For the sake of its continuous active promotion of river pollution control, a suitable optimal site of 「Planning and Detail Design for In-Situ Control and its Tributary Drainage Survey of Hsin Hu Wei Chi (HHWC) in 2009」 (abbreviated as this project) is to be chosen by Environmental Protection Bureau (EPB), Yun Lin County Government (YLCG), for water quality improvement via in-situ control. It’s expected to meet the prospect of everlasting development that the new milestone of no anaerobe & odor and activation for embankment & slope protection in HHWC is available in the future; the residents’ best site of leisure, sightseeing, education and natural experience is also provided by means of the completion of this project. This project scope is located in HHWC, between Cho Shui Chi (CSC) and Old Hu Wei Chi (OHWC) and belonging to the regional river under YLCG control; main pollution sources include pasturage, industry, sanitary sewage and littoral waste. According to the contract contents, items of execution work include: 1. References and cases survey and collection of pollution site control, reduction and management of domestic and foreign rivers. 2. Survey and assessment at least 2 sites suitable for installation of natural purification system in HHWC basin; also study & selection of feasible cases and benefit assessment. 3. Completion of planning, design and supervising construction for natural purification system in HHWC basin. 4. Technical advising meeting of expert scholar or relevant units at least once. 5. Adaptation of manual for operation and maintenance after engineering completion. 6. Completion of necessary guidance meeting at least once in the preliminarily planning, explaining this planning idea to the audience and also listening to their prospects used for planning reference. 7. Completion of survey and analysis for selection and planning of 1 site of the in-situ control in the HHWC basin. 8. Production of 1,000 guidance lists for river pollution control. 9. Suitable guidance manual and wall chart of school student and teacher or community resident via understandable edition and amendment, in connection with native features and also in match with cartoon, illustration or in-situ phototaking. The option of installation site after comprehensive assessment in every relevant factor, 2 decided sites for optimal planning are wetland with 2.0 hectares area or so (culture & education land use) away from 300 meters in the south bank of downstream of Chung Cheng Bridge (CCB) of HHWC and Ma Kuang Farm (MKF) with approximate 4.0 hectares land area in the 1st phase away from 220 meters or so in the south bank of Hsin Chuang Zi Main Drainage (HCZMD) , around the 19th Taiwan Provincial Highway, separately. At the site of HCZMD, MKF, its drainage is about 12,441 CMD (during dry period), approximate 3,211 and 8,302 kg/yr BOD and SS, individually are annually decreasable. At the wetland site in the CCB downstream of HHWC, its base flow discharge is about 38,016～270,240 CMD (during dry period), 1,082 & 60,378 and 6,684 and 11,366 kg/yr or so BOD and SS are yearly reducible in short term and midterm & long term , respectively.