The Ivel springs rise on the northern edge of Baldock and the river flows in a northwest direction towards the villages of Norton, and Radwell.
In 1901, Baldock was a small rural market town with a population of two thousand and fifty-seven people. The economy relied on the brewing industry and agriculture. The water supply for the Baldock townsfolk was primarily via local wells.
The Parishes of Letchworth and Norton were sparsely populated with less than 200 people living on the land purchased by the First Garden City in 1903.
Water abstraction to supply a growing population
The first borehole was sunk in 1904 to serve Letchworth Garden City.
Water supply to Baldock via the borehole commenced in 1906.
By 1935, six boreholes had been sunk with capacity to supply 220,000 gallon/hr (or 1.0ML/hr). At this time the combined population of LGC and Baldock was approximately 18,000.
The population of LGC and Baldock continued to grow up to 1961 (32,275 people). Between 1935 and 1961, the population increased by 80%. It is reasonable to assume that water consumption also increased by 80% over this time frame.
The First Garden City Ltd managed the water supply until 1960 when The Lee Valley Water Company was formed as of 1 April 1960.
The current valid abstraction license was established in 1966 (dated Aug 1966) 6/33/14/*G/0010 (incorporating Baldock Road, Letchworth, Bowring, Letchworth and Fuller, Letchworth).
The current licence authorises abstraction of 5,391,675 cubic metres per year (maximum of 20.46 Ml in any 24 hour and a daily average of 14.77 Ml/d (over 365 days).
Population Growth Throughout the Twentieth Century:
Letchworth Garden City
Letchworth Garden City was established in 1903 when the village of Letchworth, and land from the parishes of Norton and Willian were purchased by the First Garden City Ltd.
Letchworth Garden City was designed with a maximum population of thirty-two thousand in mind. The town grew steadily with the model population reached in 1991 and by 2019 the population had further increased, estimated to be just over thirty-four thousand (34,000).
The population of Baldock started to grow in the 1930’s with further development in the 1950’s. Significant population increase occurred in the mid 1980’s with the development of Clothall Common estate. The current population is estimated to be ten thousand, six hundred and twenty-four (10,624).
Current Map of Letchworth, Baldock and Surrounding Area 2021.
Future Population Growth Anticipated with the NHDC Local plan 2011-2031:
The combined population of LGC and Baldock in 2019 was just under 45,000 people.
The Local Plan has provision for an increase for 2167 houses in Letchworth Garden City up to 2031. In Baldock there are significant expansion plans with up to 3298 extra houses planned. Since there are currently 4500 residential units catering for 10,624 people today in Baldock, it is reasonable to assume a similar population density and house occupancy for the future in the towns of LGC and Baldock. Thus, we can assume a population increase in the order of 12,500, bringing the combined population to 57,680 by 2031.
Water consumption per capita has increased considerably over time. In the 1860’s and before mains water supplies then water consumption per person was approx 36 l/day. By the 1960s, this had increased to 85l/day. In recent decades water consumption has increased considerably, driven primarily by an increase in the use of showers, baths, and increased use of household appliances such as dishwashers and washing machines.
Supplying water to this ever-increasing population and preserving water flow in the upper reaches of this precious chalk river is a major challenge. Current water consumption in the UK is 149l/day for a single person household. Affinity Water supply area is consistently one of the worst in terms of consumption per person with 2016/7 water consumption at 152/day.
Affinity Water currently abstract on average 14.77 ML/day from the Baldock Road, Bowring and Fuller boreholes (6/33/14/*G/0010) and in many months of the year exceed this level to serve a current population of 45,000 people in LGC and Baldock.
By 2031, when the population exceeds 57,500 people, alternative water sources must be found.
NIAB Cambridge monthly rainfall (mm) over 30 years-
Over the thirty year period ( 1991-2020) we see seasonal variation but no overall reduction in rainfall in autumn and winter “recharge months”.
So we can confidently say the lack of water in the River Ivel is down to OVER ABSTRACTION.
Affinity Water Abstraction is Detrimental to the River Ivel.
Abstraction licence was granted on 21st Aug 1966 (Great Ouse River Authority).
In the 1990’s abstraction in the range 8-10 million litres per day.In early 2000’s this increased to 12 Million Litres/Day.
Abstraction increased even further from 2008 onwards to the maximum licensed level.
Baldock Road, Bowring and Fuller 6/33/14/*G/0010 currently authorises 5,391,675 cubic metres per year
Affinity Water operates this licence close to full licensed quantities in normal years i.e. maximum of 20.46 Ml in any 24 hour period and an average of 14.77 Ml/d.
However, in drought or dry conditions the level of the groundwater table reduces their ability to abstract!
2005-2007 and 2011-2012 are examples of years when Affinity Water were forced to reduce abstraction because there was insufficient water!
River Ivel at Iron Bridge, Radwell – Summer 1983 when water abstraction was approx 8-10 Million litres/day.
Could we see this coming? – Yes!
NIAB Cambridge monthly rainfall (mm) 2016-2020
Three winters with low recharge (autumn 2016- spring 2019) and unabated abstraction directly lead to the catastrophic event in summer 2018 – Nov 2019 when up to 2.5km of the River Ivel ran dry and DIED.
Affinity Water Data – Surface Water Flow monitoring- 2.5Km stretch of Ivel from source clearly under severe “stress”from June 2018 onwards……only recovering in Dec 2019.
Surface water flow fluctuates according to the GroundWater variation denoting a classic Chalk river
The perennial spring head at Ivel springs to Radwell Lodge was dry from August 2018 until November 2019.
All this under the management of Affinity Water and under the nose of The Environment Agency.
Zero flow at Black Horse Mill Aug 2019.
“Dead” Chalk River at Radwell (2.5 km from source in River Ivel) in September 2019
If the Environment Agency model shows the catchment to be “below average” in a year when they allow a chalk river to dry up for 2.5 km from its spring source, then the model clearly fails to reflect the reality on the upper Ivel.
The EA should aim to manage a resilient and sustainable chalk aquifer to ensure year-round flow of the River Ivel.
The headwaters of the River Ivel have been under severe stress for decades.
Status of Spring flow – Nov 2021
Despite a high level of winter recharge in autumn/ winter 2020/21 the perennial spring head (spring 1) in the Ivel Spring nature reserve has been dry from August 2021 – Nov 2021.
Flow is still seen at spring 2 (Spring Drain).
Affinity Water data – up to Sept 2021
Upper reaches of the River Ivel at risk from Over-Abstraction
OS Map (1899-1913)