Hart-Miller Island State Park...Creating a Unique Resource Out of Dredged Material

by Arnold "Butch" Norden

W
hich Maryland state park has the best beach in the upper Chesapeake Bay, attracts the largest concentration of shorebirds in Maryland, is accessible only by boat, and is about to double in size? The answer is Hart-Miller Island State Park (HMI), located in the upper Bay, about three-quarters of a mile from the mouth of Back River in Baltimore County. It's a little known gem among the 48 outstanding state parks in our public lands system.

an aerial view of HMIHart-Miller Island State Park was acquired by the State of Maryland in 1977-78 for a very specific purpose. At that time it consisted of three separate islands (Hart, Miller and Pleasure Islands) that together comprised about 250 acres of land. Pleasure Island, the closest to the mainland, was privately developed in the late 1940s as New Bay Shore, an amusement park accessible from the mainland via a wooden bridge. However over the years, New Bay Shore was badly damaged by several storms and finally closed when the bridge washed out in the mid-1960s.

Creating a Park Out of Thin...Water
The original 250 acres were but a fraction of the planned size of the state park. That's not uncommon and parks frequently grow as new parcels are added. However, in the case of HMI, the additional land didn't even exist! The plan called for Hart and Miller Islands to be incorporated into a diked, dredge-material containment facility about two miles long and one mile wide. To achieve this, dredged material would be pumped into an impounded area that, when filled, would be restored and made part of the park.

To make HMI a reality would take 20 years and a myriad of partners. The design, development and management of this ambitious project has been a cooperative effort between the Department of Natural Resources (DNR), the Maryland Port Administration, the U.S. Army Corps of Engineers, Maryland Environmental Service, and the Maryland Department of the Environment.

The initial dike was 18 feet in height and a cross dike divided it into two sections -- a south cell comprising 300 acres and a north cell of 800 acres. Eventually the dike around the south cell was raised to 28 feet and the north cell was raised to 44 feet in height.

The perimeter dike was completed by 1983 and the pumping of dredged material into the south cell was initiated in May of 1984. In 1990 the south cell was considered filled and restoration began, while pumping continued into the north cell. Current plans call for the 800-acre north cell to be added to the state park after it is filled in about five years.

While the south cell was being filled, approximately 100 acres of the original islands were developed and operated by DNR as HMI State Park. The area includes tidal wetlands, sandy coastal forest and open beach. Stone breakwaters protect the beach itself. Currently there are hiking trails, a visitor's center, campsites, composting toilets, picnic facilities, an observation tower and the bathing beach. The park is managed out of North Point State Park in Baltimore County.

A Park Without Parking Lots
Hart-Miller Island is remarkably popular, even though it can only be accessed by boat. Visitorship is not generally recorded but data collected in 1993 documented 43,000 boats in the vicinity of HMI, and on a pleasant summer day hundreds of boats can be counted clustered around the island at any given time. Several years ago local entrepreneurs initiated a ferry service to allow the non-boating public to access the island, but that effort was short-lived.

Planning for restoration of the south cell began as soon as the original perimeter dike was completed and dredged material began to be pumped into the facility in May of 1984. In 1997, a restoration team was established, composed of representatives of all the previously mentioned state and federal agencies, and complimented by a group of very interested and active area residents and members of the Maryland Ornithological Society. The main question posed by all parties was in what capacity the restored island should function. Early suggestions ranged from simple revegetation to a theme park complete with water slides and a wave pool. Level heads prevailed and team discussions centered on appropriate natural habitat that would support species deemed to be of "scarcity and significance."
 


a photo of munitions found during dredging

W
hen the approach channels to Baltimore Harbor were widened and deepened in 2003, an enormous amount of material was dredged up from the bottom of the Patapsco River. Work at similar sites the year before had turned up military ordnance dating from the Battle of Baltimore in 1812. With that in mind the U.S. Army Corps of Engineers had the recovered objects taken by barge to HMI, where a special safety area was set aside for their examination by historians and military explosives experts. Among eight barges of debris, the Corps recovered over 1,300 ordnance items! Most were found to be safe for handling, although several items did contain gunpowder and were detonated within the HMI containment facility.

