Quarry Dewatering

Dewatering is often undertaken at quarries to allow mineral to be extracted economically and safely.  Since January 2018 the Water Act (2003) now requires quarry operators to apply for an abstraction licence when dewatering.

A licence to abstract more than 20 cubic metres per day of water from one source and transfer it to another without intervening use, is called a Transfer Licence.  It is this abstraction licence that quarry operators who are intending on dewatering their site will need.

The need for this is in addition to any existing full abstraction licences, where more than 20 cubic metres of water are abstracted and used on site, for example for mineral processing or dust suppression.  An Environmental Permit for discharge of excess water to ground or a local watercourse will also still be required.  

Water resources are under increasing pressures from abstraction.  It is the role of the Regulator (Environment Agency (EA) Natural Resources Wales (NRW) and the Scottish  Environmental Protection Agency (SEPA)) to ensure that these finite resources are shared equitably between environmental/ecological needs and those of abstractors. Therefore, if the total volume of water being abstracted from a particular source is not known, it cannot be fairly managed. 

The window for sites currently dewatering to apply for a Transfer Licence under transitional arrangements will close on 31st December 2019.  The EA are suggesting outstanding applications are submitted by 1st October 2019.  It is therefore imperative that operators ACT NOW.

Following December 2019 the three year determination period will commence.  

Operators that have applied for a Transfer Licence can continue to dewater at the rate included o their application form until such time as their application is determined.  However, sites that continue to dewater without a Transfer Licence (or having submitted an application) after 31st December 2019 will be considered unlawful.

It is assumed that existing operators have a neutral impact on the environment and other water abstractors.  Therefore it is only necessary to demonstrate that the volumes applied for have been used at some point over the preceding 7 years (January 2010 to December 2017) and show how this water is moved around the site.  

Evidence of volumes abstracted may take the form of flow monitoring records, pump run time logs, invoices for pumping equipment, photographs of infrastructure, receipts/contracts.  
A schematic drawing is also required to show how water is transferred around the site and/or used on-site prior to excess water being discharged.

New sites or areas that were granted planning Permission after December 2017 will need a new Transfer Licence and are not covered by the transitional arrangements agreed between the Government and industry.  The main difference to the application process is the need to consider in detail impacts on the environment and other water users.

It will still be necessary to justify the volume of dewatering for which a licence application is being made.  This is likely to take the form of calculations based on known mineral permeabilities and saturated thickness.  A simple schematic diagram showing how water will be used and transferred across the site will also still be required.

The availability of groundwater within the catchment will need to be determined.  In the first instance this will take the form of determining the Water Framework Directive (WFD) quantity status and the prevailing attitude of the Regulator to abstraction, as set out in England in the EA Catchment Abstraction Management Strategy (CAMS).  If either the WFD quality status is ‘poor’ or the CAMS state that groundwater is ‘unavailable’ for abstraction a licence MAY NOT be granted unless mitigation can be provided.

An assessment will also be required of potential adverse impacts on other local water abstractors (derogation of water supplies) and impacts to water sensitive ecological sites.

Unless the environmental impacts of dewatering have been considered in a recent Environmental Impact Assessment (EIA) or ROMP, it is likely that the application will need to be supported by a detailed water features survey and an assessment of impact, in similar detail to that needed for an EIA.

For some sites rainwater makes up a large proportion of the water that needs to be pumped from the quarry void.  Such sites tend to be in low permeability deposits such as clays/ mudstones and some hard rock deposits.  These sites may not need to apply for a Transfer Licence.  However, an assessment will need to be undertaken by the operator to determine if:

• the dewatering is ‘wholly or mainly rainwater’ – no application required;


• it is uncertain if dewatering is ‘mainly’ groundwater or ‘mainly’ rainwater – further data collection and assessment will be necessary to determine if a water abstraction licence is needed or not;


• the dewatering is ‘wholly or mainly’ groundwater – application for a Transfer Licence is required.

The Mineral Products Association (MPA) has been working on behalf of its members to steer and simplify the transitional process and that for new sites. As a member of the Water Group of the MPA Hafren Water has been part of this process. We have also delivered presentations to Regional Groups of the MPA to help operators prepare for the application process and held discussions with leaders in the EA who are leading the licensing process.

We have completed a large number of wide-ranging applications for both small and large operators for both transitional and new Transfer Licences.  This has identified a number of unanticipated hurdles with the application process.

Through this involvement we are very aware of the potential difficulties with applying for either new or transitional Transfer Licences and our experience has highlighted the fact that no two quarries are the same and careful, thorough preparation and liaison with the regulators /NRW is key to a smooth application process.

An extension to the transitional application period beyond 31st December 2019 will not be permitted.  We therefore strongly recommend that you submit your application at the earliest opportunity before the transitional application period closes on 31st December 2019.