Revised sediment and stormwater regulations for Delaware

Delaware has revised the sediment and stormwater regulations from the Department of Natural Resources and Environmental Control (DNREC).  These changes went into effect on Feb. 11, 2019. 

DNREC logo

 The revised sediment and stormwater regulations will address runoff from the most frequent rainfall event; stormwater volume control; stormwater management for redevelopment; and plan approvals for construction of residential, utility and poultry house projects. 

 In addition to addressing legislative actions, the revised regulations include simplified criteria for the approval of smaller, less impactful projects.  The revised regulations include standards and specifications for each of 17 post-construction stormwater management best management practices (BMPs), and expand the section in the regulations on stormwater offsets to include details regarding fees-in-lieu, banking and stormwater management offset districts.

The revised stormwater and sediment regulations can be found at:

 If you have questions about stormwater and sediment issues in Delaware, please contact:

Barry G. Stingel, ASLA, RLA
Senior Project Consultant
302.316.3277 Ext. 3

Jennifer W. DiJoseph, P.E.
Project Consultant
302.316.3277 Ext. 2

Delaware Sediment & Stormwater Regulations Invalidated by Court

On October 7, 2015 the Delaware Superior Court ruled that the 2014 Sediment & Stormwater Regulations were invalid.  Why?   The very definition of "regulation" came to light.  The Technical Document issued by DNREC to provide guidance for following the new regulations was being enforced by DNREC as if it were law.  If it was intended to be enforced in this way, the Technical Document should have followed Delaware’s Administrative Procedures Act (APA) procedures for adoption as the regulations had.

Delaware Sediment and Stormwater Regulations Invalidated by Court

DNREC has appealed the Court's decision.  In the interim, DNREC has adopted emergency sediment and stormwater regulations, reinstating the 2014 regulations invalidated by the Court and is adopting the Technical Document as part of the regulations.  The interim regulations were adopted under the state's APA and will be in effect for 120 days and may be extended for an additional 60 days while the regulations and Technical Document go through the formal adoption process as required by state law.  

More information on this decision:

If you would like to discuss this issue in depth or would like to discuss your site issues, please contact:

Barry G. Stingel, RLA, ASLA
Senior Landscape Architect & Land Planner


New Water Protection Rule

The USEPA has issued its long awaited new rules under the Clean Water Act.  An extension public comment period preceded these new rules that look to further protect the quality of the nation’s waters.  As with most federal regulations, various parties differ on the appropriateness of the new rules.  Some calling it a shameful power grab by the federal government while others hailing it as much needed regulations to protect an invaluable national resource.  These rules will have significant impacts on future land development. Click here for more information.

new protection water rule

If you have questions about this rule or would like to discuss how this may affect your project(s), please contact:

Chris Reitman, P.E.
Senior Environmental Engineer

Dan Wright, P.E.
Senior Civil Engineer