Glossary beginning with D

terms for which definitions are available


a man-made barrier, together with its appurtenant works, constructed for the purpose of impounding or storing water or another fluid or semifluid


Pennsylvania Department of Conservation and Natural Resources

defective lateral

a plumbing problem in which a lateral pipe is damaged, potentially leading to sanitary waste in a storm sewer and the receiving water body


the volume of runoff that is captured and released into the waters of this Commonwealth at a controlled rate

detention basin

an impoundment designed to collect and retard stormwater runoff by temporarily storing the runoff and releasing it at a predetermined rate; designed to drain completely soon after a rainfall event and become dry until the next rainfall event


any human-induced change to improved or unimproved real estate, whether public or private, including, but not limited to, land development, construction, installation, or expansion of a building or other structure, land division, street construction, and site alteration such as embankments, dredging, grubbing, grading, paving, parking or storage facilities, excavation, filling, stockpiling, or clearing


flow; a measure of the volume of water flowing through a defined area in a given time. Discharge is often abbreviated as Q, and measured in cubic feet per second (cfs)

drainage area

the area of land that drains to a particular body of water or site on a waterbody; also see 'catchment'