Temperature of ground water at Philadelphia, Pennsylvania, 1979- 1981

Water-Resources Investigations Report 84-4189



Anthropogenic heat production has undoubtedly caused increased ground-water temperatures in many parts of Philadelphia, Pennsylvania, as shown by temperatures of 98 samples and logs of 40 wells measured during 1979-81. Most sample temperatures were higher than 12.6 degrees Celsius (the local mean annual air temperature), and many logs depict cooling trends with depth (anomalous gradients). Heating of surface and shallow-subsurface materials has likely caused the elevated temperatures and anomalous gradients. Solar radiation on widespread concrete and asphalt surfaces, fossil-fuel combustion, and radiant losses from buried pipelines containing steam and process chemicals are believed to be the chief sources of heat. Some heat from these and other sources is transferred to deeper zones, mainly by conduction. Temperatures in densely urbanized areas are commonly highest directly beneath the land surface and decrease progressively with depth. Temperatures in sparsely urbanized areas generally follow the natural geothermal gradient and increase downward at about that same rate.

Study Area

Additional publication details

Publication type Report
Publication Subtype USGS Numbered Series
Title Temperature of ground water at Philadelphia, Pennsylvania, 1979- 1981
Series title Water-Resources Investigations Report
Series number 84-4189
DOI 10.3133/wri844189
Year Published 1986
Language English
Publisher U.S. Geological Survey
Contributing office(s) Pennsylvania Water Science Center
Description iv, 14 p.
Country United States
State Pennslyvania
City Philadelphia
Online Only (Y/N) N
Additional Online Files (Y/N) N