A REVIEW OF THE REQUIREMENT FOR WATER TREATMENT WORKS
PERFORMANCE SPECIFICATION
Report No FR0089

Apr 1990

SUMMARY

I OBJECT

The initial objective of this contract was to produce guidelines for water treatment works performance specification, over a two year contract period. The contract period was then reduced to one year, and the objective modified to produce, primarily a review of procedures to be taken into account in the preparation of water treatment works performance specifications.

II REASONS

For the successful completion of "design and construct" contracts for water treatment plant, it is important that the client Water Undertaking provides the contractor with clear, unambiguous information on raw water quality and the required plant performance. Guidelines stipulating the nature and extent of information needed by client and contractor would assist in the selection and design of suitable treatment processes, and could avoid dispute over whether or not performance standards have been achieved.

III CONCLUSIONS

The production of performance specifications for water treatment works is made more complex than for other process industries by the variable and largely uncontrolled nature of the feedstock (raw water). The situation is further complicated by the implications of 100% compliance with EC Directive standards for drinking water. The report discusses these and other factors to be taken into account when producing performance specifications, and gives guidance where appropriate.

IV RECOMMENDATIONS

The information given in this report can be used to assist with the production of performance specifications. Further work is needed to improve and develop this information, particularly with regard to:

• the statistical definition of treated water quality,
• prediction of works performance based on raw water quality and laboratory test procedures.

Both of these areas require a major programme of sampling and  testing of existing treatment works.

V RESUME OF CONTENTS

The report reviews legal, statistical and technical aspects of raw and treated water quality and process performance, in relation to the production of performance specifications for water treatment plant. The results of preliminary work using jar test procedures to predict treatment works performance are described. Additional information is given on process selection to assist Water Undertakings in the appraisal of tenders for treatment plant.

Copies of the Report are available from FWR, price £35.00 less 20% to FWR Members