Application of QUAL2K for Water Quality Modeling and Reduction Strategies of the Major Pollution Reaches in the De-Zi-Kuo River

• Main Authors: Wu,Pei-chien, 吳佩倩
• Other Authors: Hann-Chyuan Chiang
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/19198281510253859236

碩士 === 國立宜蘭大學 === 綠色科技學程碩士在職專班 === 101 === Yilan County have major rivers such as Lanyang river, Shincheng river, Su-ao river, Nanao river, De-zi-kuo river and other rivers. According to EPA “National Environmental Water Quality Information” as quoted by the five major rivers on Yilan County, the monitoring results over the years are good. However, in recent years, the monitoring results at Cijie Bridge station of the De-zi-kuo river show that the water quality class often reaches moderate to severe pollution. The main pollution item is ammonia nitrogen, followed by suspended solids and biochemical oxygen demand. In this study, the major pollution reaches in the De-zi-kuo river from source to Cijie Bridge station was discussed. We use QUAL2K for water quality modeling and develop reduction strategies in order to understand the changes of water quality. The results may be as a reference for pollution remediation and improvement in the major reaches in the De-zi-kuo river. Conclusions of this study are summarized as follows: (1) to estimate the amount of pollution, the main source of pollution in the major pollution reaches in the De-zi-kuo river are livestock wastewater and domestic sewage. (2) QUAL2K simulation results indicated that the MAPE of the simulated and monitored values from 11.5 to 29.3%, simulation capability is good to reasonable projections, so the display mode simulation results have credibility. (3)The strategy of the promoting sewage treatment rate can reduce domestic sewage discharge into the De-zi-kuo river. The result lead to reach water quality improvement goals. (4) livestock waste to Sanmin constructed wetland system, promote clean pig raising, strengthening the reduction of inspection on upstream pollution sources of Cijie Bridge are control strategies.Comparing the simulation results of the above strategies, the Sanmin constructed wetland system and promote clean pig raising can significantly reduce the pollution of livestock wastewater on Cijie Bridge station. Based on the above results, it is suggested that the control of pollution by domestic sewage should be a priority remediation method. Next, the functional improvement and regular audits are useful for handling facilities on existing Sanmin constructed wetland system .Additionally, continue to promote clean pig raising, strengthen inspection and control of pollution sources on upstream of Cijie Bridge can improve water quality of the major pollution reaches in the De-zi-kuo river.