Assessment of dual-purpose fish/oyster reefs in the Lynnhaven River, VA

Funding Agency:
Department of Defense

The Lynnhaven River, Virginia, is the southernmost tributary of the Chesapeake Bay. Its watershed lies mostly within the bounds of the heavily urbanized City of Virginia Beach. The river once held an extensive network of intertidal and subtidal oyster reefs, but today the only subtidal reefs are those constructed as part of a river-wide restoration effort. Recently, as part of the Lynnhaven River Basin Ecosystem Restoration Project (LRBER), a joint USACE/City of Virginia Beach led effort, a large network of reef balls and a series of high-relief granite/crushed concrete reefs have been constructed in the Lynnhaven River system. The intent of these reefs are dual-purpose oyster and fish reefs. Many fish species in Chesapeake Bay prefer, and some require, hard reef habitat in order to thrive. This habitat type is rare in the modern-day Bay and was extirpated from the Lynnhaven River decades ago. These dual-purpose oyster/fish reefs are the first of their kind, constructed as part of a large-scale ecosystem restoration project in Chesapeake Bay.

Our objectives are to monitor and document the status of these reefs. For the oyster component, a physical assessment of the reefs is desired. Assessing the reefs for oyster and other attached fauna for density and biomass (dry weight) and for oysters, size-frequency distribution. Approximately 50 samples will be needed to minimize the SE (standard error of the mean) and ensure survey accuracy. 

An assessment of fish use of the reefs is also desired. For this component, a variety of methods could be used. Control sites for this work will also be necessary in order to determine what differences in fish species distribution and abundance, if any, exists between the fish/oyster reef sites and surrounding open sandy bottom areas. 

There are two sites that will need to be monitored. The first site is 8-acres mostly in the low intertidal and shallow water zone. It consists of several thousand reef balls weighing approximately 50 lbs. Each. The second site which is currently under construction is proposed to consist of crushed concrete or granite riprap with an oyster shell veneer. This subtidal, high-relief reef is approximately 18” off the surrounding bottom. The second site will cover anywhere from 23-30 acres post-construction and is approximately -6 ft MLW. 

Statement of Interest/Qualifications Due Date: 22 July 2022

Agency Website

Eligibility Requirements

This opportunity is restricted to non-federal partners of the Chesapeake Bay Cooperative Ecosystems Studies Unit and Piedmont South Atlantic Coast (CESU).

Amount Description

Estimated Total Program Funding (optional): $225,000 dollars total over 3 years. (ex. Base and all options)

Funding Type





Environmental & Life Sciences

External Deadline

July 22, 2022