FR0369

Mar 1993

I BENEFITS

This work will enable a better understanding of the use of cement mortar linings for corrosion protection of iron water mains. Durability studies will assist rehabilitation planning decisions and evaluation of water and effluent disposal problems will assist users in meeting regulatory requirements. Development and appraisal of laboratory test rigs for assessing performance of cement mortar linings will enable recommendations for a suitable type test, for inclusion in an appropriate standard or specification.

The objective of this programme of work is to provide guidance on the use of cement mortar linings in relation to their durability, effect on water quality and disposal of associated effluents. The objective of this report is to identify progress and major issues encountered during the second year of the project.

The use of draft guidelines (Appendix A) has assisted in the alleviation of effluent disposal problems associated with cement mortar lining of small diameter water mains. The use of laboratory rigs has proved unreliable for assessment of long term water quality effects of cement mortar linings. Durability studies have shown that degradation of cement linings occurs in soft water areas. Additional field sites and samples must be identified for satisfactory completion of water quality and durability studies.

Existing guidelines (17) should be followed when using cement mortar lined pipes, including the draft guidelines (Appendix A) which cover effluent disposal procedures for small diameter pipes. It is recommended that studies are continued into the development of laboratory based testing of cement linings, because such tests will be required for incorporation into appropriate standards/specifications.

V RESUME OF CONTENTS

Progress in the investigation into the durability and environmental impact of cement mortar lining is reported. Problems and requirements are identified and effluent disposal guidelines are presented.

Copies of the Report are available from FWR, price £15.00 less 20% to FWR Members