Aging Water Infrastructure (AWI) Research
To determine the condition of water systems, data is collected through observation, direct inspection, and indirect monitoring. The data tells us how the pipes are structurally and operationally. The data helps show the causes of failures. In turn, we develop ways to prevent future breakdowns.
EPA sewer system condition assessment has focused on the reduction of Infiltration and Inflow (I&I). Infiltration is groundwater seeping in through cracks. Inflow is surface water flowing in. Excessive I&I can cause sewers to back up or overflow. It can also overload sewage treatment plants, resulting in water not being treated correctly. The weakening of a wastewater collection system can affect ecosystems and water availability.
A common challenge for wastewater utilities is corrosion of the collection infrastructure, specifically, concrete surfaces, mortar, and metal reinforcement material. EPA works to identify the types of pipe corrosion, the extent, the locations, and the best.
US EPA. (2007). "Aging Water Infrastructure Research: Condition Assessment of Collection Systems." (PDF) (2 pp, 334 KB) Publication No. EPA/600/F-07/014.
The most common defect for all types of pipe is leakage through the pipe wall, joints, or connections. This can allow water to leak out or contaminants to leak in. Leaks can lead to soil erosion or the pipe not to operate effectively.
EPA is looking at conditional assessment approaches that are non-disruptive. For example, they don't require excavation, water shut offs, or entry into the pipeline. Non-disruptive technologies provide not only economic and customer convenience benefits, but they also reduce the risk of dislodging sediments or biofilm already in the system.
EPA is looking at remote monitoring and wireless technologies for pipe inspections. EPA is working on standardizing technical guidelines, data requirements and indicators for condition assessment and inspection.