Various reservoirs have been serving as the most important drinking water
sources in Zhejiang Province, China, due to the uneven distribution of precipitation and
severe river pollution. Unfortunately, rapid urbanization and industrialization have been
continuously challenging the water quality of the drinking-water reservoirs. The identification
and assessment of potential impacts is indispensable in water resource management and
protection. This study investigates the drinking water reservoirs in Zhejiang Province to
better understand the potential impact on water quality. Altogether seventy-three typical
drinking reservoirs in Zhejiang Province encompassing various water storage levels were
selected and evaluated. Using fifty-two reservoirs as training samples, the classification
and regression tree (CART) method and sixteen comprehensive variables, including six
sub-sets (land use, population, socio-economy, geographical features, inherent characteristics,
and climate), were adopted to establish a decision-making model for identifying and assessing
their potential impacts on drinking-water quality. The water quality class of the remaining
OPEN ACCESS
Int. J. Environ. Res. Public Health 2014, 11 6070
twenty-one reservoirs was then predicted and tested based on the decision-making model,
resulting in a water quality class attribution accuracy of 81.0%. Based on the decision rules
and quantitative importance of the independent variables, industrial emissions was
identified as the most important factor influencing the water quality of reservoirs; land use
and human habitation also had a substantial impact on water quality. The results of this
study provide insights into the factors impacting the water quality of reservoirs as well as
basic information for protecting reservoir water resources.