Hafren Water in conjunction with quarry operators, nature conservation organisations and regulatory authorities has recently completed research projects in 2007 (MA/5/2/005) and 2008 (MA/6/2/013) on water-based quarry restoration.
Floating Wetlands: Assessment of viability as a method for the restoration of wet mineral workings (2008)
Water-based quarry restoration – methodologies, technologies and approaches (2007)
Topics included ground and surface water control and the design of water-dependent target habitats, including the hydro-ecology of fens and mires. An assessment of sustainable development opportunities including open loop heat pumps, wind turbines, hydroelectric generation and CO2 emission reduction has been undertaken using RETScreen software (www.retscreen.net) has been completed. Various quarry edge treatments and bird strike issues are examined. A literature review of floating wetlands and limited field trials were undertaken to assess the viability of floating wetlands for quarry restoration.
Sub-watertable mineral extraction has been undertaken for hundreds of years resulting in the creation of large areas of wetland and numerous waterbodies. Many of these have significant ecological and public amenity benefit, such as the Norfolk Broads, and are important resources at regional and national levels. Historically the majority of restoration was generally passive and unplanned. However increasing public awareness, greater understanding of the water environment and progressive tightening of planning regulations and European Union (EU) directives have placed a greater emphasis on the optimisation of water-based restoration design. This is appropriate given the long-term effects of restoration compared with the relatively short operational life of a quarry and the proven potential for schemes to make a major beneficial contribution to the surrounding area.
The creation of waterbodies can have significant consequences for the
local environment which may include, amongst others, effects upon: ecology
(including BAP species), flood management, regional water resources,
river baseflow, public amenity value and perception, bird-strike and the
local landscape. These issues are generally considered in isolation,
or on a site-specific basis, however it is considered that a more holistic
and structured approach to the assessment of variables associated with
water-based restoration would be extremely beneficial. This would
also promote integrated groundwater and surface water management in accordance
with the EU Water Framework Directive legislation and greater consideration
of ecology in accordance with the EU Habitats Directive.
The research was funded under the Mineral Industry Sustainable Technology Programme (MIST). MIST was established by the Mineral Industry Research Organisation (MIRO, www.miro.co.uk) in mid-2002 under the terms of reference of the Aggregate Levy Sustainability Fund (ALSF). The objective of MIST is to 'reduce the environmental effects of mineral extraction through the development, promotion and implementation of sustainable technologies'. Copiesof these and other research reports are available from the MIST website (www.mist.org.uk).
Hafren Water are part of the Hyporheic Network (see www.hyporheic.net)
