At SRA our job is to help communities improve their local environment and restore the Severn River. Good communication is really important. So we’ve put together this page to let you know about what’s happening with the stormwater management project at Carrollton Manor. If you ever have any questions or concerns, please our Restoration Manager know: ben@severnriver.org

Click on any picture to make it bigger or to download.

We really want your input and feedback on the project (see Project Summary below). Right now, while the project is still in its early stages, is the best opportunity to make sure to get it right. Please let our Restoration Manager know what you think.  As we get closer to a finished design, there will be less wiggle room to make changes. Once the design is 60% complete, it will be locked in and we won’t be able to make changes.

SRA is a 501c3 non-profit organization with experience and success at pursuing funding and project management for pollution reduction and environmental restoration. Our vision is a thriving Severn River by 2050, and our mission is to connect the people who live, work, and play on the Severn River to restore and protect it for all of our communities.

Project Origin

Carrollton Manor in Severna Park, Maryland, has three community-owned parcels which have experienced erosion from stormwater. The Severn River Association (SRA) and the Carrollton Manor community have decided to collaborate to design and implement a solution.

SRA will work to gain grant funding to pursue this project, with aims to address the primary goal of reducing nutrient and sediment pollution entering the Severn River.

Project Environmental Benefits

• Tax Incentives
• Reduce nitrogen, phosphorus, and sediment pollution entering the Severn River.
• Decrease the turbidity of the water.
• Create a healthier ecosystem for aquatic life to thrive in.
• Increase biodiversity in the Severn River.

What’s the Big Deal About Stormwater, Anyway?

Great question!

As you’re probably already well aware, storms can cause flooding and erosion. Carrollton Manor experiences this with all of the impervious surfaces like roads and side walks. Does something like this look familiar?

When water runs downhill it carries sediments (to which phosphorus ‘sticks’), dissolves nitrogen and carries these nutrients with it, down to the Severn and the Chesapeake Bay. Nutrients sound good, right? We need nutrition after all.

Yes—but to a point.

When there are too many nutrients (either nitrogen or phosphorus), it spurs algae populations to grow out of control. Nitrogen and phosphorus are basically what’s in plant fertilizer, as many gardeners know. The algae population grows so much that it uses up all the nutrients, but then the algae ‘starve’ to death and sink to the bottom of the water. The algae then decompose and the bacteria decomposing the algae use up oxygen, creating dead zones where oxygen levels are too low for most organisms (e.g. rockfish, oysters, and crabs) to survive. Overgrowth of algae and dead zones decrease biodiversity which in turn impacts humans and other organisms that feed and rely on these aquatic organisms.

SRA water quality monitoring in the Severn River records low oxygen levels frequently during summer that indicates the presence of dead zones throughout the river. This is a problem going on in your backyard.

This project will decrease the untreated stormwater runoff that contributes to these dead zones. Additionally, the projects will help curtail the flooding, erosion, and sedimentation in the community.

Project Summary

The overall goal of this project is to treat stormwater running down to Sunset Beach and to prevent erosion at Crab Away while also further enhancing the Hillbottom area with additional native plants. These efforts will protect community assets and improve the water quality of  Severn River by reducing nitrogen, phosphorus and sediment pollution from stormwater runoff. To achieve this goal, the primary objective is to design and implement a nature-based stormwater management solution that captures, slows, and treats runoff through infiltration practices such as a rain garden. By partnering with Carrollton Manor Improvement Association (CMIA), this project will serve as a visible model for other communities to implement similar solutions. Ultimately, the project will increase native habitat and biodiversity while also enhancing community awareness through education and signage.

SRA is currently seeking grant funding for this project. Funding could be awarded in full, in part, or not at all. If unsuccessful, SRA will try again. A ‘no’ is not final or forever.

There are four stages to the project:

1. Identifying community needs and interests
2. Engineering design and permitting
3. Construction
4. Maintenance

Project Design and Construction

SRA wants to make sure that the project is something that the community will enjoy (in addition to all the great environmental benefits). Keep in mind that, as with so many things in life, there are trade-offs to consider. We want to understand what you value so the project will reflect those values. So, right now we want your feedback, especially while the project is still in its early stages. Now is the best opportunity to make sure to get it right. Please let me know what you think. You can email Ben any time, ben@severnriver.org

CMIA will be consulted at each stage of design and will provide written approval at the 30%, 60%, 90% and 100% stages prior to moving forward. Community members will be apprised of progress through emails, community meetings, and this project webpage.

SRA will write grant proposals, manage the grants, guide CMIA through the contractor bid process, manage the grant, oversee contractors, obtain any required permits, secure construction funding and maintain the project for the first five years post construction.

SRA anticipates requesting design funding through Chesapeake Bay Trust’s Anne Arundel County Watershed Restoration Grant.

Maintenance

Once constructed, SRA will be responsible for maintaining the project for the first five years. SRA anticipates contracting with GreenLift (www.greenlift.net), which provides green job training for returning citizens. After five years, responsibility for maintenance will be transferred to CMIA.

Maintenance obligations are specified in the stormwater maintenance Memorandum of Understanding (MOU) with Anne Arundel County include:

• Weeding, mulching (if/as needed), trash removal, and general aesthetic maintenance
• Vegetation: 85% survival, and it can’t be removed or modified without approval
• County can, during business hours and with advanced notice, verify & inspect the project to ensure maintenance, and this level of access runs with the land
• County receives the water quality improvement credits
• County provides structural maintenance (anything really big)
• Post-construction, can’t alter the project without approval

SRA estimates maintenance costs to be about $3,600 annually if contracted out, but many communities opt to hold volunteer days annually (often around Earth Day). SRA can help organize volunteer days if desired.

Timeline

• March, 2026 – meeting with community to identity erosion and stormwater treatment concerns
• April, 2026 – receive board go ahead to pursue grant funding
• June, 2026 – receive bids from potential contractors, CMIA select contractor
• July 2026 to February 2027 – hold community meetings to discuss desired outcomes, develop project proposal
• February 2027 – Submit proposal to Chesapeake Bay Trust
• May 2027 – Hear back from Chesapeake Bay Trust
• June 2027 to February 2028 – Design engineering for project
• February 2028 – apply for construction funding
• June 2028 – hear back about construction funding
• August 2028 – construction complete, begin SRA maintenance
• August 2033 – End SRA maintenance, begin community maintenance

Community Questions & Concerns

​​Let SRA know your thoughts about the project. We will update this section with how these will be addressed.

How much will this cost the community?

• Community contribution towards the project helps to leverage grant dollars and is attractive to grant funders. For many grants it is not required, however it’s heavily encouraged. Because it is not required there is no specific amount of formula for determining the cost. It should be a meaningful contribution based on what the community feels it can do.

What will it look like?

• We will solicit concepts from potential contractors and the community will be able to decide which contractor they prefer. There is give and take, and opportunity for the community to contribute to the design in the beginning stage. There is most flexibility early on, with decreasing flexibility as time goes on and engineering work progresses.

There are three community parcels. Which should we do first? Should we do them all at once?

• We can do all three at once to optimize the result.

Photos

See pictures of the problem areas in this Photo album 

Presentations

Community Stormwater and Erosion June 2025