Author(s): Zhuohang Xin; Tsuyoshi Kinouchi; Tomoyuki Nakaya
Linked Author(s):
Keywords: Stream temperature; 1D dynamic model; Field measurement; Heat budget; Surface-subsurface water interaction
Abstract: To reveal factors relevant in controlling stream temperatures in summer and winter seasons of the Tama River, field measurement, water and heat budget analysis as well as model development were performed in this study. Detailed information on water temperature, flow rate, meteorological variables as well as water-sediment heat flux was obtained through the intensive field measurements. Water and heat budgets analysis indicated that the wastewater was the prior factor contributing to water and heat gains in middle and downstream reaches. The temperatures at middle stream sites were mitigated by wastewater effluents in summer while increased by wastewater in winter. A 1-D dynamic model for river flow and heat transport was developed, taking the effect of surface-subsurface water interaction and wastewater effluents into accounts. We concluded that the current stream temperature regime in the Tama River downstream reaches is maintained by the heat dispersion in the riverbed sediment and also the effluents of treated wastewater.
Year: 2013