Finding of No Significant Impact for the Environmental Assessment for the Strategic Petroleum Reserve West Hackberry Facility Raw Water Intake Pipeline Replacement Cameron and Calcasieu Parishes, Louisiana

Microbial contamination of surface waters constitutes a health risk for drinking water consumers which may be lowered by closing the raw water intake. We have evaluated microbial discharge events reported in the river Göta älv, which is used for raw water supply to the city of Göteborg. Elevated levels of faecal indicator bacteria were observed during periods of closed raw water intake. High bacteria levels were, however, also occasionally detected during periods of open intake, probably as a result of microbial discharge far upstream in the river which may be difficult to predict and manage by closing the intake. Accumulated upstream precipitations, resulting in surface runoff and wastewater contaminations in the catchment, correlated positively with the levels of total coliforms, E. coli, intestinal enterococci and sulfite-reducing clostridia. Levels of faecal indicator organisms were negatively correlated to the water temperature due to enhanced survival at lower temperatures. Wastewater discharges from a municipality located just upstream of the water intake resulted in elevated E. coli concentrations downstream at the raw water intake for Göteborg. To improve the prediction of microbial contaminations within the river Göta älv, monitoring data on turbidity and upstream precipitation are of particular importance.

Download Full-text

Shoal creek raw water intake and pump station construction on Lake Lanier

North American Tunneling 2004 ◽

10.1201/9781439833759.ch69 ◽

2004 ◽

Author(s):

D Ackerman ◽

R Wiek ◽

R Gutridge

Keyword(s):

Water Intake ◽

Raw Water ◽

Pump Station

Download Full-text

Environmental Assessment on the leasing of the Strategic Petroleum Reserve, St. James Terminal, St. James Parish, Louisiana

10.2172/208345 ◽

1995 ◽

Author(s):

Keyword(s):

Environmental Assessment ◽

Strategic Petroleum Reserve

Download Full-text

The implications of point source phosphorus management to potable water treatment

Water Science & Technology ◽

10.2166/wst.1998.0158 ◽

1998 ◽

Vol 37 (2) ◽

pp. 343-350

Author(s):

Ralph G. Heath ◽

Machiel C. Steynberg ◽

Rita Guglielmi ◽

Annelie L. Maritz

Keyword(s):

Waste Water ◽

Water Treatment ◽

South African ◽

Water Intake ◽

Waste Treatment ◽

Waste Water Treatment ◽

Algal Species ◽

Raw Water ◽

Urban Settlements ◽

Informal Urban Settlements

The Vaal River Barrage reservoir is an important source of raw water for Rand Water which supplies at least 10 million people with drinking water daily. Return effluents from waste water treatment works, industries and informal urban settlements in the catchment has resulted in algal problems in the raw water and treatment process. In order to attempt to reduce the effect of eutrophication of South African inland water quality the Department of Water Affairs implemented in 1985 a 1 mg/l ortho-phosphate standard for waste water treatment works effluents. The amount of phosphate originating from the waste treatment works decreased significantly over the 10 years after the standard was implemented even though 40% of the time the works do not comply to the standard. This has resulted in no significant change in the chlorophyll values at Rand Water Intake No. 1. The algal species composition has changed with blue-greens becoming more dominant which has resulted in a higher incidence of algal related problems. The stabilizing of the chlorophyll values is not only as a result of lower ortho-phosphate levels but also due to residence times, turbidity and conductivity. To further reduce the algal concentrations at Rand Water Intake No. 1 the 1 mg/l ortho-phosphate standard will have to be enforced, the standard possibly reduced and diffuse sources managed on a catchment basis.

Download Full-text

An approach for determining the most critical among a suite of chemical contaminants at a drinking water intake

Water Science & Technology Water Supply ◽

10.2166/ws.2013.075 ◽

2013 ◽

Vol 13 (3) ◽

pp. 835-845

Author(s):

Fei Chen ◽

William B. Anderson ◽

Peter M. Huck

Keyword(s):

Water Quality ◽

Drinking Water ◽

Water Intake ◽

Treatment Plant ◽

Quality Data ◽

Exceedance Probability ◽

Raw Water ◽

Water Quality Data ◽

Treatment Processes ◽

Raw Water Quality

An integrated approach for the identification and assessment of the most critical chemical contaminant(s) at a drinking water intake has been developed. It involves the determination of a threshold or critical raw water concentration (CRWC) for target contaminants using the observed overall removal efficiency of a specific water treatment plant (WTP) and regulated drinking water concentrations for the target contaminants. The exceedance probability relative to the CRWC based on historical raw water quality monitoring data is then calculated. Finally, the integration of the raw water quality data and the overall efficiency of a particular WTP sequence allows for identification of the most critical contaminant(s) as well as an advance indication of which contaminants are most likely to challenge a plant. The proactive nature of this approach gives a utility the impetus and time to assess current treatment processes and potential alternatives. In addition, it was found that three- or four-parameter theoretical distributions are more appropriate than two-parameter probability distributions for the fitting of raw water quality data. This study reveals that the reliance on raw and/or treated water contaminant concentrations in isolation or on theoretical removals through treatment processes can, in some circumstances, be misguided.

