The impact of urban groundwater upon surface water - eTheses ...

STUDY SETTING
But under the General Quality Assessment (Environment Agency, 1998) the Tame is still
categorised within the worst classes E/F (poor/bad) with severe impacts reported on the river
ecology. Rapid urban run-off from precipitation events can generate high surface water flows
and large pollutant loads that add to the hostile conditions for aquatic life.
The long history of industrialisation and urbanisation has left a legacy of contaminated land,
which has caused significant inorganic and more recently organic contamination of the
underlying groundwater. The contribution of sewage effluent and industrial pipe end
discharges to the surface water quality and flow are relatively well understood but little is
known about the contribution of groundwater across the study reach.
3.2 Land use
Heavy industry and housing grew up side by side with little or no legislation to control
contamination of soils, groundwater and surface water.
Studies of urban groundwater pollution throughout the UK (Lerner et al.,1996) and in nearby
Wolverhampton (Bridge et al., 1997) identified associations between particular contaminants
and land use. Sampling of the Birmingham Aquifer has identified groundwater contamination
including heavy metals and chlorinated solvents associated with industrial land use (Rivett et
al., 1990, Ford et al.,1994). Metal working and related industries which constitute 59% of the
industry overlying the Birmingham Aquifer (Rivett et al., 1990.) are thought to be among the
most significant polluters.
A high concentration of industry is located in the Tame Valley which is particularly
vulnerable to groundwater pollution owing to the limited thickness of the drift and the shallow
water table. Recent studies (Thomas, 2001) of land use on the unconfined Birmingham
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