Engineering

Hydrologic design considerations Permeable pavement is subject to the following design considerations, including benefits and constraints. Available space – A significant advantage of permeable pavement is its ability to combine detention/ infiltration and pavement, thereby reducing or eliminating land required for detention facilities. This is especially important in urban areas with high land prices and highly developed sites with little or no space for stormwater detention. Soils – Soil conditions and infiltration rates determine the use of an  underdrain . ( NRCS   Hydrologic Soil Group  (HSG) C or D soils usually require an underdrain, whereas HSG A and B soils often do not.) Designers should evaluate existing soil properties during initial site layout with the goal of configuring permeable pavement that conserves and protects soils with the highest infiltration rates. In particular, areas of HSG A or B soils shown on soil surveys should be considered as pri...

The water treatment plant will treat raw water coming through 26.5 Km tunnel from Melamchi River for the Melamchi water supply project. The ultimate capacity of the water treatment plant will be 510 mld. The plant will be developed in three phases, each of 170 Ml/d. The second stage will be accomplished by duplicating the major facilities of the initial phase, and the third phase will comprise mainly performance enhancements and increased design loading on the facilities constructed under phases 1 and 2. As the first phase of WTP project, the detailed design of the WTP capacity will be done for 170 mld with provision of the future expansion. The design of phase 1 allows for the complete development of the site over the three phases, and some facilities are, therefore, sized for the ultimate capacity. The treated water will then be served to the 1.1 million population of Kathmandu Valley. The water treatment plant is to be located near Mahankal, a village on the left bank of the...