Landscape Drainage by Lifestyle Landscaping Solutions, Bundaberg.
In the design of any landscaping project just as it is in construction of a Retaining wall, Drainage is critical to be addressed. Should you overlook drainage control your landscape project is destined to fail. Lets look at some key areas of drainage in Bundaberg. As bundaberg is relatively flat therefore the ability to succesfully drain areas are often more difficult to achieve.
Key areas of Drainage.
1/ Lawn areas surface water
2/ Planter boxes.
3/ Seepage from retaining walls and embankments
4/ Overflow through gardens, from driveways, paths
5/ Pool surrounds.
Surface water from lawn areas.
Surface water is the primary area of concern in most landscaping projects. This issue is often overlooked to the detriment property owners. You must maintain a clear 75mm below weep holes for white ant observation and as a buffer should drainage backup into your property. At times some builders leave the building pad too low into the ground leaving little ability to effectively drain a property. Do not direct roof water into the same stormwater pipes into the same pipes as field grates. The added back pressure from roof water will allow water to flood back through the stormwater field grate onto the lawn area. In some circumstances a “Y” junction can be installed when the distance from the junction is a minimum of 4-6m when the disposal point of the stormwater is below the collection point of the field grate. This will in effect suck the water from the yard. Avoid this option if at all possible, only use then when no other option is available as incorrect installation can cause water to backup. Seek professional advise where you are uncertain of the most efficient technique to drain your project. When connecting several field grates in series take into account pipe sizing in comparison with the size of the catchment area.
Drainage in planterboxes.
Concrete planter boxes are being used more regularly in landscaping careful drainage will avoid flooding the planter when mulch will often overflow or be washed away. Firstly place 100mm of 20-40mm of drainage gravel in the base of the planter, then install a layer of geo-fabric filter cloth to prevent filtration of soil into the drainage gravel. Secondly place “Drainage Cell” vertically along 2 sides of the planter and line with geofabric cloth as well. Leaving the top edge of the drainage cell open to the mulch area. This will provide a direct flow from the top to the bottom of the planter. Problem solved
Seepage from Retaining walls and embankments.
In times of consistent & prolonged rain periods water seeps out of walls and embankments. To avoid becoming a “bog hole” drain coil should be connected to a field grate for connection to a stormwater disposal system. The “slotted” drain coil can either be “socked” or plain slotted drain coil. The socked coil is covered with a sock of filter cloth to prevent siltation of the pipe. Alternately when the pressure from the water source is greater use plain drain coil ( in the appropriate size, 50mm, 65mm or 100mm) placing Geo fabric filter cloth to complete face all edges of the trench. Place 50mm deep of 20mm filter gravel in the base of the trench say 150-300mm wide, place the drain coil on the gravel then fill with gravel to close to the surface folding over the geo fabric across the drainage gravel. Ensure this pipe has natural fall to the dispersal point.
Overflow of water through gardens.
Often gardens are created below lawn areas and the natural flow of water is through the garden. This will generally wash the mulch down the street onto paths etc. To avoid this situation you can dig out the existing mulch to 100mm deep, then lay a layer of geo fabric cloth onto the soil, then place 100mm deep of drainage gravel of various sizes from 20 -100mm will work well. The filter cloth will prevent undermining of the gravel in times of heavy rain. Similarly where water washes from paths and driveways this same solution will work well.
Pool Surround drainage.
Around pools you will find drainage is difficult to achieve without ponding. Over the length of the pool the surrounds are level and often narrow. To achieve natural fall is quite difficult to achieve. Often drainage grates, or strip grates are used to allow water to be directed to these points and into the stormwater system.
When you face a challenge you are not quite sure how to solve the challenge call us at Lifestyle Landscaping Solutions for advise on the best solution for your project. alternately we can provide you with a quotation to complete the work for you. Feel free to call us on 4155 5500 or 1800 EARNIT.
written by Peter Moller, Lifestyle Landscaping Solutions Bundaberg.