Annalise Lister from the Cambridge Water Company gave a very interesting talk about the supply of water to Cambridge and district in the past through to the present day.
The Kings ditch was dug in 1230 which meant that the town was surrounded by water, but since these waters were fundamentally open sewers they were not fit to drink, so everyone drank beer. At least boiling the water during the beer making process killed most of the bacteria present. In 1300 the Greyfriars constructed a conduit to bring spring water to Kings, and by 1574 the Kings ditch had become so polluted that water from Nine Wells was used to flush it out. The runnels that are fed from Nine Wells today, and are dry more often than not, are the responsibility of the City Council, and nothing to do with Cambridge Water.
In 1852 a company was formed to source water from Cherry Hinton well and pump it by beam engine to the reservoir on Limekiln Hill. Water was also obtained from a well at Fulbourn, but an outbreak of typhoid in the 1900s led to its discontinuance and one at Fleam Dyke was substituted.
The water from these chalk bore-holes was very hard, so a large building with water softening equipment was built. By 1963 the company was tasked with supplying a wider area around Cambridge, and the decision was taken to no longer soften the water. In 1989 the company was privatised and sold to a Spanish company. The softener building was converted to become the head office. Further sales led to Hong Kong ownership in 2002, and Staffordshire Water in 2011 which continues to the present day.
All our water comes from the chalk and is owned by the Environment Agency whose consent has to be obtained for new boreholes such as the one at Euston, near Thetford, which is the current main source. Water towers like the one at Bluntisham are built on high ground to give the best gravitational flow. The one at Linton is no longer in use.
Water quality is a very important issue. Phosphoric acid is added to prevent lead from pipes polluting the water, and chlorine to act as a disinfectant. Nitrate removal is an important but expensive exercise, so a great deal of effort is being made with farmers to practise good water catchment sensitive farming. This is not a quick fix solution. The water being pumped now has taken many years to reach the aquifers, but it will help in the long term.
Compared with other water companies, Cambridge Water is far from the worst in managing water leaks, but it is important to report any found quickly. Even if the leak is on the householder's own property, in many cases the company may be able to help. The average household uses 150 litres per day and 68% are on meters, but there are simple things that can be done to reduce use, such as having showers instead of baths. Many devices are available free on the company website. If you are approached on the doorstep by someone claiming to be from the company, do not let them in without seeing their identification. Normally they will only come by appointment.
For the future the most important thing is security of supply. Automatic meter reading will come, and focus groups are being consulted about what they want for the future.