SECTION 4: Management Measures

4-13 

## 4.2. WATER 

## Q UALITY 

## A SSESSMENT



### Management Measure for Water Quality Assessment:

**Assess water quality as part of marina siting and design**

**.**



### Management Measure Description

Water quality can be assessed as a part of newmarina development or expansion. This management measure is useful for determining the suitability of a location for marina development, the best marina design for ensuring good water quality, and the causes and sources of water quality problems.

When planning for a new or expanded marina site, state water quality management agencies can

be contacted for available information. A water quality assessment consists of taking samples of water from a waterbody; testing them for one or more criteria, usually chemical and physical characteristics and the presence of pathogenic organisms; and comparing the results to accepted standards of water quality. Historically, state water quality assessments have focused on testing the dissolved oxygen concentration of water and the presence of pathogen indicators, such as fecal coliform bacteria ( Escherichia

coli ) and enterococci. Other tests, such as measurement of water temperature or Secchi disk depth (Figure 4-3), are used as well.

The dissolved oxygen concentration in water is used as an indicator of the general health of an aquatic ecosystem. A good concentration of dissolved oxygen (typically about 6 milligrams/liter [mg/L], but “good” can vary from waterbody to waterbody) can indicate that there’s enough oxygen for fish to breathe and aquatic plants to photosynthesize, and there’s a good exchange ofgases between the waterbody and the atmosphere. A low dissolved oxygen concen-tration, or a level below what is normal for the waterbody, might indicate that there is too much decaying organic matter in the water or that a film of oil or other substance is on the surface preventing an exchange of gases with the atmosphere, either of which could be due to nonpoint source pollution.

Pathogenic organisms in the water indicate the potential for public health problems. Pathogens are contained in human and animal fecal waste, and they can cause illness. Tests for these water quality criteria can be used to determine the condition of a site where a marina is proposed to be developed.

Federal, state, and municipal agencies routinely test the water of coastal and estuarine waters, lakes, and reservoirs, especially if there is a lot of recreational use of the waterbody and protection of public health is important. Results of the tests can be obtained by calling the agency that does the testing (e.g., state department of natural resources or environmental protection).

Figure 4-3. The Secchi disk is a simple and useful tool for monitoring long-term trends in water quality.4-14 National Management Measures Guidance



### Applicability

This management measure primarily applies to the design of new and expanding marinas.



### Best Management Practices

Monitoring can serve many purposes, such asdetermining the ambient quality of water, determining the extent or causes and sources of a water quality problem, analyzing trends in water quality, and measuring the effectiveness of management practices used in the marina. Modelingis appropriate for comparing the effects of different options, such as predicting the water quality that would result from different marina designs before actual construction or the effects of various marina designs on water circulation in a marina basin before a planned expansion. In areas of known good water quality, monitoring might not be needed for small marina developments. The BMPs described here are useful for major developments or expansions so that sufficient water quality measurements are made at a site to ensure that existing conditions are not significantly altered.

When considering monitoring water quality at a marina, consider that results indicating a waterquality problem exists at a marina do not necessarily mean that the marina is the source of the problem. Marinas often are located where theirwater quality reflects other activities in a watershed, lake, or river. Determining of the source ofwater quality problems often involves a watershed-wide monitoring effort. See page 1-5 for

more information about EPA’s Watershed Approach.



### ♦ Use water quality sampling and/or monitoring to measure water quality conditions.

Water quality data for the waterbody on which a marina is located might be available. Many states or local agencies collect this information. A state agency of environmental protection, a local or regional water quality authority, a parks andrecreation department, USEPA, the U.S. Geological Survey, the U.S. Army Corps of Engineers, or a local university (such as a Sea Grant college) is potential source of water quality data. It will be useful to contact the state agency responsible for water quality data at the outset of a project to establish water quality objectives and to determine whether water quality data are available for the site. Comparing water quality data from the marina to water quality data collected by a state agency, for instance, would be best accomplished by using the same sampling strategy and analytical methods used by the state agency so that a comparison of the two sets of data will be meaningful (Figure 4-4).



### ♦ Use a water quality modeling methodology to predict postconstruction water quality

conditions.

Not all proposals for new or expanding marinas will require the use of modeling techniques to predict water quality characteristics. Numerical modeling can be useful, however, for studying the effects of different design alternatives and for selecting the design that best avoids or minimizes impacts on water quality.

