The Virginia Wetlands Report the Virginia Wetlands Report
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Summer 2004 TheThe VirginiaVirginia Vol. 19, No. 2 WetlandsWetlands ReportReport Preserving The Bay’s Living Shorelines A Growing Grass-roots Effort By Tom Barnard he shores of the Chesapeake Bay, particular, the complex interrelated na- tions between the upland riparian envi- T and in particular the myriad of ture of the upland and aquatic systems. ronments (e.g. the forested buffer) and smaller creeks and guts that run inland However, the “armoring” of the shore- the marshes, tidal flats and shallow off its four major rivers, have for thou- line against erosion, with the accompa- water habitat. This, in turn, can lead to sands of years been buffered and pro- nying loss of most of the living aspects the drowning of fringe wetlands as sea tected from the forces of erosion by of the shoreline, continues at an ex- level rises and the marsh can not move communities of salt tolerant landward (up slope) or trap sedi- grasses, sedges and shrubs, collec- ments running off the land, to com- tively called tidal marshes. At the pensate for the rising water levels. same time, these natural communi- The eventual result is that the ties have served important ecologi- marsh is drowned and lost from the cal functions, as nurseries, habitat system. There are alternative ap- and primary food source for valu- proaches available which utilize able bay fauna such as fishes and “softer” more natural shoreline blue crabs. They also serve to filter treatments or incorporate aspects sediments and other pollutants of the living landscape while mini- running off the adjacent uplands. mizing engineered, structural ero- With the development of the sion control. bay watershed over time, land use Many shorefront landowners has changed and forested upland are unaware of these techniques buffers have been replaced by and would prefer a natural shore- farms, housing developments, in- Erosion control using low profile rock riprap line to hardened shorelines such as dustries, marinas and other forms of with planted marsh. stone revetments or bulkheads. economic growth. Growth has Private waterfront property owners changed the bay landscape and led to tremely high rate. In 2002 and 2003, the collectively control the majority of significant loss of living resources over Commonwealth of Virginia permitted Maryland and Virginia’s shoreline and time, including non-tidal wetlands and construction of shoreline erosion con- thus, represent a significant opportu- tidal fringing marshes. Unfortunately, trol structures along 14.4 and 17.7 miles nity to improve the water quality and these anthropogenic losses have oc- of bay shoreline, respectively. These habitat of the Chesapeake and Coastal curred concurrently with sea level rise numbers alone are alarming but VIMS’ Bays. For this reason, a Living Shore- which has served not only to increase data further indicate that over the last lines Stewardship Initiative (LSSI) has natural shoreline erosion rates and ten years, Virginia has permitted the been set in motion. marsh loss but also lead to accelerated “hardening” of an average 18.5 miles of Originally begun in Maryland with attempts by homeowners to protect shoreline per year (VIMS Shoreline funding from The Keith Campbell their upland and thus further exacerbate Permit Data Base). Foundation for the Environment, the shoreline marsh losses. Much of this shoreline loss is un- initiative has grown into a bi-state, Only relatively recently have scien- necessary or structurally over-designed multi-agency collaborative effort in- tists demonstrated many of the ecologi- for the level of erosion involved. Purely volving the states of Maryland and cal functions performed by these structural approaches tend to cut off Virginia. Funding now is also being natural shoreline communities and, in the connections and natural interac- provided by the Maryland Department VWR — 1 of Natural Resources and the Chesa- goal include: using science to drive ! Physical integrity of original design peake Bay Trust. Supporting the initia- appropriate types of, and locations for including configuration and place- tive presently are Anne Arundel “living shorelines” treatments; and ment of original materials. County, several federal agencies, inde- facilitating the institutionalization of ! Changes in elevations and slope of pendent contractors, university re- living shoreline approaches through fill containment area, displacement of search groups and non-governmental contractors and shoreline management structural features (stone groins, environmental organizations. The over- policy makers. The ultimate desired sills, breakwaters etc.). all goal of the Living Shorelines Stew- outcome is to have: “Maryland and ardship Initiative is to