe bedding has been installed and proper compaction techniques were utilized for the installation of any outlet structures extending through the berm.
- No unforeseen soil conditions were encountered during construction that would cause excessive infiltration and loss of the planned permanent pool.
- The correct seeding and fertilizing has occurred, as specified.