Project Purpose and Location

Natural and nature-based features and green infrastructure, working in concert with other flood hazard mitigation measures, are integral elements to control wetland-shoreline erosion, improve floodplain connectivity, and enhance habitat for the City’s flood resilience strategy. 

Wetland restoration, living shorelines, and floodplain restoration along the Eastern Branch of the Elizabeth River were identified as key resilience building strategies as part of an extensive evaluation of structural and non-structural alternatives.

The proposed project will focus on four City-owned properties along the Eastern Branch: Arrowhead Elementary School, Woods of Avalon Park, Carolanne Farms Neighborhood Park, and Ferry Point Park. Opportunities on adjacent privately owned lands are also being explored.

Key Project Facts

  • The first project advancing to design in implementation of the Sea Level Wise Elizabeth River “Adaptation Vision.”
  • Project design and construction is fully funded under the Stormwater Green Infrastructure Master Project of the City’s Flood Protection Program. Additional support includes a $3 million Virginia Department of Conservation & Recreation Community Flood Preparedness Fund grant.
  • Overall schedule for design and permitting is around two years, taking place between early 2022 and early 2024.
  • Construction activities are anticipated to take approximately one year, beginning with contractor procurement in early 2024 and construction completion in early 2025.

Project Need

Coastal and Stormwater Flooding

The Eastern Branch of the Elizabeth River is the key flood entry point into the Elizabeth River watershed. Tidal creeks extending from the main stem of the river connect neighboring properties to the water. During storm events, the elevation of the river can increase by several feet. 

Flooding of low-lying lands can be much worse when high tide, strong coastal wind-driven storm surges, and heavy or extreme rainfall occur simultaneously.

Erosion and Ecological Decline

Historical analysis has revealed that over the past 50 years, development surrounding the river has led to degradation of the marsh system. The City’s future condition modeling predicts continued erosion of tidal marsh along the Eastern Branch, resulting in conversion of healthy marsh into open water and mud flat.

Design Toolkit

High Marsh Protection

High marsh protection is proposed along the shoreline where there is existing marsh. This protection consists of a coir log installed at the edge of the existing marsh, hardwood logs below the high tide line, and marsh plantings in the area between the coir log and hardwood logs. 

The coir log will eventually disintegrate, and the native wetland vegetation will take its place, acting as a shoreline buffer. These mitigation tools will work to stabilize and restore the riverbank. Vegetation will grow up and around the coir logs, eventually creating living shorelines.

Upland Protection

Upland Protection is proposed for areas where the shoreline consists of vegetation or banks that are not marshland. 

This shoreline protection will be installed with hardwood logs set below the high tide line, a coir log along the top of the bank and a vegetated armor mat as stabilization for the area between the coir log and hardwood logs. 

The coir log will eventually disintegrate, and vegetation will grow creating living shorelines.

Ditch Stabilization

It is necessary to stabilize the channels/ditches that drain water from the developed areas surrounding the river to support the installation of living shorelines along the river. Stabilizing these ditches will help provide additional storage capacity and provide erosion protection of the restored shorelines. The existing stormwater ditches along Normandy Avenue will be pools.

The proposed design features will work together to reduce erosion of the tidal marsh, improve water quality, and reconnect floodplain wetlands for improved riparian habitat and flood mitigation.

Current Updates

Design

90% Design has been completed.

Public Information Meeting

A public information meeting was held at the Arrowhead Elementary on May 11, 2023, from 6-7:30 p.m. The meeting included a brief presentation of the project followed by an open format. City staff and design engineers was present to answer questions. 

Large-printed visualizations including artistic renderings of the project area were on display showing the existing and proposed conditions and proposed shoreline protections and ditch stabilization details. For more information, please see the project information meeting summary & presentation.

This project received funding from the Virginia Community Flood Preparedness Fund Grant Program through the Virginia Department of Conservation and Recreation (DCR), via CFPF-21-01-08.