Allegheny County, PA Environmental Rules: Stormwater Management (2026)
Key Facts
- Section
- § 780-515.A
- Fallback standard
- Ordinance Appendix 5
- Applies to
- Subdivisions/land developments
- Reviewed/approved by
- County Dept. of Economic Development
Summary
Every Allegheny County subdivision or land development affecting stormwater runoff must include a management plan, following municipal rules where they exist or the county's Appendix 5 standards where they don't.
Every subdivision or land development which will affect stormwater runoff characteristics shall include provision for the management of runoff to comply with the following:
(1) Development in areas where municipal stormwater management regulations have been enacted. Proposed subdivisions and land developments located in municipalities or areas of municipalities where municipal stormwater management regulations have been enacted shall comply with the municipal regulations. Stormwater management plans for proposed development in those areas and municipalities shall be approved in accordance with the municipal regulations and reviewed by the County, where County review is required by the municipal ordinance.
(2) Development in areas where municipal stormwater management regulations are not in effect. Proposed subdivisions and land developments located in areas where municipal regulations are not in effect shall comply with the provisions for stormwater management contained in Appendix 5.[1] Appendix 5 is hereby incorporated as a part of this chapter. [1] Editor's Note: Appendix 5 is included at the end of this chapter.
(3) Stormwater management plans for proposed development in areas subject to the provisions of Appendix 5 shall be reviewed by the municipality and approved by the Department.
B. Implementation and enforcement of stormwater management plans.
(1)
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: rev 4857026; v12 updated 2024-06-04; through 06-04-2024).
Full Breakdown
Section 780-515.A of the county Subdivision and Land Development Ordinance requires runoff management provisions for any covered development affecting stormwater characteristics. Where a municipality has its own stormwater regulations, those govern; where none are in effect, the development must follow Appendix 5, which the ordinance incorporates by reference, with plans approved by the County Department of Economic Development.
Violations & Fines
A subdivision or land development plan lacking a compliant stormwater management provision will not receive Department approval; enforcement of Appendix 5 violations follows the ordinance's Article I remedies.
Frequently Asked Questions
Does Allegheny County have its own stormwater rules?
What if my municipality already regulates stormwater?
Sources & Official References
Other rules in Allegheny County
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