pH
Overview
The pH of an aqueous solution is controlled by interrelated chemical reactions that produce or consume hydrogen ions. The pH of a solution is a measure of the effective hydrogen-ion concentration activity. Solutions having a pH less than 7.0 are described as acidic; solutions with a pH greater than 7.0 are described as basic or alkaline.
Water-quality standards and criteria are developed by the States, approved by the U.S. Environmental Protection Agency (USEPA), and then promulgated (passed into law) as standards by each State. Graphs on this website allow comparison of measured and computed data to these standards and criteria by plotting them as straight lines. When evaluating data to decide whether water quality is suitable for the intended use, viewers are cautioned to consider the uncertainty associated with these computed data.
Water-quality Standards and Criteria
Maryland minimum contact recreation criterion: 6.5 std units
A minimum water-quality criterion of 6.5 standard units has been defined by Maryland Department of the Environment. This criterium is for contact recreation and protection of nontidal warmwater aquatic life.
Source: Code of Maryland Regulations (COMAR) 26.28.02.03-3 (view online)
Maryland maximum contact recreation criterion: 8.5 std units
A maximum water-quality criterion of 8.5 standard units has been defined by Maryland Department of the Environment. This criterium is for contact recreation and protection of nontidal warmwater aquatic life.
Source: Code of Maryland Regulations (COMAR) 26.28.02.03-3 (view online)
Stations That Measure or Compute Continuous pH
Click a station to view measurements of pH.