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BMP measure 1 (exclusion of stock from watercourses) was readily understood and
appreciated from the aspect of reducing the risk of diffuse pollution so long as an
alternative reliable water supply was able to be installed.
BMP measure 2 (buffer strips) were also acceptable in most circumstances, but with
varying tolerance of the amount of land take involved. The theory is understood, but
not always will the ideal width of buffer strip be allowed on all farms.
BMP measure 3 (stock removal from wetlands) will not be applicable on all farms,
but within the catchment area where other BMPs were installed three wetland areas
were identified for exclusion from stock access. There are other wetlands in other
parts of the catchment that are still open to stock. Farmers are aware that grazing
value is low, but are also concerned that these areas will have to be managed in a
different way to become a wildlife habitat and to prevent the growth of unsightly or
invasive vegetation.
Measure 4 (farm ponds) was by far the most difficult measure that SAC promoted
within the catchment. Farmers are environmentally aware but some could not see
the need for farm ponds to treat lightly contaminated water. Farmers want alternative
systems to treat ‘dirty water’, but under current regulations ponds would not be
permitted to treat such water. The amount of land (and number of ponds) required
to treat such water to an acceptable discharge quality could be very large. However,
advantage can be taken of existing wetlands by isolating them from livestock.
BMP measure 5 (removal of shallow crossings over watercourses) will involve either
land take or involve a considerable amount of engineering to deepen the watercourse
and avoid the land take.
Measure 6 (removal of short lengths of ditch by piping) will have been carried out
on farms for different reasons, such as making parts of fields more accessible for
silage making. Farmers will generally be willing to adopt this measure as an aid to
production. However, this activity should not be used extensively as it contravenes
SEPA’s position on avoiding new culverts.
Fundamental to BMP measure 7 is to provide water from a natural source. This makes
the supply sustainable and should, in theory, result in no change in the amount of
water being taken from the watercourses. Apart from minor maintenance it has
a nil ongoing cost, unlike a metered water supply. An important consideration in
designing such a BMP is the level of abstraction given the regulations flowing from
the Water Environment and Water Services (Scotland) Act 2003.
WATER QUALITY ANALYSIS
Low Flows
Mean concentrations of faecal indicator compliance parameters under dry weather
conditions, are generally low. There is a slight elevation in their concentrations during
low flows in the summer bathing season. However, the low flow fluxes represent a
very small proportion of the total flux in the bathing season and seem not to impact
on compliance with Directive 76/160/EEC (Wyer et al., 1997)
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