Archives

  • Archives
  • >
  • Home

DOI : ,    Vol.4, No.4, 11 ~ 27, 1996
Title
Predicting on Water Quality and Water Treatment Measures for the Nakdong River
강용태Yong Tae Kang,양희천Hee Cheon Yang
Abstract
The Nakdong river being used as drinking water sources for Pusan metropolitan city has contaminated due to inflow of inadequately treated wastewater from the tributaries into the river. In order to predict the characteristics of the river according to the variations of the flow and contaminants loading, water quality of the Nakdong river for a year was simulated by QUAL2E. The intensive surveys for the characteristics of the river section from Dalsung to Mulgum the downstream end of the Nakdong river were conducted during December 1995 to November 1996. The results of this study were summarized as follows. 1. In the lower reaches of the Nakdong river under Hanam the velocity of flow was quite slow like a lake. In case of COD the levels in Mulgum was from 7.0㎎/ℓ to 11.2㎎/ℓ and these values turned out to be fifth grade in the water quality criteria of the lake water. 2. The Nakdong river is a river in which the coefficient of riverbed that is presented as the ratio of maximum flow to minimum flow is too large. During the period of investigation the maximum value for the instance of a branch stream was 1:487.3 in the point of Milryang river and for a main stream, 1:124.6 in the point of Samryangjin. Therefore, the phenomenon of water shortage was too heavy in a period of dry season. 3. In order to improve the quality of the river the Master Plan of the all area of the river basin needs over all. 4. T-N, T-P levels ranged from 4.123㎎/ℓ to 25.361㎎/ℓ and from 0.475㎎/ℓ to 2.458㎎/ℓ, respectively, in the middle and upper part of Nakdong river and due to these effects Chlorophyll-a in Mulgum area that is clean water resource of Pusan metropolitan city was very significant and ranged from 57.1㎎/㎥ to 209.5㎎/㎥. Accordingly the results have it that existing wastewater, livestock wastewater and urgently industrial wastewater treatment systems should be converted to advanced wastewater treatment system or wastewater reuse system. 5. In a wide water supply scheme of abstrating on the lower of Hapchun Dam, the usual abstraction of 100 million ㎥/day aggravates the water quality of Mulgum that is the water resource of Pusan metropolitan city. Therefore, in order to settle these problems, the optimum operating method after hanging Hapchun Dam into water supply exclusive dam should be examined so that water quality improvement could be achieved by supplying water for river maintenance. 6. It could be realized that the creation of Wichun industrial complex would make much worse the water quality in Mulgum in the value of BOD: 0.2㎎/ℓ, COD: 0.3㎎/ℓ. And also it will not be feasibable to introduce a perfect non-discharge system of industrial wastewater in current domestic situations because the development of water treatment technology for 100 percent of treated effluent reuse and the rise of cost of production were not under consideration. 7. It is very urgent as a short term counter measure to introduce pretreatment facility by way of Aerated Biofilm filtration for the water quality improvement of clean raw water of Pusan metropolitan city because a long period is needed to regenerates all the water of river. 8. Non-point sources in the area of the Nakdong river and contaminated sludge layer on riverbed should be analyized as soon as possible, and then the counter plan for the treatment removal scheme, which is included in the content of general Master Plan, also should be settle by the prior orders.
Key Words
pdf view PDF