Technical Bulletin No. 0457: Modifications to the QUAL-2 Water Quality Model and User Manual for QUAL-2E Version 2.2

Bulletin No. 437 provided a synopsis of these changes and a user manual to assist industry personnel and others with its use. As a result of the increasing number of applications, the computer code was changed to reflect differing model assumptions. For these reasons, Technical Bulletin No. 437 was revised and amended to reflect additions and clarifications.