Water |
Water is essential. In Brighton all our clean drinking water is held in a remarkable layer of rock beneath our feet called an aquifer, a key reason why the Council brought our downland into public ownership.
Summary
Brighton and Hove Council acquired the Downlands for the explicit purpose of protecting the city’s water supply. The Brighton Downs Alliance believe this must remain a key feature in Downland policy, crucially as climate change increases the vulnerability of the aquifer. The UK government currently define the South East as an ‘area of serious water stress.' The aim should be to safeguard and increase the resilience of, the aquifer below the Downland through a better understanding of the underground water systems and substantive changes to land-use regulations.
Brighton and Hove Council acquired the Downlands for the explicit purpose of protecting the city’s water supply. The Brighton Downs Alliance believe this must remain a key feature in Downland policy, crucially as climate change increases the vulnerability of the aquifer. The UK government currently define the South East as an ‘area of serious water stress.' The aim should be to safeguard and increase the resilience of, the aquifer below the Downland through a better understanding of the underground water systems and substantive changes to land-use regulations.
Background
The chalk hills act as a sponge, rapidly absorbing and filtering rainwater, making our spring water the purest there is. There are no surface rivers between the River Adur in the west and the River Ouse in the east, apart from a few chalk streams at the edges chalk outcrop, but there are numerous underground rivers, streams, watercourses, culverts, adits, sewers and storm drains hidden beneath our feet. The exact locations of so many of these are currently unknown.
Our aquifers are the most polluted across the whole of the South Downs, mostly by nitrates from fertilizers leaching into groundwater. Seven out of thirteen boreholes have nitrate-levels that exceed drinking water standards. To ensure that the water supply has low enough contamination, Southern Water mix various sources. Another result is that Southern Water have spent tens of millions of pounds over the last two decades on nitrate and phosphate stripping plants to make it fit for us to drink. (The tenant farmers pay high rents to the council, meaning they use high yielding practices – i.e. substantial use of fertilizer – but these rents do not offset this massive ‘clean-up’ operation cost.) This highlights the urgent need for restorative farming practices to become the norm on the Downland Estate and a central objective of the Whole Estate Plan.
With the lack of awareness of groundwater protection, we need a comprehensive, holistic approach to the particular challenges posed by contamination of our water supplies. For this to happen in earnest, we need a thorough mapping exercise to pool information to determine what lies beneath. First, there needs to be an audit of our existing pipework. Adits are horizontal tunnels designed to carry water. We require an adit audit - to discover and map the locations of the 12km of adits linking water pumping stations across Brighton. Then, a multidisciplinary approach to look at the Hydrology, Geology, Archaeology, Mycology and Ecology of our area will enable us to work with nature to serve our aquifer.
There are signs of hope for the protection of our aquifer with excellent projects like The Aquifer Partnership (TAP). However, projects like these need funds now to implement the essential remedial works identified. Tackling polluted water must be a high priority in order to ensure our fresh water is clean for generations to come.
The chalk hills act as a sponge, rapidly absorbing and filtering rainwater, making our spring water the purest there is. There are no surface rivers between the River Adur in the west and the River Ouse in the east, apart from a few chalk streams at the edges chalk outcrop, but there are numerous underground rivers, streams, watercourses, culverts, adits, sewers and storm drains hidden beneath our feet. The exact locations of so many of these are currently unknown.
Our aquifers are the most polluted across the whole of the South Downs, mostly by nitrates from fertilizers leaching into groundwater. Seven out of thirteen boreholes have nitrate-levels that exceed drinking water standards. To ensure that the water supply has low enough contamination, Southern Water mix various sources. Another result is that Southern Water have spent tens of millions of pounds over the last two decades on nitrate and phosphate stripping plants to make it fit for us to drink. (The tenant farmers pay high rents to the council, meaning they use high yielding practices – i.e. substantial use of fertilizer – but these rents do not offset this massive ‘clean-up’ operation cost.) This highlights the urgent need for restorative farming practices to become the norm on the Downland Estate and a central objective of the Whole Estate Plan.