Download Full-text

Analisis Pasang Surut di Perairan Sungai Musi Menggunakan Metode Least Square (Studi Kasus Intake Air Baku Sistem Gandus Kota Palembang)

CANTILEVER ◽

10.35139/cantilever.v9i2.57 ◽

2021 ◽

Vol 9 (2) ◽

pp. 115-124

Author(s):

Agus Saputra ◽

Taufik Ari Gunawan ◽

Imroatul Chalimah Juliana

Keyword(s):

Water Level ◽

River Water ◽

Water Intake ◽

Least Square Method ◽

Least Square ◽

Primary Data ◽

Raw Water ◽

Pump Operation ◽

Safe Level ◽

Musi River

The tides, which affect the water level of the Musi River causes some problems to occur in Palembang City. One of the main problems related to the tides of the Musi River, especially the low tide, is the failure of the raw water intake building of Regional Drinking Water Company (PDAM) Tirta Musi, Palembang City to operate. At a certain time the river water level recedes, the minimum water level entering the intake pump room is lower than the safe level for the pump to run. In this study, an analysis of the tides of the Musi River was carried out using the Least Square method to evaluate the design of the raw water intake building for the Gandus system to disclose whether it meets the minimum elevation requirements for pump operation. The field observations of the tides were carried out for 15 days for every 1 hour to obtain the primary data for this study using the Hobo Water Meter. The results of this study indicate that the type of the tides in the location of the study is a mixed tidal type with a Formzahl Value of 2.01. 4. Against the design plan of the gandus system of raw water intake, there is a chance that the elevation of the river water level is at 0.5 m from the end of the pump suction pipe, in which the pump cannot function.

Download Full-text

A comparative assessment of selected raw water intake systems in Rwanda

Water Practice & Technology ◽

10.2166/wpt.2012.045 ◽

2012 ◽

Vol 7 (2) ◽

Author(s):

I. Nhapi ◽

A. J. Nshimiyimana ◽

U. G. Wali ◽

F. O. K. Anyemedu ◽

J. J. Kashaigili

Keyword(s):

Water Supply ◽

Water Intake ◽

Rural Areas ◽

Urban Areas ◽

Water Levels ◽

Bank Filtration ◽

Raw Water ◽

Groundwater Abstraction ◽

Water Turbidity ◽

Physical Measurements

After the genocide of 1994, Rwanda has been struggling to contain urban migration and its pressures on existing facilities. Water supply coverage is low at 76% in urban areas and 68% in rural areas. This implies that huge investments are required to meet the Millennium Development Goals on water supply and sanitation. This study was conducted to assess the existing problems of raw water intake systems at Yanze and Nyabarongo intakes in Kigali; Shyogwe intake in Ruhango District; and Kadahokwa intake in Huye District. The study was in response to high amounts of sediments in raw water which literally clogged the intake systems for a number of days, resulting in erratic water supplies to the residents in the rainy season. The study focused on performance problems of the intake systems, raw water turbidity variations and the assessment of how environmental concerns could be addressed in the design of intake systems in areas of high soil erosion activities. Data was collected through interviews and physical measurements. The study revealed that flooding, intake site selection, erosion, screen clogging, intake protection, high raw water turbidity, inadequacy of raw water supplied to the water treatment plants, and low downstream environmental flows were the main intake problems. The Yanze intake had worst problems with high levels of flooding, erosion, sedimentation, and high raw water turbidity levels. The bank filtration system at Nyabarongo gave the least problems of raw water turbidity. Yanze and Nyabugogo river intakes systems were found to be threatened by decreasing water levels attributed to surrounding upstream landuse activities. It was recommended that proper maintenance of existing structures, landuse management around river intakes, use of well-designed reservoir abstraction systems, increased groundwater abstraction systems (including bank filtration), would greatly improve the performance of intake systems in Rwanda.

Download Full-text