Search results
Results from the WOW.Com Content Network
the design drain spacing (L) can be found from the equation in dependence of the drain depth (Dd) and drain radius (r). Drainage criteria One would not want the water table to be too shallow to avoid crop yield depression nor too deep to avoid drought conditions. This is a subject of drainage research.
Culverts come in many sizes and shapes including round, elliptical, flat-bottomed, open-bottomed, pear-shaped, and box-like constructions. The culvert type and shape selection is based on a number of factors including requirements for hydraulic performance, limitations on upstream water surface elevation, and roadway embankment height. [2]
Mollweide projection of the world The Mollweide projection with Tissot's indicatrix of deformation. The Mollweide projection is an equal-area, pseudocylindrical map projection generally used for maps of the world or celestial sphere.
A culvert pipe under a road is a common target for beaver damming because the constriction speeds up the current and may resemble a hole in a dam. With a little work, a beaver can quickly plug a culvert with mud and sticks, and turn the entire roadbed into a large dam.
A pipe laser, or another vertical distance measuring device is most commonly used for this. Invert levels are important for the drainage of a non-pressured fluid pipe. Typically, a good design requires that the invert level of the pipe will be lower (or at least not higher) for each section of pipe before it reaches its final destination. [5]
These elements are large diameter full section or ring section reinforced concrete wells with circular or elliptical cross-sections. The depth of the static wells can reach 30-40m. Often the static stabilising action of the wells is integrated with a series of microdrains laid out radially on several levels, reducing pore-pressures.
As with the small multiple chart, each panel uses the same underlying two-dimensional space, but in this case that is a geographic space. Typically, the variables being mapped are of a similar type, such as types of agricultural products, so that the same strategy of map symbol can be used on each panel, enabling rapid comparison between the maps.
The Croton Aqueduct or Old Croton Aqueduct was a large and complex water distribution system constructed for New York City between 1837 and 1842. The great aqueducts, which were among the first in the United States, carried water by gravity 41 miles (66 km) from the Croton River in Westchester County to reservoirs in Manhattan.