Thermal enhancement of stormwater runoff by paved surfaces

A methodology for predicting the thermal enhancement of stormwater runoff f rom paved surfaces is documented for a test facility in Kingston, Ontario, Canada. Prediction of runoff temperature is based on TRMPAVE, a mathematica l model that was developed using a thermal energy balance approach and the one-dimensional heat equation to predict the surface temperature and temper ature gradient in asphalt during dry-weather and wet-weather periods. Runof f temperature is then estimated as a Function of rainwater temperature and surface temperature of the asphalt. In order to supplement wet-weather data l a number of simulated rainfall events H-err generated over a rest plot to help develop, calibrate and verify the wet-weather model. Computer simulat ions For both dry and wet-weather periods compared well with measurements o f temperature from the test plot. In addition, the average temperature of r unoff contributed by the entire parking lot area was cooler than the averag e temperature of runoff from the test plot, but both values were higher tha n runoff from the upstream catchment. In light of the results obtained, TRM PAVE can be used to predict thermal loading from impervious areas. (C) 2000 Elsevier Science Ltd. All rights reserved.