ABSTRACT: Indiscriminate cutting of hills in the Sylhet region has become a major environmental issue. The nature and life style of Sylhet intimately related with the hills are thus under the threat of a drastic imbalance in its ecosystem. Due to such hill cutting the mostly affected sectors of this region will be its weather and climate, geomorphology and hydrology, and the indigenous flora and ...
In Israel, the long, dry summer is followed by a short rainy winter season causing high-flow, high-velocity streams and flooding often occurs. Serving as the divider for the north and south lanes of the Tel-Aviv Freeway, the Ayalon channel was designed to handle the surging waters of the Ayalon River during Tel-Aviv’s winter rainy season. Since the channel's original design, the city has ...
Combined processes of land-surface hydrology and hydroclimatology influence the response of a watershed to different hydroclimatic variables. In this paper, streamflow response of a watershed to hydrometeorological variables is investigated over a part of two tropical Indian rivers – Narmada and Mahanadi. The proposed HydroClimatic Conceptual Streamflow (HCCS) model is able to consider ...
The role of biodegradation in the attenuation of natural organic matter (NOM) was investigated in long-term experiments that simulate artificial ground water recharge (AGR) for drinking water production. Lake water containing 5.8 mg L–1 total organic carbon (TOC) was continuously fed into an 18.5-m-long sand column. During the 941 d of operation, on average 76 and 81% of TOC was removed within ...
Received for publication May 4, 2008. Denitrification hotspots in riparian aquifers often develop in a relatively narrow zone at the upland–riparian interface, where nitrate-rich ground water of upland origin interacts with available soil organic carbon. In riparian paddy fields, denitrification in the aquifer has received less attention than that in the surface water and soil. This study aimed ...
The Musi basin is a sub-basin of the river Krishna in India. Data on ground water levels for 20 years (1985?2004) including the data of Digital Water Level Recorders (DWLR) is analysed to investigate the large scale ground water withdrawal and its affects on reducing the inflows reaching the downstream reservoirs in the basin. The investigations have revealed that the deeper the pre-monsoon ...
This document describes how to properly install the Rainstore3 water storage system with geotextile fabric for stormwater drainage detention and retention. Detention allows for short-term storage and release of storm water through outlet pipes. Nearby water treatment plants may have a limited capacity for handling storm water and thus, stormwater needs to be temporarily detained on site. ...
Pacific Environmental Resources Corp. (PERC) is a water quality service provider offering clients a total solution in partnership with nature and the surrounding environment. PERC is a leading design / build / operate company in the wastewater industry. PERC’s total solution provides a scalable and modular design delivered under a single contractual agreement. Clients enjoy the benefits of ...
An aerial comparison of a multiple lake system, that reveals how groundwater recharge occurs in the basalt geology of the Columbia Basin in just two years time Continue reading the full ...
Strength of Grasspave2 Paving: Grasspave2 paving offers a high level of rigidity and load bearing capacity, consistent with hard surfaced materials, such as asphalt and concrete -- equal or greater than 5000 psi when filled with sand (seeded or sodded). Environmental Advantages of Grasspave2 Paving: (compared to Asphalt & Concrete): Lower stormwater runoff. High percolation rates. ...
Groundwater is vulnerable to overdraft and depletion, especially in relatively dry regions where natural recharge rates are very low and groundwater is the main source of water. Artificial recharge of groundwater with treated wastewater has been widely adopted as a technique to replenish the overdraft aquifers. Indeed, in the USA, the technique has been practised for a long time. In 1981, a ...
Selection between ground and surface water in community water supply has been one of the key strategic questions in Finland since the early 1900s. After some cities failed to find reliable groundwater sources, many turned to surface waters. Since the 1950s the use of groundwater and artificial recharged groundwater have continuously increased. Presently their use is promoted by the government and ...
In this article, a novel approach to measuring the gross groundwater recharge rate over a district area is presented. It is based on soil resistivity measurements. It is nondestructive, and allows quick, low-cost mapping of infiltration over large areas, which makes it particularly relevant for land planning. An empirical relationship between soil resistivity, ρ, and permeability, k, must be ...
Global Diving & Salvage, Inc. was contracted by the Alameda County Water District to install and maintain emergency pumps as a work around after a culvert collapse in the Quarry Lakes in Freemont, CA. The lakes were originally gravel quarries’ whose yield was used during the building of western portion of the Intercontinental Railroad. After quarrying activities came to an end, the ...
The urban water balance can be attenuated to the natural by water-permeable pavements (WPPs). Furthermore, WPPs have a 16% higher evaporation rate than impermeable pavements, which can lead to a better urban climate. Evaporation rates from pavements are influenced by the pavement surface and by the deeper layers. By a compared evaporation measurement between different WPP designs, the grain size ...
There is a large class of modeling problems where the complexity of the underlying phenomena is overwhelming and hence the accuracy of mathematical models is limited. Our approach to this class of problems is to design frameworks that bring together physically based and data-driven models, and incorporate the tacit knowledge of experts by providing visual exploration and feedback capabilities. ...
High levels of fluoride (beyond 1.5 ppm) in ground water as source of drinking water are common in many parts of Andhra Pradesh, India, causing fluorosis. The study carried out in endemic Nalgonda District, Andhra Pradesh, has indicated that the fluoride-rich ground water present in the wells located down stream and close to the surface water bodies is getting diluted by the low-fluoride surface ...
This research improves field based estimates of aquitard compressibility and permeability. A semianalytical model of partially penetrating, overdamped slug tests achieves this objective. The short term solution is an existing fully penetrating model, the long term solution is the polar residue of an inverse Laplace transform, and an exponential spline function patches the solutions together. ...
Abstract A concept first advanced in 19901, evidence of Low Impact Development (LID) can now be seen across North America. Like many infrastructure transformations, this growth in LID design has benefitted from regulatory changes; compliance versus cost remains an important motivator in any commercial venture. Through their efforts, LID pioneers have demonstrated a range of social and aesthetic ...
Mountain-front recharge, including mountain block recharge and stream seepage, is important for basin aquifers. With the construction of reservoirs in mountainous areas and the recurrent seepage problems of dams, reservoir seepage might become another type of mountain-front recharge. This study identified the recharge sources of groundwater beneath Huangbizhuang Reservoir on the North China ...