PROJECT TOPSOIL SANDLINGS – MANAGED AQUIFER RECHARGE AND WATER QUALITY IMPROVEMENTS.
In Suffolk we are carrying out a project to address the levels of water available in groundwater aquifers and how we can improve the quality of water stored in natural underground reservoirs. See link in Google Maps
We are grateful to the Suffolk Coasts and Heaths Area of Outstanding Natural Beauty and the Environment Agency for their support. This project is being run in parallel to the East Suffolk Catchments Partnership project which brings together farmers, water companies, local authorities and business.
This project is within the Sandlings area of Suffolk where soil conditions makes growing fruit and vegetables popular. The soils are very good growing medium for these types of crops but the downside to the sandy soils is that they do not retain water, nutrients and pesticides for very long. As anyone who has ever poured water onto the beach will know it quickly filters through the soil and in the Sandlings fills up the aquifers (groundwater) underneath. Due to these factors water is a very important resource for farmers in this area and availability during drier periods is difficult, especially as East Anglia is a very dry part of the UK.
Crops being grown in the Sandlings area
Reservoirs for agriculture
Many farmers rely on abstraction from rivers and groundwater. During long periods of low rainfall agricultural needs add to the public water supply and environmental needs putting pressure any water that is available. To ensure they have a ready supply many farmers choose to construct on-farm reservoirs that collect water during wetter periods (generally autumn and winter) which they can then use to irrigate their land during drier periods. This is a sensible approach, however, reservoir construction takes land out of production and are not usually designed with wildlife habitats in mind. This results in areas of land offering very little benefit other than creating a water source for irrigation.
Putting water back into underground aquifers
The Topsoil project in this area aims to trial a different method of water storage. Pilot areas will be selected to trial recharging the aquifer (groundwater) by abstracting water from a local water course and allowing it to infiltrate through the soil into the aquifer below. The hope is that the majority of the water added to the aquifer will remain in situ and then this can be abstracted to be used to irrigate crops in drier period. This will free up land that may be turned into reservoirs and also reduce pressure of abstraction from water courses in dry periods
Water quality and land management change
We will also be looking to address water quality issues both in the groundwater and surface water (rivers and ditches). The aim for this part of the project is to work with farmers to trial different land management techniques including;
changes in the crops grown;
different crop rotations;
use of cover crops;
changes in ploughing practices;
changes in applications of pesticides and nutrients;
managing land runoff and changes to ditch management
Top (l-r): 1. Crop rotation; 2. Cover crops, which can help reduce runoff into water courses and help maintain organic matter in the soil (reducing the need for nitrates and phosphates); 3. Constructing an earth bund in a ditch to slow the water flow so sediment can drop out
Bottom (l-r): 1. Attenuation ponds are ways of managing land runoff/drainage to improve water quality in rivers; 2 & 3. silt traps hold sediment and prevent it entering rivers and ditches.
Filtering out impurities
We would also like to trial ways of filtering the abstracted water before it enters the groundwater to see if this improves the water quality. This would include using unimproved grassland or woodlands as the infiltration point or to install a layer of woodchips for the water to filter through before entering the aquifer.
Water could be filtered through areas of grassland or woodland that are unmanaged and free of added nutrients or pesticide, or possibly through layers of wood chippings that would help to filter out any pollutants within the abstracted water
If successful, aquifer recharge could be a method used by other farmers in the local area, with land that has suitable geology, to store water without taking land out of production and reducing the need to abstract water from water courses when water levels are lower.
Flooding and better farming
Storage of water within aquifers could have a small impact on reducing river flooding but if cumulative across a large enough area this impact will increase. We would also like to see an improvement in water quality in the areas where land management changes take place with no detrimental effects on yields and profits for the farmers involved. We can then share this information with other farmers to show methods that will help reduce their impact on the water environment.
We will keep you updated on our progress throughout the project. Click here to sign up to our email alerts.
Funding for Topsoil
Topsoil is a collaborative project involving partners throughout Northern Europe from Germany, Denmark, Holland, Belgium and of course the UK. The partnership is looking at various ways to protect the ‘topsoil’ that is vitally important in providing crops for food, biofuel and animal feed, water for drinking and the environment.
Essex and Suffolk Rivers Trust have secured a budget of €220,000 of funding from the European Union (Interreg) as a partner in a three-year project called Topsoil. This means we will receive up to 50% of this total as long as we can find the other 50% from funders in the UK.
We are grateful to our supporters Suffolk Coasts and Heaths AONB and Environment Agency for valuable matched funding.
If you or your organisation wishes to support this project, or any of our other work, then please contact us. We urgently need to secure funding for years 2 and 3 of Topsoil so please do get in touch.