The UK has had a wide range off manhole types, mainly concrete and brick construction, installed over the years.

Manholes can be found in all type of infrastructure, Sewers and drains, surface water control, industrial plants of all types, chemical plants, foods processing plants, breweries, refineries etc.

Older manholes were made from engineering and vitrified brick that have

excellent resistance to chemicals and in particular sulphuric acid, formed from the H2S gas generated by microbiological activity in sewage. These

bricks were excellent when first used in the construction of manholes.

Unfortunately the sand / cement mortar mix used to bond the

bricks together has poor resistance to H2S (resulting in sulphuric acid) and

chemical attack, the mortar joints are attacked by the chemicals and


the mortar can be significantly reduced in strength and consequently affecting the bonding of the bricks and the structural integrity of the manhole.

Similarly chemical and H2S attacks on unprotected concrete manholes reacts in the same way, attacking the cement in the concrete and reducing its strength, dissolving the bond between the aggregate, sand and cement mix resulting in the eroding the surface and exposing rebar in some extreme cases.

The symptoms of this type of damage to manholes are displayed as infiltration issues (through brick joints, concrete ring joints, penetrations) causing overcharging of the downstream treatment plants, exfiltration leading to pollution and environmental issues, structural failure, damage or complete destruction to the concrete benching and pipe connections, wash out of backfill and surrounding ground subsidence.

We have solutions for all aspects of dealing with manhole, pumps station and

wet well problems.

We visit site, survey and examine the problem, (all our operatives are confined spaces certified), we will recommend and quote for a solution to the problems identified that can include;

• Leak sealing

• Preparation and cleaning of the manhole surfaces

• Repair of benching, mortar joints, replace missing concrete, repair and restore and protect re-bar.

• Application of protective coating.

Check and sign off and issue guarantee for completed work.

Contact us on 0747 8900998 or visit us at www.powercoatings.co.uk.