Everything you need to know about manholes

Introduction

Manhole covers - we see them all the time, particularly in built up areas, but what are these metal squares actually for? As a drainage contractor, we see a huge amount of manhole covers and the chamber they conceal every week, so below we’ve answered a few FAQs about these drainage features… 

What is a manhole?

In the UK, a manhole is a covered opening to the underground sewerage systems that serve our homes and businesses, providing an access point for trained personnel to inspect, clean, unblock, or repair the drainage system. 

Manholes consist of a lid around 4-5ft in size, frame, and chamber, in which lies wastewater, which can be foul and/or an accumulation of rain; they can generally be found at regular intervals in urban areas, such as gardens and pavements. From this chamber, the wastewater can be taken in several directions.

What is the history of manhole covers? 

Believe it or not, the Romans were the first to develop underground sewerage systems - as you may expect, the access point lids back then were more like artwork than the cast iron iterations we see today.

You’ll find that the appearance of manholes varies depending on the area and the manufacturer - some are plain, whereas others feature patterns and shapes. The use of manhole covers as we recognise them today date back to the late 1800s, so expect to see a far few variations, particularly in areas such as London.

Who is responsible for the maintenance and repair of manholes?

Because of the urban nature of manholes, there can initially be a question mark over who is in charge of maintenance and repairs - is it the local council, utility companies, or private property owners? This, luckily, is clearly defined by the rule that, if the manhole cover is within the boundaries of your property or it only serves your property, you are responsible for maintenance and repair. If the manhole cover is on a public road or footpath, the local water authority is responsible for repairs and maintenance. 

What should you do if a manhole cover is damaged?

If the manhole in question is on a public road or footpath, you should report it to the local water authority immediately, particularly if it’s posing a safety risk to pedestrians, cyclists, and/or vehicles. 

If the damaged manhole cover is within the boundary of your property, you should engage a local drainage specialist, who will be able to source a replacement frame and lid and install it for you at your cost. Do what you can to prevent anyone crossing the damaged manhole if it’s a safety risk in the meantime. 

How can you tell if a manhole is blocked? 

Often, the following issues will alert you to a problem lurking beneath a manhole cover: 

• A foul smell
• Slow drainage within your property
• High water levels beneath the manhole lid
• Gurgling sounds emitting from under the manhole cover
• Flooding around the manhole

If you notice any of these problems, prompt action gets things flowing again as quickly as possible – the issue is very unlikely to go away on its own!

Is it illegal to cover a manhole cover? 

Let’s face it, manholes aren’t the prettiest part of paving in the world, but if you’re looking to permanently cover a manhole within the boundaries of your property, you should do so in the correct way. Manholes are access points, after all, and the free-flowing nature of your drainage may one day depend on it.

In short, you must not permanently block a manhole cover in a way that restricts access, and you must seek permission from the local authority if the plans you have involve permanently covering an existing manhole, such as having an extension built. 

How are blocked manholes unblocked? 

If a blockage within the drainage system can be accessed by a manhole, drainage contractors will use either rods or highly powered jets to tackle the blockage. This is why you find so many manholes in urban areas - they allow contractors to get as close to the blockage as possible in order to deal with it. 

In this modern world, they’re also the point at which CCTV equipment is placed into the system, to remotely pinpoint the cause of any problems.

What causes a blockage under a manhole?

A blockage under a manhole relates to a larger blockage within the drainage system, and this can be caused by a number of issues. They include: 

• A buildup of kitchen grease and fats 
• Objects put down drains and toilets that are unsuitable for the drainage system, such as nappies
• Garden debris, such as leaves and branches 
• A collapsed drain 
• Tree root ingress 
• Heavy rainfall 

How can I stop a loose manhole from making noise? 

Manholes on public roads and footpaths that are causing a disturbance should be reported to the local water authority, as they may be able to refix, replace, or soundproof the noisy manhole. If the manhole that’s rattling or otherwise making a noise is within your property boundary, seek advice from a drainage contractor, who may be able to secure or soundproof the manhole to reduce the noise it makes. 

Choose The Drain Guys for manhole maintenance in the South East

Whether there’s a blockage beneath the manhole on your property that urgently needs attendance, or you’re seeking advice about repair or replacement, we’re the experts to trust in the Sussex area. With teams across major towns and cities in the South East, such as Brighton, Worthing, Chichester, and Tonbridge, we’ll be able to find a convenient solution that suits you.

The Drain Guys are a knowledgeable, friendly bunch with years of experience, so rest assured you’ll be in safe hands when you give us a call.