What Is Off-Mains Drainage?

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    More than a million properties in the UK countryside send their wastewater to off-mains drainage systems. If you’re buying a rural residential/commercial property described as having no mains drainage, you may well be wondering exactly what this means.

    Fortunately, the Mega-Rod Bath drainage specialists are in an ideal position to help you. As Somerset is one of England’s most rural counties, numerous property owners here and in the surrounding area depend on us to keep their septic tanks and other off-mains drainage systems working properly.

    Let’s explore what off-mains drainage is, what owning a building without mains drainage entails, and why it’s advisable to get a homebuyer’s drain survey or commercial drain survey before finalising your purchase of a rural property.

    Not All Properties Are Connected to Sewers

    The vast majority of UK homes and businesses have mains drainage, i.e. their drains are connected to the public sewer network. Sewers take wastewater to sewage treatment works so that it can be cleaned then released into watercourses.

    However, buildings such as cottages, farms, country hotels and rustic pubs are often too isolated to be connected to sewers. They require off-mains drainage systems instead, which collect and, in some cases, process wastewater on-site instead of sending it to the sewers.

    The Three Types of Off-Mains Drainage

    A property with off-mains drainage will be served by one of the following underground facilities:

    Cesspit

    Cesspits are large tanks shaped like capsules and made of concrete, fibreglass or plastic.

    As the most basic form of off-mains drainage, a cesspit is only designed to store wastewater and doesn’t process it.

    Cesspits need emptying several times per year by a licensed waste disposal company to avoid overflowing due to a build-up of solid waste. We empty them with the aid of a powerful suction pump and tanker.

    Septic System

    Septic systems consist of septic tanks and drainage fields. The tanks are much like cesspits except they’re spherical or cylindrical, while drainage fields contain subterranean perforated pipes.

    Unlike cesspits, septic systems process wastewater so that it can safely merge with groundwater. They do this with the help of gravity and bacteria.

    A septic tank normally has two chambers. In the first one, solid waste sinks and is partly broken down by bacteria while less dense waste (such as oil) floats. Those layers of waste are left behind as the wastewater proceeds to the second chamber, where it’s separated from smaller waste particles.

    Next, the wastewater enters the drainage field. After seeping out of the pipes, it encounters bacteria in the soil, which remove contaminants that weren’t filtered out in the tank.

    Because septic tanks release wastewater, they don’t fill up quickly. Septic tank emptying is therefore carried out less often than cesspit emptying – usually yearly for our customers.

    Sewage Treatment Plant

    The most advanced off-mains drainage systems are sewage treatment plants. According to one UK supplier, the wastewater these facilities release into the environment is typically 97% clean.

    Sewage treatment plants resemble septic tanks except they have compressed air pumps powered by electricity. Wastewater is filtered so that large pieces of debris, such as sticks, don’t reach the first chamber. Layers of solid and light waste form in there, as they do in septic tanks. The remaining wastewater enters the second chamber, where the pumps encourage aerobic bacteria to grow and digest smaller waste particles. Further treatment processes such as disinfection may also be used. The treated wastewater gathers in the third chamber and then enters a watercourse.

    We also empty sewage treatment plants. As with septic tanks, annual emptying is usually sufficient.

    Inspecting and Emptying Off-Mains Drainage Systems

    If you’re buying a property with an off-mains drainage system, it’s vital to check what condition it’s in, as you’ll be legally responsible for maintenance and repairs. That’s where our drain camera surveys for homebuyers and people purchasing commercial buildings come in.

    Thanks to our CCTV drain cameras and expertise, you’ll understand exactly what’s happening underground. A pre-purchase survey protects your interests – if major problems are discovered (structural damage, say), you can renegotiate or pull out of the sale.

    If you do move in, yearly CCTV drainage surveys will help you to nip any problems in the bud. Plus, we can empty your off-mains drainage system efficiently and on schedule.

    Off-Mains Drainage Experts Based in Bath

    When you need help with a residential/commercial off-mains drainage system in Bath, Bristol, North Somerset, North Wiltshire, West Wiltshire or South Gloucestershire, you can rely on Mega-Rod.

    We’re the trusted providers of a comprehensive range of drainage services.

    Don’t let off-mains drainage issues stop you from enjoying life in the country – call Mega-Rod today on 01225 422980.

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      Need your drains unblocking? Septic tank need emptying? Need a CCTV Drain Survey? Contact the experts at Mega-Rod on 01225 422980. We offer a prompt, competitive service from a family firm working in Bath, Bristol and the surrounding area.