A. 
The Department of Public Works shall require from the developer a surety or cash bond, irrevocable letter of credit, or performance bond prior to the issuance of any grading permit for the construction of a development requiring a stormwater management facility. The amount of the security shall not be less than the total estimated construction cost of the stormwater management facility, site grading, structures necessary to convey runoff to the stormwater facility and the estimated construction cost of all erosion and sediment control best management practices (including temporary and permanent stabilization). The bond required in this section shall include provisions relative to forfeiture for failure to complete work specified in the approved stormwater management plan, compliance with all of the provisions of this chapter, and other applicable laws and regulations, and any time limitations.
B. 
The bond shall not be fully released without a final inspection of the completed work by the Department of Public Works, submission and approval of "as-built" plans and related documentation (as required by the Department of Public Works' stormwater management as-built checklist), and certification of completion by the Department of Public Works that the stormwater management facilities comply with the approved plan and the provisions of this chapter. Upon completion of the stormwater management facilities, the owner/developer may submit a written request along with the required reports and certifications for a partial release of the stormwater management bond. After review and approval, the Department of Public Works may release a portion of the bond, but in no case will the partial release exceed 20% of the original bond amount. The remaining 8% will be released upon completion of the project and the review and approval of the stormwater management as-built plans.