Project Description

Northallerton County Hall


County Hall Campus in Northallerton, North Yorkshire, England, serves as the headquarters of North Yorkshire County Council (NYCC). The building was opened in 1906 and has also been the headquarters of the North Riding County Council, the NYCCs predecessor, up until 1974. County Hall is at the South Western edge of Northallerton and is now a Grade II* listed building.


Reports of smells in and around Northallerton County Hall Campus had proved overwhelming for some time – so much so that some of the staff working within the hall had taken to wearing masks in the office.

HCS were approached and asked to carry out a thorough investigation to determine what the root cause of the smells were. It was determined that the issue was a failed sewage pump system due to an exhausted 60-year-old installation.

Lee Eaglen Technical Waste Water Manager of HCS, said: “While we do have a contract to maintain the system, it wasn’t cost effective to repair the motors given their age. Yet it was vital to tackle the issue straight away as the leaking effluence was giving off toxic gases Methane (CH4) and Hydrogen Sulphide (H2S) which can prove fatal if inhaled within a confined space.

“While these gases cannot kill when airborne, the smell is revolting, making for a very unpleasant experience for anyone working within the vicinity.”

The solution

HCS proposed to remove the existing pump system and replace with a modern, fit-for-purpose upgrade that would serve County Hall long into the future, not only would this reduce maintenance costs but also reduce energy costs due to the modern energy efficient hardware being supplied and fitted.

Lee said: “There was a lot to consider before making the switch. The job was considered ‘medium risk’ being in a confined space and then there was the danger of handling raw sewage to contend with.”

“Before starting any work, we had to ensure we had the correct permits in place to ensure safety for our team working at height and in a confined space carrying out ‘hot works’.

“This is vital, particularly when working with explosive gases, as a spark from a grinding machine while cutting through pipework could set the whole area alight.

“As well as our own team, we also had to ensure full protection against any member of the public entering the site.”

They also took the decision to erect their own welfare facilities for the project, to eradicate any risk of cross contamination through use of the hall’s own rest rooms and canteen.

With all the correct safety measures in place, HCS set about removing the pump using a crane with a sling around the pump to lift it out.

Diesel pumps were installed as a temporary measure to keep the hall operational, while a new 400 volt Flygt pump weighing 60kg was lifted into place and installed.

Electricians set to work on installing and setting up a brand new electrical control unit with bespoke control panel. This equipment acts as a motor control for the pumping station at ground level and sounds an alarm if there are any causes for concern.

The result

Completed works; from design, implementation through to commission and completion took three weeks, leaving Northallerton County Hall with the reassurance that they now had a fully automated, fit-for-purpose pump system which would serve its staff and visitors every day.

Lee said: “While no one really thinks about how important such a system is to the running of the hall’s washroom facilities, those smells alone will certainly make staff appreciate exactly why it is so important.”