The Keadby pumping station appraisal was carried out to manage flood risk in the Isle of Axholme and protect thousands of homes, businesses, roads and other key sites. Due to the high cost implications that flooding would bring, a detailed project appraisal was necessary. As a result, approximately 100 simulations were to be run. Time pressures and model complexity led Capita to use Jacobs’ Flood Cloud service to save time, improve model calibration and optimise decision-making.
Software run with Flood Cloud: Flood Modeller and TUFLOW
Time to run 100 simulations with normal approach: 1,680 hours
Time to run 100 simulations with Flood Cloud: 48 hours
Time saved using Flood Cloud: 97% (68 days)
High performance computers cost: £0
Extra licence costs: £0
Additional labour costs: £0
Keadby Pumping Station is the outfall for the River Torne within the Isle of Axholme to the Tidal River Trent. It comprises six gravity sluices which maintains water levels within the Isle of Axholme and discharges fluvial flow to the Trent when tide levels permit. High flows are pumped via six pumps, providing approximately 32 cu.m/s discharge capacity when required.
Continuing to manage flood risk in the Isle of Axholme is vitally important. Ending water management activities could result in extensive flooding to many thousands of homes and businesses, over 30,000ha of high-grade agricultural land, internationally important conservations sites and major critical infrastructure. A total of 15,761 residential properties, 921 businesses and 3 major road networks were at risk and the economic assessment has valued the area at £5.2billion over 100 years.
The detailed project appraisal for short term and long term continued operation of the pumping station (gravity and pumped discharge) included hydraulic modelling and a full economic assessment for each of the proposed options.
Hydraulic modelling and the use of Flood Cloud
The hydraulic model for the River Torne / Isle of Axholme was created using Flood Modeller’s 1D solver and TUFLOW’s 2D solver. The dependency of the low-lying land setting makes for a complex network of pumping stations (19 in total). The terminal assisted outfalls are complex systems combining pumping stations, gravitational culverts and outfalls which work in response to the tidal levels on the River Trent to help push through high flow when gravity is low.
With the full economic appraisal requiring analysis of five return periods with five climate change scenarios for each, and multiple option scenarios for the pumping station, a total of 30 model runs per option was needed. This equated to approximately 100 runs in total. Using the local Flood Modeller licences available to the Capita modelling team, models could be run in 2 iterations of 50 model runs which would have taken approximately 70 days of processing time and would have a subsequent impact on other Capita projects requiring access to the licenses.
Using Flood Cloud enabled Capita to run approximately 100 simulations in 2 days instead of 70. The time saving enabled the modellers to build more precise models with better and more accurate calibration. They were able to model and run more options which led to better decision-making to choose the preferred option.