In 2022 RevIvel met Anglian Water, Affinity Water, Water Resources East and the Environment Agency to discuss John Lawson’s proposal to fix the Ivel. It was agreed that a 2-stage feasibility study would be done to see if John’s idea could work.
The first stage was to update the Environment Agency’s groundwater model to include new data and refine it to better reflect actual river conditions. Consultants WSP were employed to do this and have made good progress despite running a little behind schedule. At a meeting on 23rd May their lead consultant fed back their initial findings.
Key findings to date are:
1) The old version of the EA groundwater model was based on poor data from limited and inappropriate monitoring points.
2) Since 2015 Affinity Water has put in better monitoring points which are actually in the upper Ivel catchment.
3) Using this better data WSP has refined the model to more accurately reflect what we know has been going on in the river. It is “work in progress” and further tweaks need to be made.
4) The improved model suggests that the old version was significantly underestimating the amount of water in the river! Note RevIvel has always argued this based on historical evidence (mills/watercress beds).
5) It also suggests that reducing abstraction at the boreholes will result in significant amounts of water appearing in the river as flow, even under drought conditions.This is very good news
6) John Lawson will review the work done by WSP on behalf of RevIvel.
7) The model has only been run with data up to 2020 but will be updated with 2021-2023 data later this year. Funding for this has been agreed by the EA. Inclusion of this data is likely to further increase accuracy.
These initial findings are very positive but come with the caveat that the work has yet to be verified by the Environment Agency so keep the champagne on ice for now.
The second phase of the project is to extend the modelling further downstream to test various abstraction reduction scenarios in and around Baldock, assess how much flow will make it into the Great Ouse for potential abstraction into Grafham Water, and investigate the viability of using the replenished chalk aquifer as storage of emergency water which could be released in the event of exceptional drought.
In the meantime, Affinity Water have sunk a new borehole for the proposed augmentation scheme in the compound at Ivel Springs where the Anglian Water sewage pumping station.They have agreed to share pump test data with us but at the time of writing we have yet to receive it. Further testing and commissioning work is due to take place later this year and RevIvel will ask to be involved at every stage.