Brief Overview
This page is intended to provide a brief introduction to the most significant sections of Chapters 500 (as revised effective December 27, 2006). It is not a legal reference. If you are designing a project, or would like to review all sections, please see the actual text of Chapter 500 and 502.
The numbers (ex. "Sec. 3") below refer to sections of the rule. Links out go to the full text of the sections.
Definitions (Sec. 3). Terms are defined such as "disturbed area", "developed area", "erosion control mix", "impervious area", "infiltration", "landscaped area", "practicable", "pre-development area", "protected natural resource", and "watershed".
Stormwater standards (Sec. 4). This section describes:
- Basic standards (erosion & sedimentation control, inspection & maintenance, and housekeeping)
- General standards
- Phosphorus standard
- Urban impaired stream standard
- Flooding standard
- Easements and covenants
Other applicable standards (Sec. 5). This section describes requirements that may or may not, depending upon the project, apply in addition to the basic, general, urban impaired stream, and flooding standards.
- Management of stormwater discharges
- Discharges to freshwater or coastal wetlands
- Threatened or endangered species
- Additional controls
- Authorization for discharges to public storm sewer systems
Compensation fees and mitigation credit (Sec. 6). This section applies to a project that needs to provide mitigation because it is required to meet the "urban impaired stream standard" or to a project where the DEP has allowed the applicant to reduce acreage treated or lower the phosphorus export reduction to meet the "general standards".
Stormwater permit by rule (PBR) (Sec. 7). This section address subjects such as:
- When a project qualifies (and doesn't)
- Submission requirements
- DEP discretionary authority
Submissions and pre-application meetings (Sec. 8)
Municipal stormwater management programs (Sec. 9). The DEP may allow a municipality or quasi-municipal organization, such as a watershed management district, to substitute a management system for stormwater for the stormwater permit requirement under the Stormwater Management Law (38 MRSA 420-D).
Experimental measure (Sec. 15). This section allows the DEP to approve an experimental best management practice on a case-by-case basis. However, in this case, the department may require the applicant to collect sufficient information on the performance of the experimental BMP to allow evaluation. If the experimental BMP does not perform at least as well as would have been expected from otherwise available BMPs, the department may require the permittee to replace or otherwise redesign the system.
