High Street Green Infrastructure Engineered Designs

Nanticoke Watershed Alliance

High Street Green Infrastructure

Engineered Designs

DUE: August 20, 2025

Request for Proposals

Background Information

The mission, goals, and objectives of the Nanticoke Watershed Alliance (NWA) are developed by consensus with our partnership. The Alliance includes partners from Maryland and Delaware, including representatives from industry, agriculture, environment, business, community, state, local, and federal governmental organizations.

The Nanticoke River is a 64-mile river that begins in southern Delaware and flows southwest into the Eastern Shore of Maryland, emptying into the Chesapeake Bay. One of the Chesapeake’s healthiest rivers, the Nanticoke’s 725,000-acre watershed provides excellent habitat of significance for many nationally threatened plants and animals. The Nanticoke is the most biologically diverse watershed on Delmarva and supports excellent fisheries. It has a rich history, properties on the National Register of Historic Places, and the northernmost stands of bald cypress on the Atlantic Coast. It also has the highest concentration of Bald Eagles in the northeastern United States.

NWA’s Mission: Fostering partnerships and progress in conserving the natural, cultural, and recreational resources of the Nanticoke River Watershed through dialogue, collaborative outreach and education.

NWA’s Core Values:

Conservation– The health of the Nanticoke River watershed is paramount.
Collaboration– We embody partnership through action.
Communication– We value diverse voices and viewpoints where all have a place at the table. We embrace constructive, open dialog as a means to problem solving.
Scientific integrity– We rely on sound science to assess the health of the watershed and share information with the community.
Education– We are committed to sharing with others the importance of conserving the watershed.

The NWA has five full time employees that coordinate a wide variety of projects and programs. Visit www.NanticokeRiver.org to learn more.

Scope of Services

The Nanticoke Watershed Alliance, in partnership with the City of Seaford and Seaford’s Business District, is requesting proposals to develop engineered designs for the High Street Phase 2 Green Infrastructure Project. Phase 2 is the second of three sections of High Street (from Pine Street to Pearl Street). A map and photos of the Phase 2 portion are located at the end of this document.

The project is for engineering designs of stormwater best management practices (BMPs) that include retrofitting curb bump-outs for stormwater management, replacing impervious asphalt with porous pavers or porous concrete in parallel parking spaces, and evaluating the use of stormwater tree trenches and prefabricated technologies to reduce runoff volumes and increase groundwater infiltration on High Street in Seaford, DE.

Upon implementation this project will, reduce stormwater runoff pollution, decrease I&I issues nearby, improve pollinator habitat, decrease the heat island affect and improve property values in an underserved community. The City of Seaford also plans to match the current look and feel of the contiguous main shopping corridor.

The NWA seeks a dynamic firm to work with the City of Seaford, the Nanticoke Watershed Alliance and interested parties within the City to develop engineered designs by Spring of 2026. Services must include:

Participation in meetings with partners to educate stakeholders and the community about nature-based solutions, and to get their input for the development of the designs.
Site map that includes:

Property boundaries
Project boundary
Field-run topographic survey of existing conditions
Drainage area to the practice and impervious cover in the drainage area
Mapped utilities and roads
Proposed design (grade changes, drainage structures, rock placement, etc.)
Landowner signature on the plan, which indicates project endorsement

Copy of soil survey mapping and field confirmation of soil drainage class
Site details (e.g., topographic lines, land uses, and soils)
Planting plan (plant locations and plant types)
Site photos
Calculations of

Total drainage area treated
Impervious acres treated
Estimated cost per acre treated (at a one-inch runoff level)
TN, TP, and TSS reductions for BMP implementation

Cost projections for full implementation, operation and maintenance. Funders consider a truly cost-effective project as one that costs less than $100,000 per impervious drainage acre treated (at a one-inch runoff level), not including costs of gray infrastructure elements.
Maintenance plan needs of all proposed implementation practices in design are to be identified so they can be documented in the final report.
Final design drawings and specifications with proof of permit submission by the end of the grant term.

Evaluation Criteria

A review and selection committee made up of Nanticoke Watershed Alliance and the City of Seaford Staff will evaluate the consultants based on the proposals submitted. If necessary, an oral interview may be conducted with submitting consultants.

Ranking of the Proposals will be based on the following point system (100 points maximum):

Inclusion of all required items and completeness of the Proposal (5 points)
Understanding of the work to be done (25 points)
Previous experience of similar projects completed on time and within budget (20 points)
Qualified and experienced personnel in the project team (15 points)
Capability of developing innovative or advanced techniques (10 points)
Familiarity with county, state and federal procedures (10 points)
Commitment to adhering to the project schedule and budget (5 points)
Clear description of the tasks and demonstrated technical ability (10 points)

Application Instructions

Interested firms are invited to submit a proposal by August 20, 2025. The work described in the proposal is expected to be completed by May 29, 2026.

The proposal should include: