Transactions of the American Society of Civil Engineers, Vol. Lxxii, June, 1911

The Washington filtration plant has already been fully described.[2] At the time that paper was written (November, 1906), the filtration plant had been in operation for only about 1 year. It has now been in continuous operation for 5 years, and many data on the cost, efficiency, and methods of operation, have accumulated in the various records and books which have been kept. It is thought that a brief review of the results, and a summary of the records in tabular form, will be of interest to the