improve water Virginia shorefront property owners ! Changes in shoreline profile quality and enhance habitat for living routinely consider and frequently nearshore, shore zone, bank erosion resources in the Chesapeake Bay choose living shoreline alternatives as or deposition on-site, updrift & through the shoreline management their preferred shoreline management downdrift areas. efforts of individual waterfront property treatment.” ! Design features in relationship to owners. Key strategies to reaching the These “softer” more natural shore- wave climate, reach characteristics, line treatments involve the use of marsh shore type and substrate composi- The Virginia Wetlands Report is a reestablishment, beach nourishment tion. quarterly publication of the Wetlands and low profile rock structures com- Program at the Virginia Institute of ! Variations in treatment type designs, bined with biotic elements such as Marine Science of the College of maintenance & other factors affect- marsh toe protection and shallow water William and Mary. Subscriptions are ing results. sills as well as the use of properly em- available without charge upon written ployed organic materials such as fiber request to: Wetlands Program, Virginia Biological Effectiveness Factors: logs. Besides attenuating shoreline Institute of Marine Science, P.O. Box erosion, these treatments facilitate ! Emergent wetland plant community 1346, Gloucester Pt, VA 23062 USA. natural coastal functions and processes characteristics species composition Address corrections requested. such as nutrient recycling, sand and (tide-range variable), width of marsh, Program Director: sediment deposition, the movement of percent cover, plant height. detritus within the littoral zone and the Dr. Carl Hershner ! SAV historical presence, species, Head, Wetlands Advisory Program: protection of the natural shoreline habi- percent cover, canopy height, flower- Thomas A. Barnard, Jr. tat. These treatments may not be appro- ing, maximum depth of distribution. Produced by: priate for all shorelines, high energy ! Associated fauna use of the site by VIMS Publication Center beaches for example, but where they can be utilized, the discerning property birds, reptiles, invertebrates etc. In this Issue: owner may benefit from reduced costs, ! Habitat suitability water quality (dis- Preserving the Bay’s creating or maintaining habitat and solved inorganic nitrogen and phos- Living Shoreline ................................ 1 conditions that contribute to maintain- phorus), epiphytic loading. Celebrating a Wetland Wildflower ing and restoring water quality along Seashore Mallow with important Chesapeake Bay habi- The Virginia Institute of Marine Kosteletzkya virginica ..................... 3 tats. Science (VIMS) has been funded by the Snakehead Invades The University of Maryland Center Keith Campbell Foundation for the Potomac River ................................... 4 for Environmental Studies (UMCES) Environment to conduct field surveys Dunkin .............................................. 5 Horn Pt. Lab has received funding from in Virginia focusing on the effective- New and Interesting Web Sites......... 6 Maryland Department of Natural Re- ness of existing low profile marsh toe Calendar of Upcoming Events .......... 6 sources and the Chesapeake Bay Trust protection structures identified through to conduct a detailed field assessment their Tidal Shoreline Permit Data Base. This report was funded, in part, by the and documentation of 8 shoreline ero- Virginia Institute of Marine Science The assessment team will use many of and by the Virginia Coastal Re- sion control projects in Maryland the same criteria, listed above, to de- sources Management Program of which incorporate marsh creation or velop a site-specific profile of each the Department of Environmen- protection as a key element of the de- marsh toe structure and photographic tal Quality through Grant sign. The team, which will also include #NA03NOS4190104 - Task #11 of the Na- exhibits that will be used to produce tional Oceanic and Atmospheric Administra- experts from Virginia and Maryland presentation materials for a spring 2005 tion, Office of Ocean and Coastal Resources funded by the Campbell Foundation, workshop. The workshop will be spon- Management, under the will evaluate a variety of factors that sored by the National Estuarine Re- Coastal Zone Management may vary from site to site. Factors to be Act, as amended. search Reserve System and the Center assessed may include: for Coastal Resources Management at The views expressed herein are those of the VIMS and should be of interest to ma- authors and do not necessarily reflect the Physical Effectiveness Assessment views of NOAA or any of its subagencies or rine contractors, waterfront property DEQ. Factors: owners, environmental