Stormwater Management Concept 

WHY IS A STORMWATER MANAGEMENT (SM) CONCEPT REVIEW NECESSARY?

The purpose of the Stormwater Management Concept Review is to identify the manner in which stormwater runoff from development will be controlled at the preliminary design stage to prevent damage to streams and other waterways.

WHEN DO I NEED A SM CONCEPT APPROVAL?

A Stormwater Management Concept approval is required for any development activity prior to the application for a Sediment Control Permit or prior to preliminary subdivision plan approval by the M-NCPPC, if applicable.

ARE ANY DEVELOPMENT ACTIVITIES EXEMPT FROM CONCEPT APPROVAL?

• The following development activities are exempt from the SM Concept requirement.
• Agricultural activities.
• Additions or modifications to existing residential structures with less than 5,000 sq. ft. of land disturbance.
• Land-development activities regulated under state laws.

WHAT TYPES OF STORMWATER MANAGEMENT CONCEPTS ARE THERE?

There are two types of stormwater management concepts: on-site control and stormwater management waiver.

• On-site control
• Channel Protection: Management of the increase in discharge from a one year, 24 hour storm event
• Quality Management: Management of runoff through various types of on-site water quality control
• Recharge: Maintenance of existing groundwater recharge rates
• Where historical flooding exists, the Department may also require control of runoff from ten and 100 year storm events

• Waiver: Must meet criteria established in the Montgomery County Code, Section19.24.C

The applicant can request a full or partial waiver of providing on-site stormwater management for channel protection and/or quality control. When granted by the Department of Permitting Services an appropriate stormwater management contribution will be required in accordance with Executive Regulation 4-90AM.

WHAT IS THE STORMWATER MANAGEMENT APPLICATION PROCESS?

Submit a completed SM Concept Application, a copy of the grading or site plan (along with applicable supporting information), and the appropriate application fee. Please refer to the second page of the SM Concept Application for submittal requirements.

CONDITIONS OF APPROVAL

A SM Concept is approved when an approval letter has been issued by the Department of Permitting Services.

OTHER AGENCIES INVOLVED

All reviews of Stormwater Management Concept requests will be coordinated by the divisional staff with the Environmental Planning Division of MNCPPC.

WHAT WILL THE SM CONCEPT APPLICATION COST?

1. For concepts of onsite stormwater management for a single-family residential lot - $1,144.00
2. All other stormwater management concept plans which are 25 acres or less - $2,684.00
3. All other stormwater manaement concept plans which are greater than 25 acres $3,432.00
4. Fees for revisions to previously approved stormwater management concept plans are 50% of the current fee .

The above fees include a 10% automation enhancement fee. Filing fees and permit fees are based on fees in effect on the date the application was filed. All other fees are based on fees in effect at the time the service is requested (revision fee, extension fee, etc.).

WHEN WILL I RECEIVE MY SM CONCEPT APPROVAL?

• A Stormwater Management Concept typically takes approximately three to six weeks for approval.

The approval is valid for the life of the associated preliminary plan approved by MNCPPC or the term of the applicable law and Executive Regulation at the time of approval. Actual processing time may vary according to workload and/or complexity of the project.