Less Common Criteria – More Common Threats

Unfortunately, some of the most pervasive problems in our waters are not commonly addressed in water quality standards by either narrative or numeric criteria. The following criteria are needed to describe fully the state of watershed health.

Nutrient criteria

Very few states have developed nutrient criteria. EPA has developed nine documents to address nutrient criteria in different water bodies in various areas of the country.
(http://www.epa.gov/waterscience/criteria/nutrient/ecoregions/#docs)

Sediment criteria

Some States have established sediment criteria using numeric total suspended solids and turbidity measures, as well as narrative measures that prohibit “unnatural” levels of sediment in waterbodies. (http://www.epa.gov/waterscience/criteria/sediment/index.htm)

Toxic contaminant criteria

Many states have developed numeric and narrative criteria for toxic pollutants. EPA released guidance for several priority pollutants a few years ago. States are supposed to have developed criteria that are consistent with this guidance.
(http://www.epa.gov/waterscience/criteria/wqcriteria.html)

Flow criteria

Four states (Kentucky, New Hampshire, Virginia, Vermont) have narrative flow criteria that call for the protection of adequate flows to support existing and designated uses.

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