Glossary of Water and Wastewater Terms

A B C D E F G H I J K L M N O P Q R S T U V W Y Z Symbols and Numbers

5 random terms from our glossary

Manhole Inflow

Surface waters flowing into a manhole, usually through the vent holes in the manhole lid.


Plastic tubes shaped like pillows that contain exact amounts of chemicals or reagents. Cut open the pillow, pour the reagents into the sample being tested, mix thoroughly, and follow test procedures.


An area set aside for manufacturing and industry.

Initial Backfill

Backfill extending from the springline or horizontal centerline of a pipe to a point above the top of the pipe. This zone provides some pipe support and helps to prevent damage to the pipe during placement of the final backfill. Also see BACKFILL and FINAL BACKFILL.

Heat Sensor

A device that opens and closes a switch in response to changes in the temperature. This device might be a metal contact, or a thermocouple that generates a minute electric current proportional to the difference in heat, or a variable resistor whose value changes in response to changes in temperature. Also called a temperature sensor.