Drought Vulnerability of Illinois' Community Surface Water Systems - Vulnerability, Illinois State Water Survey

Drought Vulnerability Classification

At-Risk System – There is greater than a 10% probability that the current system would not be able to provide the community’s current rate of water demand through a severe drought similar to the drought of record.

Drought Adequacy Description

If a drought similar to the 1962-1964 drought of record were to recur today, it is estimated with 50% confidence that the current system would be able to support a demand of 0.29 mgd (the mid- or best yield estimate). It is estimated with 90% confidence that the current system would be able to support a demand of 0.14 mgd. Because the system would not be able to fulfill the community’s current demand of 0.24 mgd with 90% confidence, the drought vulnerability of the system is classified as AT-RISK.

Additional Notes

Note that Carthage purchases between 0.02 and 0.07 mgd per year from Hamilton to supplement its own water supply based on water use reported between 2005 and 2008.