Assessing Water Quality

Online Dive Planning Tools

Polluted waters are a concern for both recreational and professional divers. Potential pollution exposure led the U.S. Environmental Protection Agency (EPA) to upgrade protective measures for its dive teams, such as keeping the diver completely dry and implementing the use of decontamination, medical monitoring and immunizations. As pollution becomes an ever-increasing problem, recreational divers should also know how to identify and assess polluted waters. There are several online tools available for planning a polluted water dive or ensuring the dive you are planning is not a likely polluted water dive.

In waters near metropolitan areas, bacteria in the water column can be a problem from a variety of sources, including pet waste and sewage overflows. EPA's Beach Environmental Assessment and Coastal Health Program (BEACH) provides regular bacterial counts at popular marine and Great Lakes recreational sites. Information on sewer discharge location, overflow frequency and publicly available bacterial count information can be a valuable dive planning tool.

In addition, chemical and biological contaminant trends in the water column and sediment are available through NOAA's Mussel Watch Program. Outfalls, which are places where drains or sewers empty into a body of water, can also discharge a variety of harmful chemicals to the dive site. EPA's Envirofacts database presents outfall location and data that can be of use in planning for worst-case water quality at a particular dive site. You can also obtain a list of chemically impaired water bodies from EPA's 303d list. Even use of up-to-date navigation charts can provide some level of outfall information. Internet searches on fish advisories may also help indentify polluted waters.

It is important to note, many Superfund Sites are near or include bodies of water, which typically must be treated as polluted water dives. Most Superfund sites have some online chemical data available on the water column and/or sediment.

If specific chemical contaminants are known or suspected on a site, a hazard analysis should be included in the dive plan to address potential exposure pathways and identify specific equipment or procedures necessary to minimize risk factors. Several online chemical data bases, such as EPA Integrated Risk Information System (IRIS), NOAA CAMEO Chemicals Database of Hazardous Materials, Center for Disease Control (CDC) NIOSH Pocket Guide to Chemical Hazards or CDC Agency for Toxic Substance and Disease Registry, contain useful information on chemical properties and chemical hazards to human health.

Drysuit manufacturers can also be consulted to obtain permeation data for known or suspected contaminants. If decontamination solutions (soaps, detergents, biocides) are necessary, the material safety data sheets (MSDS) or the manufacturer's web site should be consulted to assess toxicity and biodegradability. Check with local jurisdictions before discharging any solutions into a water body; in most cases any rinse solution other than potable water must be collected and treated via a publicly owned treatment works. EPA has shown a potable water rinse on decontamination compatible gear is effective for the removal of the majority of microbes.

EPA often uses protective gear and protocols when diving known or suspected contaminated areas (e.g., hazardous waste sites, urban areas, ports/harbors, sites with fish consumption advisories, or sites with a high number or close proximity of outfalls) rather than relying on real-time water analyses as levels can change with the turn of a valve. To safely dive in chemically or biologically polluted water, divers must receive proper training to recognize and mitigate hazards. Online tools will help divers assess what contaminants may be present at the dive site, what effect these contaminants may have on the diver or the diver's equipment, and what equipment and decontamination procedures may be necessary to protect the diver.
For more information on polluted water diving available from EPA:
A note from DAN: As a recreational diver, these tools should be used to assess potential dive sites and avoid diving in contaminated waters. For public safety dive teams who are properly trained and equipped for diving in contaminated waters, these tools are great assets for risk assessment and management. To learn more, read "Microbial Hazards."