New Stormwater Design Manual

The Stormwater Program has just updated the Stormwater Design Manual to be compatible with the new Minimum Design Criteria (MDC) that are codified in the new stormwater rules, which went into effect on Jan. 1. Most of the draft manual is available now and all sections will be complete by Jan. 31. The Stormwater Program is accepting comments on the new manual until March 31 and will finalize the manual after that date.

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Comment on the Design Manual and Related Forms


Supplement EZ form (3/1/2017)

O&M EZ form:  This form allows you to create one operation and maintenance agreement for the entire project. 

Training and SCM Crediting

Welcome to the MDC Workshops: NCSU and DEQ are cooperating to offer 1.5-day workshops on the MDC if you would like an intensive training on the new rules and manual. 

Stormwater Reviewer Certification: The expiration dates for all certifications have been extended until September 1, 2017.  People seeking Stormwater Reviewer Certification for the first time should attend a Welcome to the MDC Workshop. 

Draft Stormwater Control Measure Credit Document:  This document lists all SCM credits together facilitate comparisons between different SCMs for the regulated community. It is a joint effort between DEQ’s Stormwater  and Nonpoint Source Planning programs. The document is currently in draft form, but will soon be finalized. 

Stormwater Design Manual Table of Contents

Part A: Common Site and SCM Elements

A-1.     Runoff Treatment – available 3/31/17

A-2.     Runoff Volume Match – available 3/31/17

A-3.     Soils and Vegetation 

A-4.     Common Structures and Materials 

A-5.     Construction 

A-6.    Operation and Maintenance 

A-7.    Guidance on SCM Selection 

Part B: Calculations Guidance 

Part C: Minimum Design Criteria and Recommendations for Stormwater Control Measures

C-0.     MDC for all SCMs

C-1.     Infiltration System

C-2.     Bioretention Cell

C-3.     Wet Pond

C-4.     Stormwater Wetland

C-5.     Permeable Pavement

C-6.     Sand Filter

C-7.     Rainwater Harvesting

C-8.     Green Roof

C-9.     Level Spreader-Filter Strip

C-10.   Disconnected Impervious Surface

C-11.   Treatment Swale

C-12.   Dry Pond

Part D: Minimum Design Criteria and Recommendations for New Stormwater Technologies

D-1.     StormFilter

Part E: Guidance for Specific Types of Sites

E-1.     Low Density

E-2.     Single Family Homes with BUA Limits – available 3/31/17

E-3.     Retrofits

E-4.     Airports

E-5.     Linear Transportation and Greenways

E-6.     Solar Farms

Part F:  Guidance for New Stormwater Technologies


MDC Team: Documents all of the discussions from the stakeholders group that developed the new Minimum Design Criteria