Backfilling .................. Placement of excavated soil in the trench after blinding has been completed.
Bedding ....................... The earth foundation of the trench together with the select material around and over the drain, including envelope and filter material where used.
Berm .............................. Strip or area of land, usually level, between the spoil bank and the edge of a channel or ditch.
Blinding ........................ Placement of select soil around a drain to prevent damage or misalignment when the trench is backfilled and to allow water to flow freely to the drain.
Coefficient of roughness Factor expressing the frictional resistance to flow of a channel surface or a drain interior.
Connections ............... Fittings used to join two drain lines.
Continuous pipe ...... Extended length of pipe without perforations or unsealed joints.
Deflection .................. Decrease in vertical diameter of tubing, often influenced by loading.
Ditch ............................. Constructed open channel for conducting water. See Drain.
Diversion .................... Channel constructed across the slope for the purpose of intercepting surface runoff.
Drain ............................. Conduit below the ground surface for removal of surplus ground or surface water. See Ditch.
Drainage area ........ Area from which drainage water is collected and delivered to an outlet. Sometimes referred to as the watershed area for a particular drain.
Drainage coefficient The depth of water, in inches, to be removed from an area within 24 hours.
Drainage system .. Collection of surface ditches or subsurface drains, together with structures and pumps used to collect and dispose of excess surface or subsurface water.
Field ditch ................ A graded ditch generally crossable with field equipment for collecting excess water from a field.
Grade or gradeline Degree of slope of a channel or natural ground.
Inspection well ...... Opening to surface in drain line to permit observation of flow conditions.
Interceptor line or drain Surface ditch or subsurface drain, or a combination of both, designed and installed to intercept flowing water. Also, a line used to intercept several lines to keep the number of crossings at highways and similar locations to a minimum (also called collector lines).
Junction ...................... Point of intersection of two or more surface ditches or subsurface drains.
Lateral ditch ........... Principal channel or ditch that conducts drainage water from the field ditches to an outlet channel.
Lateral drain ........... Secondary drain that collects excess water from a field.
Main drain ................ Principal drain that conducts drainage water from the lateral drains and submains to an outlet.
Outlet channel ........ Channel constructed primarily to carry water from manmade structures such as drain lines, surface ditches, diversions, and terraces.
Pipe ................................ A continuous length of non perforated conduit typically used to protect an outlet or to provide additional structural strength.
Pipe drop inlet ...... Type of surface water inlet, fabricated from pipe materials, which lowers surface water to a ditch bottom.
Pumping plant .......... One or more pumps, power units, and appurtenances for lifting drainage water from a collecting basin to a gravity outlet.
Slope ............................. Degree of deviation of a surface from the horizontal, usually expressed percent or a ratio of horizontal to vertical (i.e., 4:1).
Slot ................................ Perforations in plastic tubing. Also, the opening in the ground created by the trench less plow as it lays the tubing.
Spoil bank ................. Soil excavated from channel, ditch, or other site and placed along the excavation site.
Stretch ....................... The increase in length of the tubing caused by tension forces during installation. It is expressed as a percent increase of the length prior to installation.
Submain ...................... Branch drain off the main drain which collects discharge water from laterals or from the field.
Tile ................................. Drains made of burned clay, concrete, or similar material, in short lengths, usually laid with open joints to collect and carry excess water from the soil.
Tubing .......................... A flexible drain that gains part of its vertical soil load-carrying capacity by lateral support from the surrounding soil.
Watershed ............... Total land area above a given point on a stream or waterway that contributes runoff to that point.
To convert Into Multiply byacres hectares 0.405acres square feet 43,560acres square meters 4,047acres square yards 4,840centimeters feet 0.0328centimeters inches 0.394centimeters meters 0.01centimeters yards 0.0109cubic feet cubic inches 1,728cubic feet cubic meters 0.0283cubic feet gallons 7.48cubic feet liters 28.3cubic inches cubic feet 0.00058cubic inches gallons 0.0043cubic inches liters 0.0164cubic meters cubic feet 35.3cubic meters cubic inches 61,023cubic meters gallons 264.2cubic meters liters 1,000feet centimeters 30.48feet inches 12feet meters 0.305feet yards 0.333gallons cubic feet 0.134gallons cubic inches 231gallons cubic meters 0.0038gallons liters 3.79hectares Acres 2.47hectares square feet 107,600hectares square meters 10,000hectares square yards 11,956inches centimeters 2.54inches feet 0.083inches yards 0.0278kilometers feet 3,281kilometers meters 1,000kilometers miles 0.62kilometers yards 1,094To convert Into Multiply byLiters cubic feet 0.0353liters cubic inches 61.02liters cubic meters 0.001liters gallons 0.264meters centimeters 100meters feet 3.281meters inches 39.37meters kilometers 0.001meters yards 1.094miles feet 5,280miles kilometers 1.61miles meters 1,609miles yards 1,760square centimeters square inches 0.155square centimeters square meters 0.0001square feet square inches 144square feet square meters 0.0929square feet square yards 0.1111square inches square centimeters 6.45square inches square feet 0.007square inches square meters 0.00064square meters hectares 0.0001square meters square centimeters 10,000square meters square feet 10.76square meters square inches 1,550square meters square yards 1.2square yards square feet 9square yards square inches 1,296square yards square meters 0.8361yards centimeters 91.44yards feet 3yards inches 36yards meters 0.914