Earthplace's Harbor Watch program will offer a four-week workshop on measuring the health of a stream or river from 9:30 a.m. to noon Saturdays, Oct. 13, 20 and 27, and Nov. 3, at its facility, 10 Woodside Lane.

The program will look at the kinds of parameters a scientist might look at and why people should be concerned, according to a release.

Topics on physical, chemical, bacteriological and macro-invertebrate parameters, highlighting aquatic insects, will be explored. Hands-on water testing will also be highlighted, with an emphasis on nutrients and how field measurements can lead to the understanding and detection of pollution.

The correct procedures for sampling and the proper techniques for measuring dissolved oxygen, pH, conductivity, ammonia-nitrogen, nitrate-nitrogen, fecal coliform bacteria and other indicator bacteria forms will be included. A discussion on field and laboratory instrumentation will also be highlighted.

Handout materials and refreshments will be included.

The fee is $45 for members and students, $75 for nonmembers. To register, call 203-227-7253.