Delaware Wetlands and Subaqueous Lands Permits: DNREC's Coastal and In-Water Regulation
Delaware's coastal corridor — Delaware Bay, the Atlantic beaches, the Inland Bays, and connected tidal creeks and marshes — is regulated through two state statutes under DNREC: the Delaware Wetlands Act (7 Del. C. Ch. 66) covering tidal wetlands and large non-tidal wetlands, and the Subaqueous Lands Act (7 Del. C. Ch. 72) covering submerged land and tidelands. For developers and contractors working docks, bulkheads, living shorelines, marina expansions, shoreline stabilization, or buildings on lots with tidal wetland fringe, both statutes routinely apply alongside federal USACE Section 404 permits. This essay walks the regulatory stack.
Delaware Wetlands Act — 7 Del. C. Ch. 66
Covers tidal wetlands and non-tidal wetlands encompassing 400+ contiguous acres. Wetlands defined as lands at or below two feet above local mean high water that support specific plant species, per official State Wetland Maps.
Activities requiring permit:
- Dredging.
- Draining.
- Filling.
- Construction of any kind — piers, jetties, breakwaters, boat ramps.
- Bulkheading.
- Mining.
- Drilling.
- Excavation.
Exemptions include: specific mosquito control activities, navigational aids construction, duck blinds, footbridges, wildlife nesting structures, grazing, haying, hunting, fishing, trapping.
Primary source: dnrec.delaware.gov (Wetlands and Waterways Section).
Subaqueous Lands Act — 7 Del. C. Ch. 72
Covers activities on, in, or over "subaqueous lands" — submerged lands and tidelands:
- Lands below mean low tide in all tidal waters.
- Beds of rivers, streams, lakes, bays, inlets.
- Up to ordinary high-water line for non-tidal waters.
Regulated activities — use, alteration, or modification of subaqueous lands:
- Depositing materials.
- Removing or extracting materials.
- Construction, modification, repair, or reconstruction of structures — docks, piers, buoys, ramps, dolphins, pilings, dams, culverts, bridges, bank/channel stabilization (rip-rap, groins, seawalls, breakwaters, bulkheads).
- Laying pipelines, electric transmission lines, or telephone lines in, on, over, or under public subaqueous lands.
- Establishing an anchorage for mooring more than two vessels.
Exemptions include routine maintenance that doesn't change structure purpose, scope, or capacity. Repair or structural replacement above mean low tide that doesn't increase dimensions or change use may not require a permit.
Interaction with federal USACE Section 404
Clean Water Act Section 404 regulates discharge of dredged or fill material into "waters of the United States," including wetlands. USACE issues Section 404 permits.
- Projects requiring USACE Section 404 permit generally also need a project-specific Water Quality Certification from DNREC to ensure the federally-authorized discharge doesn't violate DE Water Quality Standards.
- Most projects impacting wetlands or subaqueous lands in DE require both state DNREC permits and federal USACE permits.
- EPA also has role in Section 404 enforcement and can veto Corps decisions.
Interaction with DelDOT
DelDOT (see our DelDOT essay) must comply with CWA and state regulations. For transportation infrastructure projects affecting wetlands/waters (road widening, bridge replacements, wetland mitigation), DelDOT coordinates with DNREC's Wetlands and Waterways Section for required permits. Private developers with road frontage work affecting ROW-adjacent wetlands similarly coordinate.
Interaction with local permits
Local governments handle planning and zoning (see our DE County Zoning essay). DNREC administers state-level environmental permits. Projects impacting wetlands or subaqueous lands therefore typically require both:
- State DNREC permits (Wetlands, Subaqueous, Water Quality Certification).
- Local zoning and building permits (county or municipal).
DNREC's Regulatory Advisory Service provides assistance for firms needing multiple state permits — a useful starting point for complex coastal projects.
The typical stack for a coastal DE commercial project
- Local zoning approval — county or municipal.
- Beach Preservation Act review if work is on or near beaches (7 Del. C. Ch. 68).
- DNREC Wetlands Act permit for tidal wetland impacts.
- DNREC Subaqueous Lands permit for submerged-land activities (docks, bulkheads, etc.).
- DNREC Water Quality Certification for Section 404-triggering work.
- USACE Section 404 permit from the Philadelphia District.
- USACE Section 10 permit (Rivers and Harbors Act) if work is in navigable waters.
- Stormwater review through Conservation District or approved city (see our DE Conservation District essay), plus RPv calculation (see our DE RPv essay).
- DelDOT entrance permit if fronting a state highway.
- Local building permit.
- Coastal Zone Act only if heavy industry (see our DE Coastal Zone Act essay).
Practical considerations
- State Wetland Maps are authoritative for Ch. 66 coverage. Check your parcel against them.
- Mean high water and mean low tide lines are the operational boundaries for Ch. 66 and Ch. 72. Surveyed delineation matters.
- Joint DNREC-USACE processing possible — DNREC's approval combined with federal permit for efficiency where applicable.
- Mitigation — impacts to wetlands and subaqueous lands typically require mitigation (restoration, creation, enhancement, preservation, or banking).
- Time costs are real. Wetlands and subaqueous permits routinely take 3-9+ months depending on complexity.
- Coastal corridor projects may engage multiple overlays simultaneously.
How DE compares to neighboring states
- Maryland. Tidal Wetlands Act administered by MDE; Non-Tidal Wetlands Protection Act for broader inland wetland protection.
- New Jersey. Freshwater Wetlands Protection Act and Coastal Zone Management Rules under NJDEP.
- Pennsylvania. Chapter 105 Dam Safety and Waterway Management regulates similar activities inland.
- Virginia. Tidal Wetlands Act administered by VMRC and local wetlands boards; separate Chesapeake Bay Preservation Act at locality level (see our VA CBPA essay).
- Delaware. State-level DNREC administration of both tidal wetlands (Ch. 66) and subaqueous lands (Ch. 72), plus Water Quality Certification for Section 404 coordination.
What to do with this
If your project is in or near tidal water: scope wetlands and subaqueous lands at pre-design. State Wetland Map check is step one.
If you're dredging, bulkheading, or building docks/piers: both Ch. 66 and Ch. 72 likely apply, plus USACE Section 404.
If you're a contractor new to DE coastal work: engage DNREC Regulatory Advisory Service for pre-submission scoping.
If you're budgeting: wetlands mitigation is a real line item — not a contingency.
For adjacent DE frameworks, see our DE Coastal Zone Act essay, DE County Zoning essay, and DE Conservation District essay.
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