Introduction Piano Key weirs (PKWs) are a hydraulically attractive alternative to linear overflow weirs, increasing the unit discharge at the unregulated spillway inlet for similar heads and spillway widths. This advantage, allowing for operation of dam reservoirs on elevated supply levels thus providing an increased retention volume, is a result of the non-linear nature of PKWs being folded ba...

The ‘range of variability approach’ (RVA) and mapping technique are used to investigate the spatial variability of hydrologic alterations (HA) due to dam construction along the middle and lower Yellow River, China, over the past five decades. The impacts of climate variability on hydrological process have been removed during wet and dry periods and the focus is on the impacts of human activitie...

Hydroelectric reservoirs bury significant amounts of organic carbon (OC) in their sediments. Many reservoirs are characterized by high sedimentation rates, low oxygen concentrations in bottom water and a high share of terrestrially derived OC, and all of these factors have been linked to a high efficiency of OC burial. However, investigations of OC burial efficiency (OCBE, i.e., the ratio betwe...

over a period of three months (summer), 108 samples of water collected from four hospitals in te-hran. they were taken from numerous potable and non-potable water, including main supply cis-terns, calorifiers, hot and cold tap water, shower, cooling tower and drain of air condition system. culturing of concentrated and non-concentrated water samples on buffered charcoal yeast extract (bcye) aga...

The present paper has determined the radioactivity concentrations, which are due to natural occurrence of radionuclides along with heavy metal concentration in water, sediment, and fish from 2 reservoirs in Ghana. Heavy metal concentrations in all samples were generally within the WHO safe limits with the average activity concentrations of 238U, 232Th, and 40K in water being respectively 0.42±0...

farmers in the indus basin, pakistan have generally switched to groundwater for additional water supplies due to the irregular supply of irrigation water; currently over 50% of the agricultural land in the basin is at least partially irrigated by tube-wells. these wells pump fresh groundwater, which essentially is the result of massive leakage from irrigation canals into the originally saltwate...

Farmers in the Indus Basin, Pakistan have generally switched to groundwater for additional water supplies due to the irregular supply of irrigation water; currently over 50% of the agricultural land in the basin is at least partially irrigated by tubewells. These wells pump fresh groundwater, which essentially is the result of massive leakage from irrigation canals into the originally saltwater...

Jordan is considered one of the countries in the world with the scarcest of water resources. This has led to deterioration of the groundwater quality and an increase in the salinity levels. The dominant environmental challenge expanding population. Rainfall is confined largely to the winter season and ranges from around 660 mm in the north-west of the country to less than 130 mm in the extreme ...

Recently the design flows of many dams have been re-evaluated, resulting in spills often larger than the original ones. In many cases, occurrence of revised flows would result in dam overtopping because of insufficient storage and spillway capacity of reservoirs. Embankment dams whilst common are more likely to fail than other dam types when overtopped in an uncontrolled manner because of breac...

the present paper has determined the radioactivity concentrations, which are due to natural occurrence of radionuclides along with heavy metal concentration in water, sediment, and fish from 2 reservoirs in ghana. heavy metal concentrations in all samples were generally within the who safe limits with the average activity concentrations of 238u, 232th, and 40k in water being respectively 0.42±0...