With the lack of awareness of groundwater protection, we need a comprehensive, holistic approach to the particular challenges posed by contamination of our water supplies. For this to happen in earnest, we need a thorough mapping exercise to pool information to determine what lies beneath. First, there needs to be an audit of our existing pipework. Adits are horizontal tunnels designed to carry water. We require an adit audit - to discover and map the locations of the 12km of adits linking water pumping stations across Brighton. Then, a multidisciplinary approach to look at the Hydrology, Geology, Archaeology, Mycology and Ecology of our area will enable us to work with nature to serve our aquifer.
There are signs of hope for the protection of our aquifer with excellent projects like The Aquifer Partnership (TAP). However, projects like these need funds now to implement the essential remedial works identified. Tackling polluted water must be a high priority in order to ensure our fresh water is clean for generations to come.
Actions
The actions below are essential to achieve Brighton and Hove City Council pledges on the climate, ecological and health emergencies, without which Brighton and Hove City Council will fail in its duty to current and future citizens.
The actions below are essential to achieve Brighton and Hove City Council pledges on the climate, ecological and health emergencies, without which Brighton and Hove City Council will fail in its duty to current and future citizens.
- Multidisciplinary project mapping the underground water systems, crucially including adits;
- Reduction of nitrate allowance for the Brighton Downs Estate to sustainable levels;
- Formalising restorative farming practices into Downland policy.
Resources:
There is substantial evidence that the health and vulnerability of the Brighton and Hove aquifer is of great concen. The changing atmospheric conditions due to climate change, with more significant periods of drought and an overall increase in precipitation, have adverse effects on the water quality in the aquifer. With progressive regulation and industry leading land management policies the effects of climate change on the Brighton and Hove aquifer can be offset.
Climate change and aquifers:
“Studies of soil processes suggest climate change is likely to lead to increased nitrate leaching from the soil.”
– Stuart, Gooddy, Bloomfield and Williams, 2011
British Geological Survey (2020) The impact of climate change on nitrate concentration in groundwater
IPCC (2008) Linking climate change and water resources: impacts and responses
Brighton and Hove water supply:
Current government guidelines for Nitratre Vulnerable Zones.
Southern Water (2019) Our Drought Plan
Furthermore, in 2003 Southern Water commented that:
'For a number of years the nitrate concentration in the raw water has been rising due to agricultural practices. The concentration of nitrate also shows an annual cycle, with peaks during the winter months as the aquifer is recharged by rainfall. The combination of the general rise in nitrate concentrations and the annual cycle is such that there is a probability that the drinking water standard of 50 mg/l for nitrate will be exceeded during winter months.'
There is substantial evidence that the health and vulnerability of the Brighton and Hove aquifer is of great concen. The changing atmospheric conditions due to climate change, with more significant periods of drought and an overall increase in precipitation, have adverse effects on the water quality in the aquifer. With progressive regulation and industry leading land management policies the effects of climate change on the Brighton and Hove aquifer can be offset.
Climate change and aquifers:
“Studies of soil processes suggest climate change is likely to lead to increased nitrate leaching from the soil.”
– Stuart, Gooddy, Bloomfield and Williams, 2011
British Geological Survey (2020) The impact of climate change on nitrate concentration in groundwater
- A brief account of how climate change is going to result in greater input of nitrates into aquifers.
IPCC (2008) Linking climate change and water resources: impacts and responses
- This paper highlights the different upcoming problems that climate change poses to water security at a global scale.
Brighton and Hove water supply:
Current government guidelines for Nitratre Vulnerable Zones.
Southern Water (2019) Our Drought Plan
- Plans by Southern Water to cope with greater drought periods. Note this report fails to engage with environmental/pollution concerns and takes a curious ‘we’ll look into it once a drought happens approach’.
Furthermore, in 2003 Southern Water commented that:
'For a number of years the nitrate concentration in the raw water has been rising due to agricultural practices. The concentration of nitrate also shows an annual cycle, with peaks during the winter months as the aquifer is recharged by rainfall. The combination of the general rise in nitrate concentrations and the annual cycle is such that there is a probability that the drinking water standard of 50 mg/l for nitrate will be exceeded during winter months.'