2022 White Creek Dredging Project

The Department of Natural Resources and Environmental Control (DNREC) is in the engineering phase of a project to dredge White Creek, an important navigation channel in the Inland Bays.

White Creek is northwest of Bethany Beach and flows south to north into Indian River Bay. It serves numerous marinas and boat ramps and connects Assawoman Canal to the bay.

DNREC has taken over responsibility for channel marking from the U.S. Coast Guard for a portion of the White Creek channel, and has placed green markers, as well as a Notice to Mariners, providing further instructions for boaters.

Since dredging last occurred in the early 2000s, shoaling has increasingly impacted navigation in the waterway.

Project Overview

White Creek was determined to be a top priority for dredging as part of DNREC’s data-based method to prioritize dredging projects. This process included stakeholder engagement surveys and analysis of channel depth, boater safety, and environmental considerations.

The goal of the dredging project is to improve navigation for commercial and recreational boaters that use the channel to navigate in the Inland Bays. The dredged material will be used to restore a local marsh such as those found at Holt’s Landing State Park, James Farm Ecological Preserve, Slough’s Gut in Delaware Seashore State Park, the Indian River Inlet Marsh Complex, or the Muddy Neck Complex in the Assawoman Wildlife Area.

DNREC engaged engineering services from Anchor QEA + Woods Hole Group Joint Venture to design the dredge project and oversee its construction.

Analysis of Alternatives

A map showing the project area and options for dredge material placement

The analysis of alternatives conducted by Anchor QEA + Woods Hole Group Joint Venture considered:

  • Channel depths
  • Characteristics of sediments from the channel and potential restoration sites
  • Local marsh topography

The goal was to determine potential costs and logistical issues for dredging and sediment placement options.

Key Conclusions

Approximately 40- to 65-thousand cubic yards of material will need to be dredged to restore previously maintained depths.

The site used to place dredge material from earlier dredge projects is no longer available. Creating a new upland placement site is cost-prohibitive.

The recommended option is to use the material for marsh restoration at some combination of three potential sites:

  • James Farm Ecological Preserve and Slough’s Gut
  • Muddy Neck Marsh Complex in Assawoman Wildlife Area
  • Indian River Inlet Marsh Complex

Selected Project Concept

The design selected by DNREC incorporates restoration of Muddy Neck Marsh Complex using material dredged from White Creek. It was chosen because the marshes at Muddy Neck have the greatest need for restoration.

This option gives DNREC the possibility to also dredge part of Assawoman Canal as part of a multi-phase, multi-year marsh restoration and channel dredging project. Assawoman Canal is another highly ranked waterway in DNREC’s dredging prioritization process. It connects Little Assawoman Bay to Indian River Bay via White Creek.

Selected Project Concept Highlights

Dredge White Creek Main Channel and prongs to a depth of approximately four feet below mean lower low water.

Dredge Assawoman Canal, between the confluence with White Creek and the Central Avenue bridge, to a depth of approximately three feet below mean lower low water.

Restore degraded marsh in Assawoman Wildlife Area at Muddy Neck using thin layer placement techniques.

Public Information Sessions

On July 28, 2021, DNREC hosted a virtual public information session, attended by approximately 125 people, to share information and solicit questions and feedback about the project.

The public information session included a presentation on the project and has led to development of a set of questions and answers about the project.

A second public project information session was held on Jan. 19, 2022.

Beneficial Use of Dredged Material

The material to be dredged consists primarily of mud (silt and clay) and some sand. This material is not suitable to place on local beaches, as was done as part of the 2020 Masseys Ditch Dredging Project.

Instead, this material is ideal for restoring degraded local marshes. The project will benefit the marsh over the long-term by providing additional sediment and elevation, imitating natural processes by applying sediment in a thin layer with the goal of helping the marsh to withstand future sea-level rise.

Restoring degraded marshes using dredged material is a common practice nationwide and has been done in Delaware.

In 2013, DNREC’s Shoreline and Waterway Management Section and Wetlands Monitoring and Assessment Program joined to implement a successful marsh restoration at the Piney Point Tract of Assawoman Wildlife Area. That project used a thin layer of material dredged from Pepper Creek.

Regionally, numerous projects in southern New Jersey have used dredged material to restore marshes.

Anticipated Timeline

A typical dredge project requires the following steps:

  • Pre-Planning/Prioritization
  • Planning, Engineering, Design
  • Permit Acquisition
  • Procurement/Bid
  • Construction
  • Monitoring

Based on the timelines and complexity of these necessary steps, DNREC is targeting a period from fall of 2022 to spring of 2023 to execute the White Creek dredging.

For more information, please contact Jesse Hayden at 302-739-9921.