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Ruralrunoffattenuation
intheBelfordcatchment
C
ontext
Belford Burn catchment is located close to the eastern coast of the United Kingdom, in Northumberland. The catchment
area upstream of Belford village is 5.7km². It is a generally
rural area,
at an altitude of between 50-200m AOD, with
predominantly
pasture and cultivated grasslands
, and some mixed forest. In the catchment, average annual rainfall is
around 700mm, with an average annual standard percentage runoff of 40% (but often much higher during storm events).
M
anagement
issues
Belford village has a long history of
flooding
, with historic damage to properties and infrastructure (roads and rail), and
approx. 35 homes being identified as at risk from flooding.An Environment Agency flood defence pre-feasibility study concluded
that
traditional flooddefenceswerenot suitable
for Belford because of the high cost, lack of space for flood walls and
banks, and the small number of properties at risk, resulting in an unfavourable cost-benefit assessment. There was a desire
to deliver an alternative catchment-based and more cost-effective solution to the problem.
In addition to the flood risk concerns, the river waterbodyWater Framework Directive (WFD)
ecological status
for Belford
Burn in 2009 (i.e. early in implementation) was classed as
poor
, and predicted to remain as such by 2015. Average annual
reactive P concentrations exceeded levels prescribed under the WFD. Other water quality determinands (Ammonia, DO and
nitrates) were below recommended thresholds. Main sources of water pollution identified were agricultural diffuse pollution
and domestic septic tanks. Potential water quality risks could also affect Lindisfarne National Nature Reserve and Special
Protection Area (300 species of birds) which is located at the downstream end of the catchment.
Management issues therefore include
three types of pressures:
flood pressures (a combination of natural exceedance and
alterations to land use and drainage upstream),WFD pressures (changes in water quality status due to agricultural diffuse pol-
lution within the catchment) and Birds Directive pressures (also relating to poor water quality being transferred downstream).
NWRM IMPLEMENTED
•
N1: Basins and ponds
•
F10: Coarse woody debris
•
F13: Peak flow control structures in managed forests
•
F14: Overland flow areas in peatland forests
© Environment Agency
Offline storage pond constructed of a leaky timber barrier,
to release flow slowly to the river