Modeling techniques can be useful for predicting flushing time and pollutant concentrations in theabsence of site-specific data. A distinct advantage of numerical models over monitoring studies is the ability to perform sensitivity analyses. For instance, dissolved oxygen concentrations and flushing times can be predicted for a number of design options once data for the marina project have been entered into the model. Modeling can be an expensive undertaking, and the costs should be weighed against any anticipated benefits.

A professional marina designer would be the best person to consult regarding the feasibility and cost

EPA Region 4 completed an in-depth report on marina water quality. The primary focus of the study was to provide guidance for selecting and applying computer models for analyzing the potential water quality impacts (bothdissolved oxygen and pathogen indicators) of a marina. EPA reviewed a number
of available methods and classified them into three categories—simple methods, mid-range models, and complex models.
See Section 5.SECTION 4: Management Measures

4-15 of using models. Some models applicable to

marinas are reviewed in Section 5

.


### ♦ Monitor water quality using indicators.

Water sampling, water quality monitoring, and numerical modeling are not necessary in many cases to gather information about the health of a marina’s waters. Simple yet effective forms of monitoring that provide valuable information about the conditions in the water can be done by someone knowledgeable of the marina and the surrounding waterbody. Visual inspections of the abundance and appearance of aquatic plants in and around the marina, use of the marina and surroundings by ducks and geese, the appearance of bottom sediments, the general clarity of the water near docks, and the abundance of fish can provide all the information necessary to judge the health of the water (Figure 4-5). All of these

characteristics are indicators of the health of the waters. These types of inspections can be done during the course of daily operations by any

member of the marina staff at minimal cost to the marina. (See volunteer monitoring BMP below.) Done every year, these visual inspections lead to a good knowledge of the “normal” conditions in the marina and surrounding waterbody, and any changes will be apparent to the keen observer. When changes are noted, some limited water sampling can be done to determine what might

account for them if a local or state environmental management authority hasn’t already done this.



### ♦ Use rapid bioassessment techniques to monitor water quality.

Rapid bioassessment techniques can provide a cost-effective means to assess potential sites for marina development and to assess water quality in an existing marina basin. This technique is

discussed further under the Habitat Assessment
management measure.



### ♦ Establish a volunteer monitoring program.

Marinas can help involve their clientele and localcommunity in water quality issues and environmental protection at the marina by beginning a volunteer monitoring program. Across the country, private citizens are learning about water quality issues and helping protect the Nation’s water resources by becoming volunteer monitors. Volunteers analyze water samples for dissolved oxygen, nutrients, pH, temperature, and a host of other water constituents; evaluate the health ofstream habitats and aquatic biological communities; inventory streamside conditions and land uses in a watershed that might affect water quality; catalog and collect beach debris; and restore degraded habitats.

EPA’s Office of Water encourages citizens to learn about their water resources and supports volunteer monitoring because of its many benefits. Volunteer monitors build awareness of pollution problems, become trained in pollution prevention, help clean up problem sites, provide data for waters that might otherwise be unassessed, and increase the amount of water quality information available. Among the uses of volunteer data are delineating and characterizing watersheds,screening for water quality problems, and measuring baseline conditions and trends.

For more information, contact EPA’s Office of Wetlands, Oceans, and Watersheds, Monitoring Branch, or the monitoring branch of a regional EPA or state environmental protection office. EPA’s volunteer monitoring Web site is located at

< ww w .epa.gov/owow/monitoring/vol.html >. Figure 4-4. Cedar Island Marina (Connecticut) scallop monitoring. After the state of Connecticut declined a permit for expansion on the grounds that it would result in “destroying valuable marina life and habitat,” the marina began a program of water quality monitoring to prove the state wrong. The marina monitors temperature, salinity, dissolved oxygen, habitat, coastal birds, finfish, and scallop growth. The photo shows marina personnel checking scallop cages suspended below the docks. The marina has found better dissolved oxygen levels and lower fecal coliform bacteria counts than those reported for the town beach, and heavy metals do not accumulate in scallops grown at the marina (USEPA, 1996: Clean
Marinas—Clear Value ).4-16 National Management Measures Guidance

BMP Summary Table 2 summarizes the BMPs for Water Quality Assessment mentioned in this guidance. Figure 4-5. Biological assemblages used for lake monitoring.SECTION 4: Management Measures

4-174-18 National Management Measures Guidance