Water Quality
Assessment and Regulation

Water quality
Source: USGS

In order to determine the management techniques for a specific waterway in respect to water quality, it is necessary to know the current and desired water quality levels for the waterway; we cannot solve a problem if we cannot first identify the problem. As such, it is necessary for each country to establish a system of water quality monitoring and a set of regulations regarding water quality levels.

The water quality regulations should set:

  1. minimum standards for levels of various contaminants
  2. biological standards for water quality
  3. an anti-degradation policy (i.e. a waterway's state cannot decrease in quality)

The water quality should be measured both by concentrations or levels of contaminants as well as by biological measures. The use of biological, in addition to chemical, measures is necessary because biological measures are better able to detect brief events. For example, spilled chemicals could wash down a river before a chemical measurement could be performed to detect them, but the presence of dead fish or other organisms would still indicate that something had happened.

Furthermore, a permitting process for activities that are likely to cause environmental harm (such as earthmoving operations or construction and discharges into waterways) should be instituted so that the environmental risks may be assessed and so that plans for development can be made sensitive to environmental needs. The permitting process allows the government to have a say in how the activity is carried out and to set regulations specifically for that project.

As indicated by the WHO (World Health Organization) in their report on water quality assessments, the choice of which water quality parameters to use can depend on the use of the waterway or on the expected pollution sources. We recommend that water quality be tested regularly in estuaries and major waterways that drain directly to the ocean; in all cases the water should be clean enough to support aquatic life. Initial attention should be given to the largest waterways and those that are expected to be highly polluted (i.e. those traveling through an industrial sector or city), so that problem areas and areas of great importance are addressed first. Furthermore, by testing a larger body, the effects of tributary streams are taken into account, as those contaminants will still be present in the larger waterway. These tests should measure the following parameters recommended by the WHO for aquatic ecosystems (see chart below). From the data collected, the state of the waterway can be assessed and various solutions can be implemented.

Temperature Suspended Solids Turbidity/transparency Conductivity
Total dissolved solids pH Dissolved oxygen Hardness
Chlorophyll A Ammonia Nitrate/nitrite Chemical oxygen demand
Biochemical oxygen demand Cyanide Heavy metals Arsenic and selenium
Oil and hydrocarbons Organic solvents Phenols Pesticides
Surfactants     Source: Chapman, 1996

For parameters that do not meet standards, the source of the contamination should be identified. For point source pollutants that were discharged before the implementation of the law, the perpetrators should be notified of their infractions and ordered to stop the discharges. Polluters should also be given a time frame (suggested time is a year) in which the pollutant's effects must be mediated in order for business to continue. For point source pollutants that were discharged after the implementation of the law, the perpetrator must pay a fine to cover the costs of the environmental damage.

For non-point source pollutants, there are several ways to reduce the effects. Non-point source pollutants are carried into the water by runoff. Water travelling over the land picks up soil and other contaminants and carries them into the waterway. To reduce the concentrations of these contaminants, maintenance and reestablishment of riparian buffers (vegetative areas alongside waterways) is an effective solution, as is maintaining and reestablishing wetlands.

Biological indexes and standards are independent of the pollutant source; they merely categorize the species composition of an area by abundance of species sensitive to pollutants or environmental disturbance, abundance of species somewhat sensitive, and abundance of species tolerant of such disturbance. The complexity of the indexes can vary, but the underlying principle is that a healthy waterway has a variety of species of all three categories, and impaired waterways have a smaller variety and the species that are present fall into the latter categories. If biological monitoring is considered too expensive, it is possible to choose a method of sampling that is less expensive by sampling fish and large macroinvertebrates, since effects will eventually manifest at these levels; studies by the EPA have shown these studies to be more cost effective (EPA, 1988). However, it is important to note that small amounts of contaminants will affect the young and most sensitive organisms first, which may not necessarily be the fish. Monitoring of the habitat may also be valuable in assessing changes.

The EPA's guide to establishing a biological index shows an example of how such a system may be implemented (http://www.epa.gov/waterscience/biocriteria/States/estuaries/estuaries.pdf).

