Subsequently, new systems are installed and whole buildings are migrated from one supply to another, often leaving disused or deadleg pipework.
As the courses change, buildings have to adapt accordingly. Laboratories, toilets, showers etc are installed, removed or modified which means redundant distribution pipework may be capped and hidden. These deadlegs provide the conditions for legionella to grow and seed other parts of the water system.
It is also extremely important to manage the risk of legionella when schools are closed for holidays etc. These periods provide the perfect opportunity for bacterial growth within the water systems and therefore all water storage tanks, calorifiers and outlets should be thoroughly flushed prior to the start of a new Term. It would be prudent to consider screening the water services for legionella bacteria and Drinking Water quality as part of the regime.