STUDY ON APPLYING THE TMDLs METHOD TO CALCULATE THE TOTAL MAXIMUM DAILY LOAD OF POLLUTION COMPONENTS N, P, BOD FOR RIVER SEGMENTS WITH DIFFERENT WATER USE PURPOSE
Abstract
Determining total maximum daily loads (TMDL) for river segments is important for river water quality control and management based on total pollutant load aproach. This aproach has been applied suscessfully in many advanced countries, such as USA, Canada, Japan, Korea,… This article presents the results of calculation of the total maximum daily load for N, P for Cau river segments in Thai Nguyen province with different water use purposes. The SWAT model and QUAL2K model have been established, calibrated and validated for Cau river basin against monitoring data in 2004-2019 period. Using these models, the TMDLs of N, P, BOD are calculated for flow regimes: low flow. The TMDL of NH4 is 19.1 ton/day, PO4 is 3.6 ton/day and BOD is 93.1 ton/day respectively. Based on the calculation results, some solutions for improving the Cau River water environment have been proposed.