The ordnance found in 2003 ranged from grapeshot weighing about one ounce, to a 15-inch diameter cannonball that weighed 318 pounds! This historic ordnance is currently being cleaned and prepared at a state lab, and will eventually be turned over to the Maryland Historical Trust for permanent disposition. It is anticipated that some of the items will go on public display at Fort McHenry or the Maryland Port Administration's new visitor center in the Inner Harbor.

Managing for Fussy Flocks
Monitoring of bird populations at HMI, which had begun prior to dike construction, was initiated on a systematic basis in 1983. Robert Ringler and Gene Scarpulla, members of the Maryland Ornithological Society, did a masterful job of identifying and counting bird species at the island on a weekly basis. As bird census data began to accumulate, it soon became clear that HMI was attracting vast numbers of shore- and waterbirds, far more than had ever been seen previously at any locality in the upper Bay.

The open water and exposed mudflats were perfect for migrating shorebirds and waterfowl, providing vital habitat in a part of the region where such habitat was rare. The only problem was that there was no effective way to control water levels to ensure that suitable mudflats were available when shorebirds migrated through the area in spring and fall, and that standing water was present for waterfowl in summer and winter.

After much consideration the restoration team decided to develop HMI as habitat for birds, specifically for migrating shorebirds, nesting terns and grassland nesting songbirds. It was determined that the site would be developed with upland grassland and wetlands grading into an extensive pool with a 1-acre nesting island. The water in the pool would fluctuate to alternately provide open water and mudflat habitat, the timing of which would be managed to provide optimal conditions for migrating shorebirds. Water would be drained to expose fresh mudflats during spring and fall migration periods, and pumped into the pond in winter and summer to provide open water for ducks and other waterfowl.

This seasonal fluctuation has a dual purpose - in addition to providing much needed habitat for resident and migrant birds, it will also serve to control the growth of phragmites, a pervasive invasive reed that is a major problem at dredged material containment sites and other disturbed areas.

The final plan for HMI provides a 4-acre water intake pond, a fluctuating pool pond with a half-acre nesting island, about 130 acres of seasonally exposed mudflats, and approximately 140 acres of upland grassland, shrub and forest habitat. A permanent pool of roughly 28 acres will surround the nesting island, providing a safe area for nesting species, such as the threatened least tern, which requires nesting sites secure from predators such as foxes and raccoons.

 

Come On In, the Water's Fine...
The site has been carefully engineered to make all this work. Bay water will flow A photo showing stone jettys protecting the shoreline of HMI from erosionby tidal action into the water intake pond through a culvert equipped with a one-way valve. Two pumps will send water on demand into the mudflat/pool, either directly into the pool, or trickling from pipes so that it runs down across the mudflats through a mudflat hydration sprinkler system. The water level in the pool pond will be controlled by natural precipitation and supported by pumped water when necessary. Excess water will be released through a sluice gate located near the southeastern corner of the south cell.

The anticipated draw down/flooding cycle will provide a full pool for wintering waterfowl from December to February; draw down to provide mudflats for migrating shorebirds March through May; be flooded to rehydrate mudflats in June; provide a full pool for summer waterfowl in July; drawdown to provide mudflats for winter migrants from August to September; and flood to full pool for wintering waterfowl, October to November.

The water management system is currently being installed and tested, the upland planting is ongoing, and plans are being made for the transfer of the 300-acre south cell to DNR's management sometime this year. The south cell addition will be maintained as a wildlife preserve with nature trails and interpretive signs. While visitors will be required to stay on marked trails, those that make their way to HMI will be able to enjoy a truly remarkable concentration of species, made possible by the creation and management of a completely artificial habitat complex.

To date, 278 species of birds have been sighted at HMI, and more than 50 species have been found to nest there. One of the most recent nesting records is a pair of bald eagles that established a nest this year.

HMI is a wonderful example of how a multi-agency interdisciplinary planning team can take an acknowledged environmental problem, like the placement of dredged material, and create valuable wildlife habitat and an outstanding recreational opportunity.

For more information about Hart-Miller Island State Park, visit the DNR website at www.dnr.maryland.gov/publiclands. For volunteer opportunities, contact Tina Bianca at tbianca@dnr.state.md.us.

Arnold "Butch" Norden
is a natural resources planner with DNR's Resource Planning unit.


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