You can build over a private drain. Building control will inspect the pipework and approve the works as part of your extension. A public drain is a different matter.
Building over or near a pipe could damage the pipe or your home in the long term, so it's important we work together to find out what pipework is underground. We recommend you find out where the lateral drains and sewers are well in advance of starting any building work.
A big risk to building over the drainfield is causing the lines to collapse. Also, the soil can compact around the trenches, which may not allow for percolation. Repairing the drainfield or moving it may require an entirely new system depending on your system age and the regulations for your local authority.
You can build over a drain but it needs to be properly designed and if the drain is public you need permission before you start. So the first thing to establish is whether the drain is private or public?
It is not permissible at all to build directly over a manhole or a pressurised pumping main. You should consider diverting the sewer so that it will be at least three metres awayfrom the building The local water authority could do this. However, it would be at your expense.
If you are building foundations at an angle to the sewer pipe, you can put concrete on either side of the pipe and bridge over it.
You should never install the following over a drainfield:
Driveways. Pools. Patios. Tennis courts.
In general: Your septic tank and leach field should be 100% within your property line, so putting a fence on the outside edge of your property won't be a problem as you won't hit either the leach field or the septic tank.
A minimum horizontal clearance of 1 metre is required around sewer access structures as well as a minimum vertical clearance of 3 metres. The horizontal clearance shall increase to 2 metres if two or more sides of an access structure are built around. A fourth side must be open and accessible at all times.
Yes : If the line is bedded properly and protected by enough materials to prevent crushing of the pipe below . In this case Sch# 40 PVC pipe where allowed and if in a area where frost is present the line should be insulated also . Proper pitch is needed so no water is standing in pipe in that case also .
No. Focused pressure for long periods of time could cause leach pipes to crack or break, even if the vehicle's weight does not exceed 10,000 pounds. Parking on top of leach fields should be avoided.
While the large grassy area above your leach field may seem like the perfect place to build your garage, shed, or barn, building on or near your leach field is not recommended.
How far should I build from my drain field? The setback distance for building near a drain field can vary depending on your location and local regulations. In general, it's recommended to maintain a minimum distance of 50 feet.
A sewage system is an underground network of pipes that holds sewage (normally wastewater mixed with human waste). All drains lead to sewers and all sewers will lead to a local treatment plant to properly dispose and treat waste accordingly.
Imagine stepping on a sponge—if you press down too hard, it loses its ability to soak up water. That's what happens when you park or drive on your drainfield: the soil becomes compacted, and the pipes underneath can get damaged or even crushed.
Any pipe that passes under a footing or through a foundation wall shall be provided with a relieving arch, or a pipe sleeve pipe shall be built into the foundation wall. The sleeve shall be two pipe sizes greater than the pipe passing through the wall.
Build over agreements are required for any building works to existing properties within 3 metres of a public sewer, or within 1 metre of a public lateral drain. This is to prevent damage to the sewer network, and ensures we have suitable and safe access to carry out maintenance and repairs.
Building over a sewer can be a complicated process. It will also require the correct permissions from your local authority and utilities provider. You may also need to redirect drainage and potentially relocate manhole access covers. With skilled and complex work like this, it's always best to hire a professional.
Before constructing a fence within a drainage easement, consult with local authorities and review your property's easement documents. You may need special permissions or need to adhere to specific guidelines to ensure that your fence does not impede drainage.
∎ C overs to drainage systems should not be obstructed by boundary fences. Manholes/inspection chambers should be located to provide adequate access for inspection and maintenance. Where a manhole/inspection chamber is obstructed by a fence, either the fence or the manhole/inspection chamber should be relocated.
Typically, the drainfield consists of three to five trenches that are 18 to 24 inches deep, up to 100 ft long, with a perforated pipe in 12 to 18 inches deep gravel covered by 12 inches of soil.
Put plastic sheets, bark, gravel or other fill over the drainfield. Reshape or fill the ground surface over the drainfield and reserve area.
Extending your house, building a conservatory, garage, or basement/cellar can impact underground sewer pipes. If you plan to build over or near a public sewer, permission is mandatory before starting work.
Grass is the ideal cover for drainfields. Grasses can be ornamental, mowed in a traditional lawn, or in an unmowed meadow. Or, you can try groundcovers and fems. The key to planting over the drainfield is to select shallow-rooted, low-maintenance, low-water-use plants.
Avoid Putting Weight on the Drain Field
Never place, park, or store any heavy objects on your drain field; this means you should never use your drain field as an overflow parking lot. In addition, you shouldn't build any structures on your drain field. This includes building a deck or swimming pool.