[Report 1956] / Medical Officer of Health, Watford U.D.C. / Borough.

  • Watford (England). Urban District Council.
Date:
1956
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: [Report 1956] / Medical Officer of Health, Watford U.D.C. / Borough. Source: Wellcome Collection.

    18/46 (page 14)
    2. The supply from Watford Fields Pumping Station, which is about one third of the total supply, was softened by the lime softening process. It was anticipated that softening of the other two thirds of the supply i. e. the supply from the Grove Pumping Station, would be in operation towards the end of 1956, but this expectation was not fulfilled owing to delays in the completion of the contracts, commenced in May 1955, for the erection of the necessary buildings and structures and the installation of the base exchange softening plant and aeration plant. Although outside the scope of this report, softening at the Grove Pumping Station commenced in April 1957. Since that date therefore the whole of the supply throughout the Corporation's statutory area has been softened water. 3. The Corporation's water undertaking is one of four selected by the Ministry of Health to carry out the initial fluoridation of the public water supply in Great Britain, The fluoridation plant was put into operation at both sources of supply in May 1956 and a close approximation to a fluoride content of 1 part per million, the content pres¬ cribed by the Ministry, has been satisfactorily maintained since that date. Colorimetric tests of the fluoride content of water going into supply are carried out twice daily at both pumping stations and once daily of samples drawn from four points in the distribution system. In addition, four samples (one from each pumping station and two from the distribution system) are taken weekly and sent to the Govern¬ ment Chemist's Department for test by the distillation process, which in addition to 'being a test of the fluoride content is also a check on the accuracy of the colorimetric tests carried out by the Water Department personnel. Finally, a monthly report is made to the Government Chemist setting out the weight of fluoride used each day allied to the quantity of water treated, and the resultant fluoride content by calcula¬ tion and as found by the tests, 4. Bacteriological examinations of the supply were made regularly, by the Counties Public Health Laboratories, London, as follows:- Watfo^d_Fields_Supp^;- Raw Water Treated Water High Le vel Reservoir Low Level Reservoir Monthly Weekly Monthly Fortnightly. Chlorine residual tests of the water leaving the pumping station were taken hourly, and the supplies from the High Level and Low Level Reservoirs were similar¬ ly tested, at 4 - hourly intervals and twice daily respectively.