SECTION 4: Management Measures

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## 4.3. H ABITAT 

## A SSESSMENT



### Management Measure Description

The construction of a marina in any waterbody can disrupt aquatic habitats. This management measure is important because of the value of protecting natural habitats so they continue to provide food and recreational opportunities for people, as well as food and shelter for plants and animals, and so their roles in the ecological health of waterbodies are protected. Past waterfront development has adversely affected many waterbodies, but our knowledge of ecology has increased. We now realize the importance of healthy aquatic habitats to both our health and the

overall health of our waterbodies. Efforts to

decrease the introduction of invasive and exotic species have increased, and minimizing pollution in waterbodies is widely accepted as a sound ecological and economic practice. In many cases, federal and state laws require analyses of the potential impacts on the natural environment before projects begin. This management measure focuses on marina siting and design and extends to assessments of how marinas can incorporate natural habitats into their siting and design.

When well designed and cared for, marinas can be a valuable habitat for plants and animals that are adapted to quiet, sheltered waters. Regardless of the type of waterbody on which a marina is to be constructed, siting it where its development or operation will diminish the biological or economic value of the surrounding habitats should be very carefully considered, especially if the potential site is near locations that have been given specialdesignations by local, state, or federal governments. Such habitats might be fish spawning areas, shellfish harvesting areas, designated wetlands, beds of submerged aquatic vegetation (SAV), or areas where threatened or endangered species are known to occur. If a marina is properly designed and located, aquatic plants and

animals should be able to continue to use the marina waters for the same activities (e.g., reproduction or feeding) that occurred in the waters before the marina’s presence.

Marinas that have been operating for a while can provide sheltered, quiet waters for plants and animals that prefer this type of environment or for animals that need this type of environment during specific life stages, such as spawning. Where the surrounding environment has been developed and offers little in the way of natural habitat, such as in an urbanized waterfront district, a marina might provide a refuge for many species. A pollution prevention and control program, based on the management measures presented in this guidance, can help maintain or improve water and habitat quality for aquatic species.

The locations of all important aquatic and riparian habitats in a locality or waterbody might not be known. A visual survey by a biologist may be appropriate before any marina construction or expansion begins, and a specialist in aquatic

habitat restoration can be contacted if marina management is considering modifying the marina to create good aquatic habitat in the marina basin. Geographic information systems (GIS) are being used increasingly to map biological resources in many states and show promise as a method ofconveying important habitat and other siting information to marina developers and environmental 

### Management Measure for Habitat Assessment:

**Site and design marinas to protect against adverse effects on shellfish re sources, wetlands, submerged aquatic vegetation, or other important riparian**  **and aquatic habitat areas as designed by local, state, or federal governments.**4-20 National Management Measures Guidance

protection agencies. The state department of environmental protection or natural resources can be contacted for this type of information.



### Applicability

This management measure is applicable to new and expanding marinas where site changes might affect wetlands, shellfish beds, aquatic vegetation, or other important aquatic resources or habitats.



### Best Management Practices

♦ Conduct habitat surveys and characterize the marina site, including identifying any exotic or invasive species.

The first step in constructing a marina that will becompatible with the surrounding natural environment or expanding or modifying an existing

marina to create a more natural environment is to characterize the environment of the proposed siteor operational marina. Before marina development or expansion, critical or unique habitats, such as beds of submerged vegetation and shellfish beds, should be identified. The importance of the area that will be affected by development to aquatic organisms for spawning, feeding, or their

overall survival should be assessed within the context of the entire waterbody (Figure 4-6). Equally as important, exotic plants and animals that could be problematic for marina operation

should be identified. Table 4-1 lists some common exotic and invasive aquatic species in the United States. Once the site has been characterized, marina development or expansion can proceed in a way that minimizes adverse effects on aquatic

life and habitats.



### ♦ Assess habitat function (e.g., spawningarea, nursery area, feeding area) to minimize indirect effects.

An area proposed for marina development or expansion could be used seasonally by fish or other animals. Animals use special areas of many coves, shorelines, beds of submerged vegetation, rivers, streams, and estuaries for short periods of time—from a few nights to weeks—for particular life functions such asmigration, spawning, and rearing young. Marinas can accommodate these special, short-term uses if marina designers and managers are aware of the need for the areas and the marina is

built with the needs in mind.



### ♦ Use rapid bioassessment techniques to assess effects on biological resources.

Rapid bioassessment techniques, where they have been developed, provide cost-effective biological assessments of potential marina development sites. Rapid bioassessment uses biological criteria (usually invertebrate and fish populations) as indicators of the condition of a habitat. To apply rapid bioassessment to a marina development siteor an operating marina, select biological communities at the proposed site or the operational marina are compared to the same biological communities at an undisturbed site in the same waterbody or a similar one. The biological health of the proposed

site or marina basin is rated based on how favorably the invertebrate or fish communities there compare with those of the undisturbed site. Scores from rapid bioassessments are useful for determining whether a site is stressed by pollution or other factors, such as habitat alteration. Rapid bioassessment protocols for macroinvertebrates

and fish in freshwater streams and rivers are being developed by many states, and a document

on them is available from EPA at the web address Figure 4-6. Habitat assessment was used at Elliot Bay Marina (Washington) to design the marina to work with natural habitat function. Wide openings between rock groin-type breakwaters, docks, and beach give easy access to migrating juvenile salmon leaving Puget Sound, while providing good water circulation and tidal changes inside the marina basin. A man-made 1,500-foot-long sandy beach has replaced lost habitat, providing a feeding ground for young salmon. Schools of young salmon and herring move throughout the marina basin (USEPA, 1996: Clean Marinas—
Clear Value ).SECTION 4: Management Measures

4-21Table 4-1. Common Invasive and Exotic Species of the United States4-22 National Management Measures Guidance

< http://ww w .epa.gov/owowwtr1/monitoring/rbp/

index.html >.



