Tanker Services in Dorchester

What are drainage tanker services?

Drainage tanker services remove liquid waste in bulk, using a vacuum tanker to empty tanks, chambers and interceptors that are full rather than blocked.

Some drainage jobs are not blockages at all. A septic tank that has filled with sludge, a cesspit at capacity, a flooded chamber or an interceptor full of silt and oil all need their contents taking away, and no amount of rodding or jetting will fix them. A tanker sucks the contents out through a hose and carries them away for proper disposal.

We provide tanker work for homes, businesses and sites in Dorchester and the surrounding villages we cover, either as a one-off or on a regular schedule agreed with you.

Which tanks and systems can be emptied by tanker?

Most drainage systems that hold liquid can be emptied by tanker, from domestic septic tanks to commercial interceptors and flooded chambers.

• Septic tanks and cesspits on properties not connected to the mains sewer
• Package sewage treatment plants that need desludging
• Grease separators serving commercial kitchens
• Oil and petrol interceptors in car parks, forecourts and workshops
• Silt traps, gully pots and catch pits on surface water systems
• Pump station wet wells and sumps
• Chambers and drains that have flooded after a blockage or a pump failure

If you are not sure what kind of tank you have, describe where it is, what it serves and what the lid looks like when you call. That usually tells us enough to plan the job.

What is the difference between a septic tank and a cesspit?

A septic tank separates solids from liquid and lets the treated liquid flow out to a drainage field; a cesspit is a sealed tank with no outlet that simply stores everything until it is emptied.

In a septic tank, solids settle as sludge and the liquid passes on to soak into the ground through a drainage field. Only the sludge and scum build up, so it needs emptying far less often than a cesspit.

A cesspit holds every litre that goes into it, so it fills in proportion to how much water the property uses. A busy household can fill one quickly. A package treatment plant is different again: it uses air and bacteria to treat the waste more fully, but still needs its sludge removing regularly.

How often should a septic tank or cesspit be emptied?

A septic tank is commonly emptied about once a year, depending on its size, how many people use it and the maker's guidance. A cesspit needs emptying whenever it nears capacity.

For a septic tank, the aim is to remove sludge before it builds up far enough to escape into the drainage field, where it clogs the ground and can cause the whole system to fail. A small tank serving a large household may need emptying more often than once a year.

A cesspit's interval follows water use. Some fill in weeks, others in a couple of months. A high-level alarm, if fitted, warns before it is full. Reducing water use, such as fixing dripping taps and running full loads, stretches the interval.

What are the signs a tank needs emptying?

The usual signs are slow toilets and drains across the property, sewage smells near the tank, and in a septic system, wet or unusually green ground over the drainage field.

Other warnings:

• Gurgling from plugholes and toilets
• A cesspit level alarm sounding
• Liquid seeping from the tank lid or around chambers
• Sewage backing up into the lowest fittings in the property
• An interceptor alarm, or oil visible in the final chamber
• A grease separator with fat visible in the outlet

If sewage is backing up into a property or escaping onto the ground, stop using water where you can and treat it as urgent. We take calls 24/7.

How does a tanker visit work?

We agree the job and access in advance, position the tanker as close as practical, empty the tank through a hose, check it and leave you the waste paperwork.

• When you call, we establish the type and approximate size of the tank, where it is and how close a vehicle can get
• We agree a fixed price and a time
• On site, the hose is run from the tanker to the tank and the lid is lifted
• The contents are removed, breaking up any crust or set sludge so the tank empties fully
• The tank's inlet, outlet and visible condition are checked
• Any fault, such as a cracked lid, a blocked outlet or signs of a failing drainage field, is reported to you
• The lid is secured, the area is cleaned down and you receive the waste transfer note

What access does a tanker need?

A tanker needs to park within hose reach of the tank on ground that will take its weight, so how close it can get decides what is possible and what it costs.

Things worth telling us when you call:

• How far the tank is from where a large vehicle can park
• Whether the route has narrow lanes, low branches, gates or weight limits
• Whether the tank is uphill or downhill from the road
• What the ground is like, such as a soft lawn, gravel or a hard drive
• Whether the lid is buried, heavy or hard to find

Long hose runs and difficult lifts are often possible, but they change the vehicle and equipment needed. Knowing in advance means we arrive with the right ones rather than making a second trip.

How long does tank emptying take?

Emptying a domestic septic tank or a small interceptor usually takes an hour or two on site. A large cesspit, commercial separator or flooded system takes longer and may need more than one load.

The time depends on the volume of the tank, how thick the sludge is, how far the hose has to run and whether the lid and inlet need work to access. A tank that has gone a long time without emptying usually has a hard crust and dense sludge that take longer to break up.

If the volume is more than one tanker load, we tell you before we start, because it affects both the time and the price.

What tankering can and can't fix

Emptying removes what a tank holds and gives it room to work again. It does not repair a cracked tank, unblock a failed drainage field or fix a drain that is broken on the way to the tank.

If a septic tank fills back up within days of emptying, the problem is usually beyond the tank: a drainage field that has stopped taking water, or groundwater getting in through a crack. A cesspit that fills faster than water use explains may be taking in rainwater or groundwater.

Where we see signs of those problems, we tell you what we saw and suggest the next step, which may be a camera survey of the pipes or an assessment of the drainage field. Nothing beyond the agreed emptying is done without your agreement.

How much does tanker emptying cost?

The cost depends on the volume removed, the type of waste and its disposal charge, the length of hose run and how difficult the access is.

As a guide, emptying a standard grease trap typically costs £150 to £300. Septic tanks and cesspits are priced on their capacity, so a larger tank costs more.

Your fixed price is agreed before the tanker is sent out. If the job changes on site, for example because the tank is larger than described or needs a second load, we stop, explain why and agree the extra before continuing. Setting up regular emptying lets the price for each visit be agreed in advance.

Where does the waste go, and what paperwork do you get?

The waste is taken by a registered waste carrier to a site permitted to accept it, and you receive a waste transfer note that records what was removed, how much and where it went.

Under the duty of care, a business must make sure its waste is passed only to an authorised person and must keep the transfer note. Transfer notes have to be kept for a minimum of two years in England. Householders also have a duty to check that whoever removes their waste is authorised to carry it.

Some waste, such as oily water from a petrol interceptor, is often classed as hazardous, which uses a consignment note instead of a standard transfer note. Tell us what your interceptor serves, so the right paperwork is used.

Who is responsible for a septic tank or cesspit?

The owner of the property is responsible for its septic tank or cesspit, and where a tank serves several properties, the owners usually share that responsibility, unless deeds or an agreement say otherwise.

For rented homes, the landlord is normally responsible for keeping the system in working order, while tenants should use it sensibly. A shared tank works best with a written agreement on who arranges emptying and how the cost is split.

Septic tanks in England are also covered by the Environment Agency's general binding rules for small sewage discharges. One of those rules meant tanks discharging straight to a ditch, stream or river had to be replaced or upgraded by 1 January 2020. If you are unsure whether yours complies, the Environment Agency publishes the rules.