Water situation for Upper Ivel – July- August 2023
All data presented courtesy of the Environment Agency and Met Office (Crown copy right 2023)
Rainfall:
We had a particularly wet July, with 210% of Long-Term Average (LTA) in the Upper Bedford Ouse catchment. This was then followed by August which started wet but became increasingly dry as the month progressed. As the end of August sees the end of meteorological summer, the 3-month average (June- Aug 2023) for our catchment was 105% (normal) of LTA. The spring and summer combined can be considered as notably high, averaging 128% of the long- term average for our catchment area.
Soil Moisture Deficit (SMD)
The soil moisture deficits [SMD] by the end of August was 100+mm, and in the normal range for this time of year. Soil Moisture deficits for week ending 31 Aug 2023. Data based on weekly MORECS data for real land use and compared to an analysis of historic 1961 – 1990 LTA dataset.
Definitions:
Soil Moisture deficit (SMD) – The difference between the amount of water in the soil and the amount of water that the soil can hold (field capacity).
Ground Water (GW):
The groundwater levels across East Anglia’s western region continued to recede throughout the summer months as expected for this time of year but remain in the Normal range compared to historic levels.
Springs and River flows:
The main spring at Ivel Springs in Baldock started to flow on 14 th January 2023 but has ceased to flow as of 24 th June 2023, effective flowing for only 23 weeks in the year. This spring should flow year-round albeit at reduced flow levels in late summer / early autumn….Historically the mill at Blackhorse (closed in 1870s) would have milled wheat year-round for the people of Baldock and surrounding villages.
The second spring at the Ivel Springs nature reserve (upstream of culvert) in Baldock started to flow on 1 st January 2023. Surprisingly we have continued to see a minimal flow throughout July August, meaning we do have water along the whole Ivel form the head spring downward. This is important as it has allowed a slow recovery of flora and fauna in the upper reaches. Flow at Blackhorse mill started by the end of the first week in January 2023.Again we are pleased to report that there is still flow at Blackhorse mill at the end of August 2023.
The river Ivel flows are officially measured at Blunham. Heavy rain events in July saw increased flow which returned to normal during August (Green Zone).
Reservoir Stocks:
Water from the Ouse is transferred at Offord into Grafham Water reservoir. After twelve months of reduced capacity Grafham Water reservoir has finally returned to full capacity during June – Aug 2023 (94% -blue line on graph) which is in line with the normal operating level of 90%+.
End of June 2023 Grafham Water reservoir stock compared to the Normal operating Curve, Drought Curve and 1995-1996 stock levels.
Looking forward:
The Upper Bedford Ouse catchment has been in official “drought” from June 2022 until May 2023. The exceptional rain fall in March and continued aquifer recharge into mid-May 2023 has thankfully resulted in a change in status to “Recovering Drought. Despite the “summer” 3-month period with rainfall at 106% of the Long-Term Average the upper Bedford Ouse remains in “Recovering Drought.”
For the nine months period of drought experienced in 2022/ 2023 Affinity did not instigate any hosepipe bans instead they continued to pump water from the ground and allowed the river to dry all the way from Baldock to Radwell (acknowledged result of their Drought Plan).
Since 2019, RevIvel have been highlighting the plight of the chalk headwaters of the Ivel. Throughout this time Affinity Water have been making all the right noises, however more water has been taken from the aquifer than ever before!
Consequently, the river Ivel and its associated flora and fauna continues to suffer……..