Spatial impact of organic matters from point sources on stream water quality

Evaluation of the performance of multiple water quality loading index systems for Sapgyo River

“…The generated pollutants have been computed to evaluate the water quality scales or water quality indices (WQls) of the point sources and non-point sources which are generating the pollutants. The BOD concentration to be measured at downstream from the WTPs can be simulated by the following equation (Liu and Chen, 2009):…”

Handling Water through Irrigation Watershed Management for Coping with Stream Pollution Dilution in Phetchaburi River, Thailand

“…It is remarkable for careful observation when flow velocity increased up to 377 m 3 /s that trends of BOD and DO looked the same downslope due to much more rainwater of heavy rainstorm is usually plenty of DO and also increasing BOD in stream water. For this reason, the decrease of DO because it was used for bacterial organic digestion process that made BOD lowering as well but interesting point was on the city zone in terms of urban rainwater in city zone being composed of DO while drastic increases of BOD was occurred by erosion process due to much more excessive rainwater on the ground surface with very less infiltration rate (Cazelles et al, 1991;Loomis et al, 2000;Burnett et al, 2007;Chen et al, 2008;Liu et al, 2009;Chu et al, 2010;LERD, 2012;Mangimbulude et al, 2012;Rakthai, 2012;Kraus et al, 2014).…”

“…The key points on irrigation watershed management is to handle water yields in stream for maintaining optimum quantity, quality, and flow regime in order to ready-use for irrigating, self purifying, and aquatic animal and plant ecology in wet and dry seasons without lacking the desirable quality water flow (Chunkao, 1981;Liu et al 2009;Kraus et al, 2014). Unluckily, most of rivers in the whole country has been changed the forested cover in headwater to become the cultivated and human settlement areas that causing the streams running dry in summer but high amount of excess water in wet season and turning to be flooded on flatlands as pointed out by Wang et al (1978); Chunkao et al (1981); Vagnetti et al (2003); Burnet et al (2007); Chunkao et al (2008); Liu and Chen (2009) ;Wahla et al (2008); Chu et al (2010); PCD (2010); Chunkao et al (2012); PCD (2013). For solving such problem, the storage dam construction could be the best tool for restoring the excess water of wet flow for distributing it in dry period to serve needs of all end users without happening water shortage.…”

Appropriate Discharge from Diversion Dam to Dilute High Concentrated Community Wastewater of Riverbank Settlements along Phetchaburi River in Phetchaburi Province, Thailand

“…It is noticed that the concentration of contaminants in stream pollution was varied among seasons and amount of streamflow as well as the diluting-rainwater capability (LERD, 2011;LERD, 2012;Thaipichitburapa et al, 2010;Streeter & Pheiplps, 1958;Reynolds & Edwards, 1995;Berkun, 2005;Robison & Maris, 1985;Faerge et al, 2001). In addition, the stream length was influenced in the excessive contaminants owning to the efficiency of self purification in which the longer the distance is the more the recovery (Ntengwe, 2006;Vagnetti et al, 2003;Cazelles et al, 1991;Tanji et al, 2006;McColl, 1974;Liu & Chen, 2009;Kraus et al, 2014). In the same situation, if the bacterial digesting rate is less than organic wastes (both solid and liquid) releasing rate then the stream pollution may be caused the seriousness, especially the zones of dense populated in the riverine systems (Derx et al, 2014;Pattamapitoon, 2013;Vargaftik et al, 1983;Wang et al, 1978;Tyagi et al, 1999;Penha-Lopes et al, 2011;Srigate, 2009;Streeter & Phelps, 1958).…”

“…Long term experiences can be brought up to initiate the dilution process for deducting higher toxic concentrations of urban effluent down to natural stream-water flowing in which the diluted water should contain non-toxic amount of contaminants (Luderitz et al, 2004;Kraus et al, 2014;Liu & Chen, 2009;Faulkner et al, 2000). Luckily, Phetchaburi watershed has been composed of Kang Krachan storage dam and Phetchaburi diversion dam for providing mainly to large irrigated areas for growing rice, fruit trees, farm plants, livestocks, and waterworks (Linsley et al, 1988;Lajoie et al, 2007;Matthews & Richter, 2007;Chunkao et al, 1981;Coleman, 1953;Cheng et al, 2002;Berkowitz et al, 2011;Brooks et al, 1991;Brooks et al, 2013;LERD, 2011;Vorawong et al, 2014, Poommai et al, 2013.…”