Discharges into waterways cannot be allowed to change the quality of water to levels below those specified in the standards. Furthermore, the non-degradation policy forbids decline in the quality of water in a waterway that exceed the minimum standards. To effect this, before a discharge is to be implemented, water quality measures should be taken to determine the baseline water quality of the waterway; note that water quality sampling parameters should be expanded or modified to accommodate pollutants that are likely to result from the industry in question. Both chemical and biological indexes will be used. Subsequent water quality measurements should be taken multiple times per year both above and below the discharge site; emphasis will be given to the biological indexes as it is more robust to temporal change, as aforementioned. If the discharge is found to be in the "pollutant" range, the company will be fined an amount sufficient to cover the environmental damage and proportional to the damage caused; the fine will be used to remediate the damage caused by the pollutant. Non-discharge offenses (i.e. dumping by a citizen or other unplanned discharges) will be dealt with in the same manner.

However, extraction of materials from ecosystems is also an issue in coastal zone management. Extraction of sediments or other mining operations causes severe changes in substrate composition and the overall habitat, not to mention the possible pollutant re-suspension involved in these operations (i.e. of sediments). Extraction of water (either surface water extractions or ground water extractions, as from wells) itself also changes the aquatic ecosystem in many ways--both from a physical and chemical standpoint. Information about the effects of dams on water quality is here.

To address these aspects of regulation, research needs to be conducted to the determine the relationship between the status of the physical environment and the functioning of the ecosystem. For example, with dredging or sediment extraction, the functional role of the substrate formations should be investigated to discover if the extraction would negatively impact critical spawning or other ecosystem services and if any predicted damages can be redressed. Findings of such studies should then be applied to minimize disturbance to the environment if the activity still needs to occur; the principle of "avoid, minimize, compensate" as advocated in the U.S. policy towards wetlands applies here.

For water withdrawals (or large water discharges) we propose the use of IFIM (Incremental Flow Incremental Methodology) to evaluate the effects of the withdrawal before it takes place, so that planning and permitting can take place before withdrawals begin. The IFIM model can be used to predict how changes in flow will affect various other water quality parameters like temperature and how these changes will affect fish populations (Young, 1997). The results of the model can be used in the permitting process to make initial suggestions and limitations; however, regulation should be elastic enough so that withdrawal limitations can be changed if harm is observed. Special attention should be given to processes which may fundamentally alter sediment and nutrient transport, as alterations can negatively impact estuarine and lower waters to a great extent, as discussed in the page on dams.

Shipping Regulation

Shipping is a major source of contamination in coastal areas. Ballast water, for example, is a major transport mechanism for invasive species, while oil tankers can spill their cargoes. Shipping regulations should be created to minimize these risks.

Invasive Species Transport

Invasive species transport
Sediment in a ballast tank; this sediment can host aquatic invasives. Source: NOAA
Ships traveling internationally should be required to exchange their ballast water at sea, past the continental shelf. The salinity and temperature differences between fresh or estuarine waters and the open ocean are great enough to kill most potential invasives. (Portland State University, 2006)

Future research should look explore alternative forms of ballast that minimize the risk of invasive transport.

However, many invasive species travel via other means---including intentional release such as the introduction of the red-eared slider in the United States (PA's 10 Least Wanted). To prevent this, strict trade regulations should be placed that prohibit the transport of non-native species between countries and between waterways within the same country to another (PA's 10 Least Wanted).

Tanker Spill Prevention

Regulations should be created to restrict which types of boats may carry hazardous materials into or on a nation's waters. The regulations should include requirements for hull strength and features to prevent a spill if the ship runs aground or hits rocks. Ships should also be required to have up-to-date communications and navigation equipment. Shipping lanes for oil tankers that are safer or easier to navigate would also be beneficial. Ships should also be required to have an emergency response plan for the event of an oil spill that needs to be approved by the State whose waters are traversed. Appropriate government agencies should also have oil spill response plans. Finally, legislation should be passed that assigns responsibility for oil spills to the entity possessing the oil at the time of the spill. (adapted from the EPA's Oil Pollution Prevention and Response Final Rule, 2002)