英文摘要 |
I. River Quality Monitoring
Based on water quality monitoring results of trunk sewer in Chiayi city, pollution sources in five monitoring points at Bajhang River including Riverside Park (influent and effluent water), earth ditch by Hsiapei Section No. 49, drainage ditch under Chunghsiao Bridge and Tslai drainage way, etc. are mainly biochemical oxygen demand (BOD) and ammonia nitrogen (NH3-N). Based on location analysis, pollution in Tslai drainage way is the most severe, mainly from sanitary sewage discharge; severe stream segments mostly presented in five monitoring points at Putze River, including Northern Main Drainage, Central Main Drainage, Western Main Drainage and Dingchang Community (influent and effluent water), etc.
Based on the river monitoring in Bajhang River, severe pollution test items for monthly monitoring points at Yungchin No.1 Bridge and Taochiangjun mainly are suspended solid (SS) and BOD, in which dissolved oxygen always maintains middle level pollution; in flood season from May to September, SS concentration may maintain middle to severe pollution, causing that the influence of SS on RPI in these two observation stations is greater than other test items.
Based on the river monitoring in Putze River, monthly monitoring points are at Lushan Bridge and Huahsing Bridge, the main pollutants in these stream segments of which are SS, NH3-N and BOD are influenced by sanitary sewage of branch drainage in Chiayi City, causing middle to severe pollution presented in the stream segment.
II. Total Maximum Daily Loads (TMDLs)
Establish water quality simulation model for BOD and NH3-N in Niuchou River (Sungchu Bridge Station – Yuehmeitan Bridge); that is the pollution source entering into Niuchou River from Minhsiung drainage and Chiayi’s Northern Main Drainage, mainly sanitary sewage and little industrial wastewater, causing that BOD may rise to middle pollution and up, and NH3-N to severe pollution.
According to general water quality item in each observation station at Niuchou River drainage basin in recent 5 years, achieving rate analysis result and background information survey result for water quality standard show that the main population resource in Niuchou River Bridge is sanitary sewage with only 3.3% minimum achieving rate for NH3-N and 58.3% for BOD. Therefore, the observation station selected to preferentially control the damage is for BOD item at Niuchou River Bridge.
After simulation analysis, the pipes of public sewer will be connected in 2031. BOD item at Niuchou River Bridge then can achieve C-class water body quality standard, and NH3-N item must achieve more than 95% reduction rate before achieving C-class water body requirement.
The length of sewage pipe network system will be laid is about 95,987 meter in the whole period in Chiayi City, and user pipe connection rate will be increased more than 80% after the completion. Where reduction rate for each pollutant achieves more than 80%, BOD can be improved to near water body classification and water quality standard, and NH3-N still has room to be improved. Consequently, construction of public sewer can effectively increase achieving rate for water body classification and water quality standard. It’s proposed to execute the following items before the pipe connection of sewage system has not yet been completed:
1.Continue to check normal operation for sewage treatment equipment in controlled community in tutoring region.
2.Control hypermarkets, restaurants, hotels and newly-built community residences, adding 7 units (including 2 hypermarkets) in 2015 and further controlling BOD and NH3-N pollutants discharge.
3.Strengthen the audit of controlled business classification, aiming at pollution load area to check water discharge with water quality instrument for 24-hour tracking per unit each month.
4.Regularly clean septic tank to expand administrative objects for not only continually promoting disposal of septic tanks in government agencies and schools, but also listing those administrations over a certain scales as promotional objects, and increase regular cleaning rate for septic tank.
III. Guidance to Promote River Patrol Team
Investigate river patrol team every month for opinion exchange. So far, four sessions of education training and connection assembly had been held in this year to enhance professional knowledge for patrol team, and Teacher Hung, Ching-Yi, Sun, Yi-Min and Wu, Su-Mei of Chang Jung Christian University were invited to give lectures for the contents, including environmental education combined with water environment protection, expecting team members to understand that daily patrol is an important subject in environmental education through the issues, and deepen team members to protect living surrounding environment and develop hometown-loving spirit; hold one session of river patrol team’s visiting tour in other cities and award ceremony for outstanding patrol team, and conduct opinion exchange with Taichung Patrol Team to learn local characteristic culture through this activity.
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