For major water and wastewater municipalities standard corrosion control guidelines inform infrastructure investments. Standard practices, including voltage gradient and soil sample testing provide insight on site corrosivity. These measures inform mitigation efforts, producing numerous benefits which are projected to compound over time.
This paper looks at one major water and wastewater municipality with an established system for external corrosion control. Details of their systematic approach, how it developed and is applied, are included. The primary techniques the municipality uses are also discussed. A specific example of an application of impressed current retrofit on a ductile iron water main is explored.
Costs and benefits for implementing these measures are explored here. With attention to how awareness of corrosion impacts evaluation, design, and construction processes for municipalities. Life cycle asset costs are analyzed with a focus on systematic corrosion control measures. Costs discussed include simplified environmental and social factors. Providing a more complete view of the impact systematic corrosion control can have for a municipality.
Key words: External Corrosion Control Program, Water Infrastructure, Condition Assessment, Renewal Engineering, Cost Benefit Analysis, Polyethylene Encasement, Cathodic Protection Retrofit