|
3.2 Diffuse source discharges
Diffuse pollution is often difficult to attribute and many pressures remain unidentified.
Table 9 Diffuse pollution causing risk of failure in the Solway Tweed RBD
| Main Industrial Groups |
Diffuse Source Pollution |
| Agriculture, Forestry and Fishing |
148 |
| Energy and Water |
43 |
| Sewage and Refuse Disposal |
17 |
| Other |
10 |
| No identified |
3 |
| Manufacturing |
2 |
| Transport and Communications |
2 |
| Mining and Quarrying |
1 |
| Construction |
0 |
| Total |
226 |
Figure 6 Percentage of failure risk caused by diffuse Pollution in the Solway Tweed RBD
Figure 6 and table 9 above show the breakdown for all water bodies at risk from diffuse sources of pollution in the Solway Tweed RBD.
The agriculture, forestry and fishing sector is by far the largest contributor to diffuse pollution in the Solway Tweed RBD. Agricultural diffuse pollution is caused by run off and seepage of fertilisers, weed killers and slurry. It is often problematic to identify the source of such pollution directly. With forestry, the main source of diffuse pollution is through acidification, caused by run off of rain water that has taken up acids from the needles and leaves of trees.
The sewage sector can be responsible for contamination of water from leaks and seepage while, roads can also be a source of diffuse pollution as cumulative leakage from vehicles is washed into surface water and drains and subsequently discharged. Diffuse pollution from the construction industry on the other hand is almost entirely due to spillage.
Table 10 below provides further information on some of the main sectors, illustrating (where data is available) the contribution that the sector makes to the overall Solway Tweed economy, the value it places on water use (Scotland wide) and the volume of water that is used (Scotland wide).
This table provides a good example of the differences in use of water. For example, agriculture will use a (relatively) small quantity of water (for irrigation) at a vital time of year to add considerable value to a crop, however electricity generators will use vast amounts of water all year round with each m3 having a much lower value.
Table 10 Contribution to the Solway Tweed economy and value/volume of water use in sectors connected with diffuse pollution
| Diffuse Sector |
GVA 200137 |
Sub sector |
Value of use38 p/m3 |
Volume of use39 million m3/year |
Agriculture, Forestry
and Fishing |
£98.6m |
Agriculture |
23-138 irrigation benefits only |
56.5 |
| Energy and Water Supply |
Production and distance of electricity £71.8m |
Electricity generation |
0.00-0.8240 |
3,783 cooling |
| Sewage and refuse disposal |
Not available |
Sewage and refuse disposal |
n/a |
n/a |
| Manufacturing |
Food & Drink £360.1m |
Food Processing Including Whisky and soft drinks |
12.5 food
21 beverage |
260 |
| £192.8m |
Textiles |
4 |
1.8 |
| £5.6m |
Paper and Pulp |
16 |
87.7 |
| Transport/ Storage and Comms |
£262.3m |
Transport/ Storage and Comms |
n/a |
n/a |
|
