Jiaozhou Bay Water Environmental Quality Assessment And Pollution Control

Jiaozhou Bay is a typical semi-enclosed bay link to the Yellow Sea, which is important to economic and social development of Qingdao. In recent years, by the influence of inputs of runoff, agricultural and industrial wastewater, DIN content far exceeded in the estuary, eutrophication degree of local water is higher, number of red tide increases, which bring serious damage to economic and health. This research is precisely analyzing the long-term changes of water factors and pollutions, evaluating the quality of sea environment, and proposing pollution control measures.The distribution of water factors analysis. From 2008 to 2009, the contents of DO,pH,COD,Oil,Cu,Zn,As,Cr,Hg,Cd and Pb meet grade I water standard. The content of DIN meets gradeⅣ, the content of PO4-P meet gradeⅡ-Ⅲ. The spatial distribution of pollutions appeared a downward trend from eastern estuary and northern breeding area to low concentration areas including bay center and the mouth. From 1996 to 2009, Content of DIN meet gradeⅢ, annual change shows trends of increased and then decreased. Content of PO4-P meet gradeⅡ.Jiaozhou Bay water quality assessment. From 2008 to 2009,Single-factor evaluation show primary pollutant is DIN, followed by the PO4-P,Area evaluation show water area of gradeⅣbelow is 55.8% and 35.3%, water quality changes better from north to south, Licun estuary, Loushan estuary and Hongdao breeding show gradeⅣ, water quality evaluation is worse. Potential eutrophication assessment shows that Jiaozhou Bay is in Phosphorus-limit potential eutrophication,estuaries show serious eutrophication, Assessment of organic pollution index shows that organic pollution is in gradeⅡ,water is starting polluted, organic pollution of estuaries is serious. From 1996 to 2009, Jiaozhou Bay Water Quality Evaluation is poor, and during "fifth" shows very poor water quality, water quality worse than gradeⅣis more than 40%.Main pollutants of Jiaozhou Bay analysis. Sewage units are divided into eight units including Tuandao, Haibo River, Banqiaofang River, Loushan River, Moshui River, Dagu River and Qianwan. Input of main pollutants shows quantity of COD is maximum,NH4-N second, and the third one is TP. Input of COD is 52879 ton every year, life sewage is the main source account 49.7%, Loushan River, Licun River, Dagu River have the highest contribution rate; Input of NH4-N is 7411 ton every year, Life sewage account 52.6%, Haibo River,Licun River,Dagu River have the highest contribution rate; ;Input of Totle P is 740 ton every year, life sewage account 50.3%, Haibo River, Licun River, Dagu River have the highest contribution rate.Pollution control of Jiaozhou Bay water including increase of infrastructure, establishment of broad coverage of sewage collection pipe network, sewage treatment plants to promote new construction, renovation and expansion project; Adjustment the industrial structure and industrial distribution, adjustment the structural industrial pollution, strict enforcement of total control, and promote cleaner Production; strong point source pollution control; recycling of reclaimed water; promote ecological restoration.