COSTS OF WATER TREATMENT DUE TO DIMINISHED
WATER QUALITY: A CASE STUDY IN TEXAS
David Dearmont
Administrator, Research Division
Nebraska Department of Revenue
301 Centennial Mall South
PO Box 94818
Lincoln NE 68509-4818
Bruce A. McCarl
Professor, Department of Agricultural Economics
Texas A&M University
College Station TX 77843-2124
Deborah A. Tolman
PhD student, Department of Environmental Sciences and Resources
Portland State University
P O Box 751
Portland OR
97207-0751
October, 1997
Draft of paper in Water Resources Research, 34(4), 849-854, 1998.
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CHEMICAL COSTS OF WATER TREATMENT DUE TO DIMINISHED
WATER QUALITY: A CASE STUDY IN TEXAS
Abstract
The cost of municipal water treatment due to diminished water quality represents an important
component of the societal costs of water pollution. Here, the chemical costs of municipal water
treatment are expressed as a function of raw surface water quality. Data are used for a three year
period for 12 water treatment plants in Texas. Results show that when regional raw water
contamination is present, the chemical cost of water treatment is increased by $95 per million gallons
from a base of $75. A one percent increase in turbidity is shown to increase chemical costs by one
fourth of a percent.
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COSTS OF WATER TREATMENT DUE TO DIMINISHED
WATER QUALITY: A CASE STUDY IN TEXAS
Introduction
The cost of municipal water treatment due to diminished water quality represents an important
component of the societal costs of water pollution. Efficient management of water supplies must
balance the costs of cleaning, using, or avoiding use of polluted water. The marginal cost of improving
raw water quality generally should not exceed the marginal benefit of such an improvement. An
increase in municipal water quality standards, holding other things constant, will increase the benefit
from improved raw water quality, but will also increase treatment cost. This study provides information
on the marginal municipal costs of treating polluted water as affected by pollutant