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Tales of the Coast
Coastal Histories

Dynamic Sustainability: Maryland's Atlantic Coast

Ocean City and Assateague Island

Dynamic Sustainability: Shoreline Management on Maryland's Atlantic Coast

1981-2007, New Principles Enacted with a Systems Approach

Ocean City

By the early 1980s, the Corps had developed a plan for a beach nourishment project at Ocean City. The goal was to provide protection from a "100-year" storm. This project was named the Atlantic Coast of Maryland (Ocean City) Shoreline Protection Project.

The state of Maryland agreed to carry out the first phase of the beach fill to create a recreational beach. In the summer of 1988, therefore, the state dredged offshore shoals and pumped the sand onto the shoreline at Ocean City where bulldozers spread it across the beach.

The Corps began the Federal portion of the project in the summer of 1990. The work consisted of building a steel bulkhead along the boardwalk at the southern end of town; widening the beach in front of the bulkhead; and adding a widened beach and dune line up to the Delaware state line. The Corps used the same offshore sand sources as the State, and the work was completed by the summer of 1991.

A series of very severe storms struck Ocean City between 1991 and 1992. One took place over Halloween in 1991, and the other happened in January of 1992. While the visible beach was significantly eroded after these storms, most of the fill material stayed in the nearshore waters. The post-storm surveys also confirmed that areas near shoreface-attached shoals exhibited more severe erosion than other areas. These locations are called "erosion hot spots."

An emergency fill was done in the summer of 1992. This had not been originally planned but it was deemed necessary to bring the beach back up to the level of protection specified in the plan. The beach nourishment project fulfilled its mission to protect the town from storms because there was virtually no damage to the landward developments during these events.

Intense storms continued through the early and mid 1990s, and another emergency fill was carried out in 1994. The project was accepted as complete in 1994, and renourishment has taken place every four years since 1994. Currently, renourishments are focused on the erosion hot spots near the shoreface-attached shoals.

Starting in 2004, Ocean City was also included in the Long-Term Sand Management Project (LTSM), which is primarily concerned with Assateague Island but also supplements the nourishment at Ocean City.

The Corps began a rehabilitation project on the south jetty in 1984 to repair damages incurred since the 1960s. This project filled holes in the jetty and added a new section to it.

These actions were designed to prevent sediment from entering the inlet, thereby reducing channel shoaling, but they also had the potential to aggravate erosion along northern Assateague. In response, the Corps built three breakwaters along the northern coast of the island to dissipate wave energy in the inlet and prevent erosion from becoming even worse.

By 1990 the ebb-tidal shoal was over a mile wide, and it merged with the northern end of Assateague around this time. The shoal stopped acting as a sand sink and became a sand source. Sediment was transferred across the shoal to the island's shore, and the shoals' sand bars were pushed by waves against the shore. Shoreline retreat rates slowed to about 20 feet per year.

The south jetty was again strengthened in 2002 to keep sediment out of the channel and to ensure that the structure wasn't damaged. Since the implementation of the Long-Term Sand Management project in 2004, the channel has been dredged twice yearly, which keeps it clear for boats and provides sediment for the beach nourishment projects in the region.

A new management plan for Assateague Island National Seashore was drafted in the early 1980s that advocated a middle road between development and wilderness preservation. The plan decreed that recreational facilities could be protected with artificially maintained dunes, but in general overwash and the natural westward migration of the island would not be prevented.

After the storm in January of 1992, officials and residents became concerned that the island would be breached, which could expose mainland communities to storm damage. Studies began in the 1990s to tackle a number of water resource issues including erosion, channel shoaling, and environmental degradation in the bays. The Corps, NPS, the State, and other stakeholders saw these problems as interconnected and thus wanted to develop solutions that dealt with these problems on a regional scale.

In 2002, a one-time, large-scale beach fill was placed onto the beach at the northern end of the island. The second phase of the project became the Long-Term Sand Management (LTSM) Project. It entailed biannual sand bypassing in the nearshore waters along the northern end. Essentially this would replicate the natural process of sediment transport that was being interrupted by the Ocean City Inlet jetties.

The biannual dredge-and-placement operations have continued since 2004, and both the Corps and NPS have been monitoring the beach's response. Analysis of the data is ongoing and an updated sediment budget is expected by the end of the decade.

Two environmental restoration projects have been carried out. Wetland restoration at Isle of Wight has added sediment and salt marsh grasses to this small island along with shoreline protection structures and a recreational pier. Ocean Pines is a mainland location where low and high salt marshes were restored successfully.

In summary, these beach nourishment projects and their development through the late 20th and early 21st centuries demonstrate how the Corps principles have evolved. Dredging and navigation have remained key components of the Corps mission, but storm protection, environmental restoration, and an emphasis on regional solutions also developed during this time.

 

Sand Management

Extensive sampling of potential sand sources and the native beach was conducted before the project began. Monitoring continued before and after the beach fill to evaluate the process of beach nourishment. The Ocean City beach nourishment project was one of the first large-scale applications of beach nourishment.

Adding sand to the littoral system has been much less detrimental than building structures that, like the Ocean City Inlet jetties, can damage areas in the wider region. The emphasis on solutions that consider a range of impacts on the coastal area is a cornerstone of regional sediment management.

Erosion

By the 1990s, after the repairs to the jetties, the adding of the breakwaters, and the ebb-tidal shoal reaching equilibrium, it was still evident that erosion of the northern end was a significant and multifaceted problem.

Sand Sources

Three sand sources were identified for the LTSM project so that no one source would be significantly damaged. One of those sources was the channel itself, so by combining maintenance dredging and beach nourishment, this project would keep the navigation channel clear and counteract erosion at the same time, thereby saving costs.

Regional Sediment Management

A comprehensive understanding of coastal systems and their interconnectedness inspired the Corps to continually investigate new approaches to coastal management. Environmental preservation, long-term sustainability, and increased efficiency became central to the shoreline management projects on Maryland's Atlantic coast. These exemplify the principles of regional sediment management.