Search results
Results from the WOW.Com Content Network
A diagram of a traditional French drain. A French drain [1] (also known by other names including trench drain, blind drain, [1] rubble drain, [1] and rock drain [1]) is a trench filled with gravel or rock, or both, with or without a perforated pipe that redirects surface water and groundwater away from an area.
A French drain is a trench that diverts water away from an area where it's pooling to a lower elevation where it can be released, explains Mike Arnold, director of The Gardens at Texas A&M ...
Infiltration will occur where local groundwater elevation is higher than the sewer pipe. Gravel bedding materials in sewer pipe trenches act as a French drain. Groundwater flows parallel to the sewer until it reaches the area of damaged pipe. In areas of low groundwater, sewage may exfiltrate into groundwater from a leaking sewer. [6]
The French size is a measure of the outer diameter of a catheter (not internal drainage channel, or inner diameter). So, for example, if a two-way catheter of 20 Fr is compared to a 20 Fr three-way catheter, they both have the same external diameter but the two-way catheter will have a larger drainage channel than the three-way.
A French drain, PVC pipe, or other drainage system is installed in the newly made channel. The installed drain is covered with new cement. The drainage system collects any water entering the basement and drains it to an internally placed sump pump system, which will then pump the water out of
Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Donate
Alternatively, the size of a 10 Fr catheter might be expressed as 10 Ch (Charriere units – named after a 19th century French scientific instrument maker, Joseph-Frédéric-Benoît Charrière). The most common sizes are 10 Fr to 28 Fr. 1 Fr is equivalent to 0.33 mm = .013" = 1/77" of diameter.
In practice, it is common to restrict the flow below the value of 0.82D to avoid the region of two normal depths due to the fact that if the depth exceeds the depth of 0.82D then any small disturbance in water surface may lead the water surface to seek alternate normal depths thus leading to surface instability. [2]