Interaction of Water Transport Pipelines with Their Surroundings and Third Party Activities

Waternet manages three large pre-stressed concrete water pipelines (PCP) laid in 1953 and 1964, with a total length of 210 km and diameters of 1500 and 1200 mm, which provide pre-treated water to industry and an infiltration area for drinking water production of Waternet. Yearly about 100 million m³ of water is transported through these pipelines. The pipeline routes pass a variety of landscapes with vital infrastructure (like railroads, highways, dykes), urban areas and agricultural use. Failure of the pipelines might impact the functioning of vital infrastructure and the safety of people. Also, third party activities around the pipeline route can lead to failure of the pipelines. Where the pipeline routes pass through farmland, natural subsidence causes several risks, like diminished soil cover. The interaction between WRK pipelines, surroundings and third party activities is a complex and ongoing matter, which requires continuous attention from the pipeline staff and operators. Waternet developed an extensive condition assessment program and monitoring program to manage the failure risk of the pipelines, as well as a combination of measures to deal with third party activities. However, to implement the measures program successfully, extra steps are needed. This paper explains how the pipelines and their surroundings `interact' and how Waternet is dealing with these interactions. It explains the analysis into the risks and shows how measures were developed.