Assessing the load capacity of the Pho Day river in the sections flowing through Tuyen Quang and Vinh Phuc provinces and proposing solutions for the sustainable use of water resources
Abstract
Assessing the load capacity of a river and then devising a plan to allocate flow to different types of discharge in the river basin is a work of practical significance to protect the water quality of that river. This study calculates and evaluates the receiving capacity and environmental carrying capacity in two sections of the river Pho Day 1 - flowing through Tuyen Quang province and Pho Day 2 - flowing through Vinh Phuc province. Research results show that, in the period 2022 - 2025, both river sections can still receive wastewater for the parameters TN, NH4+, BOD5, and COD but no longer have the ability to receive wastewater for 2 parameters TP and TSS. In 2026 - 2030, calculations show that receiving wastewater with all six water quality parameters is no longer possible. The cause of the deterioration of river water quality leads to the possibility of losing the river's carrying capacity. Every day, the river must receive about 11.758 m3 of wastewater from industrial wastewater (12 %), domestic wastewater (55 %), livestock wastewater (30 %), and medical sewage (3 %). The water quality parameters in these wastewater samples are all higher than the allowed standards. To increase the river's carrying capacity, first of all, it is necessary to control wastewater sources strictly, ensuring wastewater treatment at the source meets allowed standards before discharging into receiving sources. In addition, a detailed plan to appropriately allocate water use for different types of economies in the basin is also a problem that needs to be considered thoroughly.
