All data presented courtesy of the Environment Agency and Met Office (Crown copy right
2022)
Rainfall:
During November the pattern of Atlantic frontal systems continued with high rainfall events from fronts passing over
on the 2 nd , 6 th , 15-16 th , 19 th , 24 th and 26 th Nov. The Bedford Ouse catchment of which Ivel is a part, recorded
catchment- average rainfall in excess of 100mm, equivalent to about 200 percent of the long-term average (LTA).
Monthly rainfall totals for the past 12 months as a percentage of the 1961-1990 LTA
However, there is long way to go to make up for the lack of rain throughout 2022.The blue line tracking well below
the expected annual rainfall of 600mm (LTA).
Soil Moisture Deficit (SMD)
The soil moisture conditions showed a significant wetting through the month. The Met Office MORECS grid squares
covering the Ivel improved to 10-20mm SMD by the end of the month indicting that the soils are nearly at field
capacity. Recharge of the chalk aquifer is now likely in response to further rainfall events.
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).
Field Capacity (FC)-The amount of water the soil can hold is generally called field capacity which is the amount of
water that remains after gravitational forces have drained water from the soil.
Ground Water (GW):
With the soil moisture deficit now in the region 10-20mm SMD we can expect the start of recharge of the chalk
aquifer in the hills around Baldock, North Herts.
Looking at a regional picture across the East Anglian chalk, GW levels remain at Below Normal / Normal levels
compared to historic November levels.
Springs and River flows:
The main spring and second spring at the Ivel Springs nature reserve in Baldock remain DRY.
The main spring stopped at the end April 2022 (having flowed for only 8 weeks) and the 2 nd spring stopped by end
June 2022.
There are no springs flowing at Norton.
Changes during November see 2 additional springs flowing in Radwell Meadows.
Any current standing water in the riverbed at the iron bridge and Norton (upstream of the Radwell meadow springs)
is the result of A1/M road / hard surface runoff.
Standing water in the Ivel springs reserve is a result of rain events and surface water run off from Baldock town.
The river remains very low through Radwell but starting to recover from Stotfold onwards.
Reservoir Stocks:
Water from the Ouse is transferred at Offord into Grafham Water.
Recovery of reservoir stocks in Grafham Water is slow with the reservoir currently being currently only 64% full (blue
line on graph) (Notably Low).
Looking forward:
October and November have been wet but we need to see this pattern continue throughout December 2022- March
2023.
We need at least 120% of normal throughout the winter for the groundwater to recover and there to be any hope
of seeing the upper Ivel flow in 2023!
Sadly, we could see this coming because the 2021 winter rainfall was low resulting in limited recharge of the chalk
aquifer by springtime 2022.
RevIvel was warning Affinity Water of this and asking them to reduce abstraction way back in April 2022 (when the
Ivel 1st spring dried up!).
Affinity Water continued to abstract as much as they could within legal limits and physical capability during 2022.
Affinity Water principally rely on ground water (GW) with some provision from Grafham Water reservoir and did not
apply a Temporary Use Ban (hose pipe ban) in 2022 despite GW and rainfall being notably low in our catchment in
the summer.
The EA advised Affinity Water to reduce abstraction. The advice was ignored, and abstraction continued albeit
limited to 10 Ml /day due to physical constraints.
It is not clear why they behaved as they did.
Hoping for winter water is surely not a strategic plan.
Unless we get a wet winter, we can expect 2023 will be a challenging year for the Upper Ivel………..