New Castle County, DE Environmental Rules: Coastal Development (2026)
Key Facts
- Governing section
- New Castle County Code § 40.02.242(D)
- New HI districts
- None allowed anywhere inside the Coastal Zone
- Existing HI limit
- Only parcels formerly zoned M-3 keep HI status
- Plan disclosure
- Appendix 1, Item 70 requires a Coastal Zone note
- State permit
- DNREC Secretary decision required before operation begins
- County role
- Zoning only; the Coastal Zone Act itself is state law
Summary
New Castle County's Unified Development Code blocks any new Heavy Industry (HI) zoning district from being created inside Delaware's Coastal Zone. Existing HI districts survive only where the parcel was already zoned M-3 under the county's former zoning map, and any use the state's Coastal Zone Act prohibits stays prohibited regardless of the underlying zoning designation.
This district shall be permitted in coastal zones provided that any use prohibited by the Delaware Coastal Zone Act shall remain prohibited, and provided that such districts were zoned M-3 under the former New Castle County zoning maps. No new HI districts shall be created in a coastal zone.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Code of Ordinances: Supplement 5).
Full Breakdown
242 of the county's Unified Development Code defines the Heavy Industry (HI) District for the county's largest industrial developments, the ones tied to rail lines or navigable marine waterways. ' That means the Department of Land Use cannot approve a rezoning application creating a fresh HI district anywhere the Coastal Zone Act reaches, no matter what the applicant proposes to build; only parcels that already carried the legacy M-3 designation before the UDC recodification keep HI status there. The UDC also makes coastal-zone status a mandatory disclosure on development plans.
' A plan submitted without that note where it applies is incomplete under the checklist. The underlying prohibition, the Delaware Coastal Zone Act, is state law administered by DNREC, not a county ordinance, so the county's role stops at zoning and plan review; the manufacturing or heavy-industrial permit decision itself belongs to the Secretary of DNREC.
Violations & Fines
There is no county fine tied to this section; the consequence is that the Department of Land Use will reject a rezoning application seeking a new HI district in the coastal zone outright, and will not certify a site plan missing the required Appendix 1, Item 70 Coastal Zone note. Building or operating a manufacturing or heavy-industrial use in the zone without the DNREC Secretary's decision violates the state Coastal Zone Act itself, a separate state-level offense DNREC enforces, not the county.
Frequently Asked Questions
Can New Castle County create a new Heavy Industry zoning district on the Delaware River waterfront?
Does the county have its own Coastal Zone Act?
What has to appear on a site plan located in the Coastal Zone?
Can an existing Heavy Industry district in the Coastal Zone keep operating?
Sources & Official References
Other rules in New Castle County
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