Thames Water are hoping to ‘put things right’ after tonnes of sewage seeped into the River Crane after a sluice gate jammed closed.

The gate jammed shut on Saturday the 29th of October and could not be opened until 8am on Monday the 31st. Unfortunately the gate was on one of the main sewers serving Heathrow Airport and Thames Water had no choice but to let the sewage enter the river or otherwise face major problems at Heathrow.

Some of the sewage which backed up was able to be pumped into tankers and was taken away for treatment. However, there was simply too much sewage for this method to be sustained.

Thames Water Chief executive Martin Baggs stated:

“The Crane has been much improved as an urban wildlife habitat and an attractive natural resource for the community in recent years mainly thanks to hard work of local volunteers, who are understandably upset to see their river suffer major environmental damage over much of its length,

“We deeply regret this incident and we are committed to put things right over the long term.

“We will start that process by meeting this week with representatives from FORCE (Friend of the River Crane Environment), London Wildlife Trust, local anglers and the Environment Agency, so we can fully understand the extent of the damage, and what needs to be done to repair it.”

Drain maintenance engineers finally used a custom built lifting device to open the gate in the trunk sewer under the A4.

Thames Water has started work on the replacement of a sewage pipe in Mortimer which has burst a number of times over the last few years.

The pipe in question, in Tun Bridge, has experienced problems four times over the last five years and will be repaired using the latest ‘no-dig’ technology.

The existing pipe will be repaired using a 300 metre length of pipe liner, which should put an end to the recent problems.

The capital delivery manager for Thames Water stated:

“There is no place for sewer flooding, and we’re all too aware of the inconvenience caused when a pipe, such as this one, bursts. The aim of this project is to put an end to all that.

“We will lay the new pipe using ‘no dig’ technology, which avoids having to dig an open trench along the entire stretch of the road. The majority of our work will be carried out in nearby fields, although there will be some work on The Street.

“We’re in a hurry to complete this essential work before Christmas to give people peace of mind by preventing future bursts.”

No road closures will have to be made while the works are carried out and Thames Water hopes the works will be completed before the busy Christmas period.

It may be the case that when jetting fails to remove the blockage in a drainage pipe that a drain maintenance expert will have to resort to a CCTV survey. A CCTV survey won’t just give the drainage professional information about what is causing the problem; it will also accurately locate the blockage site so the correct method of repair can be chosen.

Survey imaging using CCTV cameras

Drainage engineers use small CCTV cameras which they insert into the drainage system so images of the inside of the drain can be viewed on a computer screen. By viewing the drainage problem in detail the engineers can clearly indentify the problem and can give an accurate quote for the drainage repairs.

Some of the problems a CCTV survey may indicate include:

• Root ingress into the drainage system
• A foreign object blocking the drain
• Drainage pipe subsidence
• Cracks or breaks in the drainage system

CCTV surveys are an invaluable tool in the drain cleaning expert’s arsenal. And when used correctly are an essential part of drain cleaning and drain maintenance.

Thames Water has pleaded with residents to stop putting fat, grease and other non-degradable items into the public sewer system.

The London drainage company has seen a huge rise in the number of pollution incidents this year and has recorded 22 of the worst category events. This compares to the ten events recorded in total in 2010.
In October more than 5,000 fish were killed when two gallons of cooking fat were disposed of down a manhole cover in North London. The fat ended up in a lake in Elstree killing all its wildlife.

Thames Water wants to highlight the problems of putting fat down the drain, which causes ‘fatbergs’ in the drainage system, and is also trying to educate people regarding what can be flushed down the toilet.

The quality and compliance manager at Thames Water, John Sullivan, stated:

“Every single pollution incident is deeply regrettable and we are working hard to try and prevent these happening where we can.

“While we are improving our own practices and investing in further training for our staff, we are also asking our customers to help us prevent blockages.

“Our ‘Bin it – don’t block it’ campaign aims to educate the public about what you can and can’t dispose of down your drains. Basically, if it’s not water, human waste or toilet roll it should not go down the drain. The drains connected to your home were not designed to cope with anything else.”

There are many reasons why drains can become blocked, but one problem that drainage companies face on a regular basis is root infiltration into the drainage system.

Pipes can become blocked by roots when they find their way into the drainage system. They do this by finding tiny cracks in pipes and by working their way though corroded or damaged sections where pipes join together. Once the roots have entered the drainage system they quickly multiply due to the abundant source of water and can soon block the passage of waste water completely.

Drain maintenance engineers can get rid of the roots that may have entered your drainage network. They use a spinning root cutter, which is the same diameter as the pipe, to cut through any roots and associated debris. When the roots have been cut back, the pipe damage may be revealed. However, instead of a section of pipe having to be replaced, most drainage companies now use ‘no dig’ technology to repair the pipe.

One of the most common types of no dig repairs involves inserting a resin impregnated liner into the pipe and positioning it across the area of damage. When the liner sets, the pipe is completely repaired and its waste water carrying capacity is restored.