drenotube® installation guide – DRAIN FIELDS
Important ! – drenotube® may be installed on sites that meet all local criteria for the installation of drain fields. Soil has to be permeable in order to infiltration to occur. Clay or limestone soils are not suitable for drenotube® The product must be installed in compliance with any local health department rules or design requirements. Take into consideration that these requirements may imply the modification of the installation steps mentioned below.
Roots find for water an can damage any drainage system. If necessary use herbicides and sub-surface screen foils to avoid roots from coming into the pipe. Use the same techniques as for a traditional drainage.
1. Identify and Mark area to be infiltrated.
Determine where infiltration needs to be placed (size and layout for the drenotube® system). Mark with paint or stake the location of trenches and lines. Set the correct tank, header line or distribution box and trench bottom elevations before installation of drenotube®
2. Digging the Trench
Maximum trench depth shall not exceed 1m. The trench shall be dug to a width around 95 cm for IF300L3/6 or 115 cm for IF370L3/6 to allocate 3 adjacent bundles ( one centermost bundle containing the pipe (Ref.IF) and two bundles without pipe (Ref BD) one at each side). As any infiltration system intended to transport fluid by gravity, the trenches for the system must be downgrade from the tank and distribution system. The trench shall be level in all directions (both across and along the trench bottom) with all continuous cylindrical bundles placed end to end, with the central bundle and distribution pipe interconnected, without any dams, stepdowns or other water stops.
Cross section of different trench configurations. The minimum backfill depth is 30 cm and the maximum depth of the trench 100 cm
Connection of the drenotube® draining segments (bundles).
Remove the protective drenotube® shipping bag prior to placing bundles in the trench. Place the drenotube® units end to end along the trench and connect to the distribution pipe. Units are printed longitudinally with a line displaying the words “This side up”. Bundles must be installed positioning this line upwards. The uncovered part (1/4) must be placed facing the bottom of the trench. In case you need a shorter segment to end the line, the installation units can be cut and retied with the original tie, wire or duct tape. Excess beads can be dumped into the trench. At the end of the lines drenotube® is normally connected to a vertical hook-shaped aeration pipe.
Placement in the bottom of the trench.
Drop bundles into the trench (be sure to precisely position “This side up” upwards). drenotube® bundles are flexible and can fit in curved trenches as it may be necessary to avoid trees, boulders, or other obstacles. The center-most units containing the pipe are joined end-to-end with an external pipe coupler. Outer units, without pipe, shall be butted against each other and do not require any type of connection. Lead or header lines from the distribution box or such devices shall be connected to the center-most drenotube® (unit with pipe) in each trench.
1 – drenotube® bundle with pipe
2 – drenotube® bundle without pipe
3 – Distribution box
4 – Distibution pipe
5 – Line from treatment station
6 – Click-fit connector
7 – Aeration pipe
Trench closure / Backfilling
Before backfilling the trench make sure there is no plastic bags on top of the drenotube® Check again the longitudinal line displaying the words “This side up” is positioning upwards. Fill the trench with a permeable soil. Do not backfill with impervious soils like limestone or clay. Backfill can be compacted by either manual or mechanical means. Never exceed the ring stiffness of the corrugated pipe. The soil to cover over the infiltration field shall be a minimum of 20 cm in depth. To prevent the ponding of surface water, final soil cover shall be a uniform depth over the entire infiltration field and graded to shed surface water. After proper preparation of the surface, soil cover shall be placed over the infiltration field and suitable vegetation (e.g., turf, sod or seed) shall be used to stabilize the soil surface.