Assessing the impact of renewal scenarios on the global structural state of sewer pipe networks

The first objective of this paper is to demonstrate how mathematical models simulating the structural state of sewer pipes can help to assess the financial resources required for the preservation of sewer networks. The second objective is to assess and compare the annual replacement rate that should be applied to four different Canadian sewer networks to stabilize their global structural state for the long term. The required annual replacement rates are similar for the four studied networks, even if their global structural states were different prior to replacement. Results also show that the required annual replacement rate is three times less if the deterioration states of all pipes in the network are known, as opposed to the case where the structural states are unknown. This demonstrates the importance of sewer pipe inspection for the planning of sewer pipe renewal.