Epa 625 6

FROM THE PREFACE Wastewater collection systems are dynamic, not static. There is no single maintenance method, equipment, or technique that works best. Keeping an open mind, trying new techniques and technologies benefits sewer system operators. No two collection systems are alike. Maintenance staffing, skill levels, equipment, budgets, age and complexity of the system make each agency unique. However, collection systems do have many traits and problems in common. Based on inventory and analysis, problems are identified. Defects may then be prioritized, and corrective maintenance operations put into effect. Preventive maintenance techniques can be applied to all collection systems. Preventive maintenance is cost-effective; it strives to prevent problems from occurring rather than reacting to difficult situations and "putting out fires." This book examines problems shared by all agencies: roots, grease, deterioration, hydraulic inefficiencies and structural defects. New solutions to age-old problems are applied: TV inspection and video interpretation, rehabilitation analysis and trenchless technologies. Computerized maintenance management and GIS softwares are discussed. Jetting, line cleaning and exciting developments in nozzle technology are included. Roots and chemical root control foam, wastewater control and grease are major topics as well. Wastewater Collection System Maintenance shares insights drawn from operator experience, trial and error, successes and failures in the field, interviews and years of research and studies. A user-friendly rating and evaluation system is explained and applied to field conditions. Equipment operation and maintenance, and "tricks of the trade" are also discussed. As cities grow, new systems are extended upstream from older sewers. Many of these core drainage basins are now under capacity and in need of capital improvement projects. There are approximately 600,000 miles of sanitary sewers in the country. Nationwide, there exists a huge backlog of sewer pipes that need rehabilitation. Replacement would cost many billions of dollars. Maintenance operators are entrusted with the care and feeding of an aging sewer infrastructure.

"This manual contains overview information on treatment technologies, installation practices, and past performance."--Introduction.