Extraction by quarrying and mining requires careful control of the resulting water discharge to guard against flood risk and environmental damage.
In order to manage the water levels within its district, the IDB (Internal Drainage Board) may require rifes and drains to be installed, which can then cause delays to extraction processes as these will need to be progressively diverted in order to continue the mining or quarrying process.
A large UK operator was experiencing such a problem with a quarry, which had a series of IDB rifes and drains within the quarry extraction boundary. These watercourses, which are linked, often carry high flows, so it is important that re-routed watercourses have the same capacity to avoid potential flooding issues for the site and neighbouring areas. Envireau Water provided calculations to show that the re-routing was sound using survey data and flow simulations, enabling the operator to gain IDB approval to their proposals and therefore continue extraction without interruption.