### ♦ Redevelop waterfront sites that have been previously disturbed and expand existing

marinas.

Waterfront areas that have been previously used for industrial or military purposes might make good locations for new marinas because they have been developed before, usually have all thenecessary infrastructure, and minimize disturbances to aquatic habitats. Many sites suitable for recreational boating facilities may be located in existing urban harbors where shorelines have been modified by bulkheading and filling. Theadverse environmental consequences of redevelopment are usually minimal, and redevelopment can improve water quality, expand upland habitats, beautify and expand shorelines, and provide additional public access.

Waterfronts that are converted from waterdependent uses, such as marinas and recreational boating, to non-water-dependent uses, such as residences, office space, and shopping areas,reduce the availability of sites for marina development. To protect against such conversion in areasthat contain important habitat, a state may purchase the property or the development rights from existing water-dependent uses. To preserve an existing marina, for example, a state government could pay the difference between the marketvalue for other non-water-dependent development, such as for condominiums, and the waterdependent value of the marina to the marina owner, and receive in return a guarantee that the

site would not be converted to a non-waterdependent use. States can use this method to retain sites suitable for marinas, maintain access for boating uses of the waterways, prevent conversion to other uses, and reduce the base value for property taxes.



### ♦ Consider alternative sites where adverse environmental effects will be minimized or positive effects will be maximized.

An analysis of alternative sites (sites other than the one proposed) can be used to demonstratewhich site is the most economically and environmentally suitable. Analysis of alternative sites and designs has been effectively used to reduce the effects of development (including effects on tidelands, stream courses, shorelines, wetlands, and submerged aquatic vegetation) at many proposed marinas, and to find sites with flushing

characteristics better than those at the sites initially proposed.

Many marinas built on freshwater lakes and rivers over the past two decades are located on what are known as brownfields, or shoreland that had been modified and seriously abused by previous industrial facilities. Usually, these areas support little to no natural vegetation or habitats when they are first converted to marinas. The marinas

have turned these areas into recreational sites and public access points and have provided sheltered areas with protected shorelines, where natural vegetation has been able to reestablish itself.



### ♦ Create new habitats or expand habitats in

the marina basin.

Almost any surface placed in coastal or inland waters, and especially rough surfaces—including rocks, piles, piers, and floats—quickly becomes home to a host of plants, animals, and bacteria. The submerged parts of breakwaters, piers, and floating docks are excellent examples of this kind of “created” habitat. The plants that colonize these surfaces provide refuge for a variety of invertebrates and are a good source of food for juvenile fish, which in turn can attract sport fish (Figure 4-7).



### ♦ Minimize disturbance of riparian areas.

Riparian areas are the narrow areas along the banks of rivers, streams, lakes, ponds, reservoirs, The Hammond Marina (Indiana) was
built on a derelict brownfield industrial site with a steel mill slag shoreline. The area is now a pleasant and protected boating facility with an attractive public access area, and it is popular as a sportfishing site. The local economy has benefitted from the redevelopment, and shorelines, upland habitats, and aquatic habitat at the site have been tremendously improved (USEPA, 1996:
Clean Marinas —Clear Value ).SECTION 4: Management Measures

4-23 and wetlands. They may be vegetated, or may be beaches or rocky areas. Vegetated riparian areas

extract nutrients from runoff from the land as it moves toward the waterbody and from the water that constantly circulates along the banks of thewaterbody. The nutrients make them very productive habitats, with biodiversity and biomass typically higher than those of adjacent uplands. Many processes important to the health of waterbodies occur in vegetated riparian areas, including the following:

• Large quantities of nutrients are absorbed as

waters pass through riparian areas.

• Eroded soils and other pollutants are filtered

out of the water and absorbed by riparian vegetation. • Nutrients are modified from forms that can’t be used by aquatic organisms to forms they can readily use.

• The vegetation in riparian areas serves as a

refuge for species for nesting, hiding from predators, and foraging.

Beaches and rocky shorelines also provide habitatvariety and are important to many aquatic organisms. Because of the importance of all types of riparian areas to the general health of waterbodies, minimizing disturbances to them during marina development can be beneficial. Creating favorable conditions for the presence of riparian or wetland areas within a marina basin might be an effective, low-cost way to improve water quality in the basin or increase habitat diversity in the basin, depending on site conditions and space limitations.



### ♦ Use dry stack storage.

An alternative to building new docks for expanding boating access and marina capacity is to build dry stack storage facilities, in which many boats are stored on vertical stands on very little land. Boats stored in dry stack storage do not leak antifoulants to the water and can be more easily maintained on land in protected hull maintenance areas, providing less opportunity for spillage directly to surface waters. Dry stack storage has minimal environmental effects, and where zoning restrictions permit it, it is an appropriate means to increase public access to waterways.

BMP Summary Table 3 summarizes the BMPs for Habitat Assessment mentioned in this guidance. Figure 4-7. Oak Harbor Marina sign. Oak Harbor Marina (Washington) has used its marina waters to
raise salmon for release. Volunteers built salmon pens, and more than 420,000 salmon have been released as a result of the program. Deep River Marina (Connecticut) was the site for a 3-year federal/state stocking program for Atlantic salmon. The Puerto Rico Department of Natural Resources’ Fisheries Office is located in Puerto del Rey Marina (Puerto Rico) and uses part of the facility’s clean waters for an injured sea turtle rescue and recovery program (USEPA, 1996; Clean Marinas–Clear Value).4-24 National Management Measures GuidancealterationSECTION 4: Management Measures

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