When the familiar voice on the London Underground reminds us to “Mind the Gap,” we think of the gap between the platform and the train. But it could also be applied to the gap in our awareness – that this small space, easily overlooked, carries potential danger.
On construction sites, the small and equally overlooked space around a manhole cover can also result in preventable problems – additional costs, delays, damage, and environmental and occupational hazards. Road gullies are another point of entry for problem-causing silt and debris.
All these can be quite simply avoided by installing MuckStopper® Manhole Protection Units during construction.
The Consequences of Construction-Blocked Drains
Financial
The financial risk of ignoring this issue is real. In an earlier post, we highlighted a case when a 100-tonne ‘concreteberg’ blocked the London sewage system, after (it was suspected) a construction firm deliberately poured surplus wet concrete into a nearby drain. While the scale and audacity of this particular incident were unusual, it is an extreme illustration of the havoc that silt from construction sites can cause if it enters drains via manholes or road gullies.
If a construction company commits a deliberate act like this, it should rightly be prosecuted, but even accidental spillages and runoff of concrete, silt, soil and fine aggregates can block drains. Before a contractor hands over a completed project, they have a duty of care to ensure that all drains are unobstructed and functioning correctly. If this contamination has developed slowly over time, the scale of the problem may not be evident, but the cost to remove it can come as an unpleasant and costly surprise.
Operational
If an unprotected manhole or road gully becomes blocked, it can bring construction progress to a halt in various ways. Flooded and waterlogged ground is unstable and unsafe, and can delay or cause landscaping, paving and surfacing to require rework. Heavy vehicle access may be impacted. In extreme cases, structural damage can be caused by soil erosion.
Environmental
The Environment Agency has repeatedly highlighted how construction runoff is a major source of water pollution in the UK. Preventing silt from entering the drainage system in the first place is far more effective – and far less costly – than cleaning up afterwards.
Worker Safety
Obstacles and craters hidden under floodwater can be hazardous to vehicles and pedestrians.
Clearing blocked drains often means sending workers into confined spaces, one of the most hazardous environments in construction. The Health and Safety Executive (HSE) warns that confined space work carries risks of asphyxiation, toxic exposure and entrapment. Reducing the need for workers to enter manholes by stopping blockages before they start is the safest option.
MuckStopper®: A Practical Solution
The MuckStopper Roads & Sewers System from BlueJay Solutions was designed to remove this weak point. Its Manhole Protection Units and Gully Silt Traps provide temporary but robust barriers that stop silt and debris at source.
Manhole Protection Units
Each unit is engineered to fit standard chamber sizes, so contractors can choose the right fit for their site without compromise. A Manhole Protection Unit is temporarily installed under the permanent manhole cover and frame, and features a removable hatch for access to the chamber if required.
The unit captures any silt or debris that may get past the manhole cover and frame, and this can be regularly removed without entering the chamber. On the completion of the project, the manhole cover and frame are lifted, the unit is removed, and then the manhole cover and frame are reinstated before the final surface is applied.
The MuckStopper 600x600 Manhole Protection Unit is purpose-built for standard 600mm manholes, while the 675x675 Manhole Protection Unit offers the same robust performance for this larger size.
For double-lid applications, the 1200x600/1220x675 Unit features an adjustable divider that gives flexibility without compromising on debris control.
Gully Silt Traps
MuckStopper Gully Silt Traps feature a square, galvanised steel bucket with a wide flange around the rim. The flange sits snugly against the gully and deflects water and silt into the bucket, where perforations allow water to drain into the gully while silt and debris are captured. The trap is regularly removed for emptying to keep the gully functioning efficiently.
The MuckStopper Gully Silt Trap 400 is the heavier-duty version, while the MuckStopper Gully Silt Trap 400 Lite offers a more cost-effective alternative for when the same level of ruggedness is not required.
The Prevention That’s Better Than a Cure
By taking a small precaution at the start, contractors avoid the far bigger consequences of project delays, unexpected costs and regulatory headaches. What might seem like a minor detail is, in reality, the safeguard that keeps drainage systems flowing and projects moving.
For more details on the MuckStopper product range and approved stockists, contact BlueJay Solutions on 01420 559888.