Precast SuDS components, such as concrete pipes, chambers and precast attenuation tank systems, are manufactured to Design Chemical DC-4 class with an intended working life exceeding 100 years. This is a minimum life expectancy all SuDS should meet as the systems need to perform effectively over the lifetime of the development or housing estate it serves.
One of the main characteristics that make precast SuDS last longer than other alternatives is the fact that concrete gets stronger over time. This may not be applicable for a range of other proprietary SuDS alternatives made of polypropylene which tend to lose stiffness and strength over time.
Design
One of the main elements behind the proven service life is the robustness of the structural design of precast attenuation tanks and pipeline systems. Concrete pipeline systems in the UK are manufactured to the tried and tested BS 9295 with no compromise over elements such as lateral forces or acceleration & braking loads. Other concrete attenuation tanks are designed to Eurocodes structural standards. The main alternative lightweight attenuation tank system should be designed to CIRIA’s C737. But it is not clear if all brands in the market are certified to C737.
Maintenance
Ease of maintenance is another element which can make precast SuDS and attenuation tanks last longer than other alternatives. Precast SuDS are usually fully accessible and any sediment which makes it inside a precast attenuation SuDS can be removed.
During maintenance, precast SuDS can take significant water jetting pressure reaching up to 4,000 psi, removing any FOG or sediment from the attenuation system. This is compared to 2,600 psi only for most virgin plastic pipes (as suggested by the Manual of Drain & Sewer Cleaning).
Find out more about the service life of concrete pipeline systems and why it is believed to exceed 100 years here.
