|
North of Scotland water quality 1999 – 2002
Summary report
Rivers
| Year |
A1
km |
A2
km |
B
km |
C
km |
D
km |
Unclassified
km |
Total
km |
| 1999 |
N/A |
N/A |
477.6 |
153.3 |
29.0 |
N/A |
11404.2 |
| 2000* |
960.9 |
1645.8 |
385.7 |
138.0 |
14.6 |
8259.3 |
11404.2 |
| 2001 |
1421.0 |
1560.9 |
384.6 |
85.9 |
21.8 |
7950.3 |
11424.6 |
| 2002 |
2019.6 |
3482.8 |
658.4 |
86.1 |
13.2 |
5143.7 |
11403.8 |
* Figures changed from those previously reported
due to inclusion of toxic substances classification.
A1 = excellent
A2 = good
B = fair
C = poor
D = seriously polluted
U = unclassified
Main points
The main stems of many of the largest
rivers in the area have maintained their ‘good’ quality classification, or
better. The substantial river quality improvements recorded 1999-2001 have
been maintained, with a smaller overall improvement recorded in 2002. Some
stretches have improved, but most of these have fluctuated in class for
several years.
On the positive side, the Gillock Burn near Thurso,
Linkwood Burn near Elgin and Diney Burn South of Aberdeen all recorded
improvement, but 5km of the Murkle Burn, near Thurso deteriorated from A2
in 2000 to B in 2001 and now C in 2002. There are no classification
records for this stretch before 2000. Investigations as to the causes of
the downgrading are ongoing.
The main change in river classification has been
the first-time assessment of nearly 3000km of ‘new’ rivers. The north of
Scotland contains nearly half of Scotland’s rivers (in terms of length),
many in remote areas, and carrying out a complete classification is a
major task. The unclassified stretches are generally believed to be of
good quality, but may be subject to unrecorded local pressures. SEPA hopes
that remaining significant stretches will be classified by 2006.
Estuaries
| Year |
A
km2 |
B
km2 |
C
km2 |
D
km2 |
Total
km2 |
| 1999 |
235.9 |
26.3 |
4.8 |
0.0 |
267.0 |
| 2000 |
253.1 |
10.9 |
2.9 |
0.0 |
266.9 |
| 2001 |
255.6 |
8.4 |
2.9 |
0.0 |
266.9 |
| 2002 |
257.93 |
6.14 |
2.85 |
0.0 |
266.9 |
A = excellent
B = good
C = unsatisfactory
D = seriously polluted
Main points
The generally high quality of estuarine
waters in the north of Scotland has been maintained.
Cromarty Firth, near Invergordon
The area near the harbour and the pier that served
the former Alcan aluminium smelters improved from class B to class A,
because of reductions in tributyl tin (TBT) levels, which are a legacy of
activity there.
Inverness Firth, near Allanfearn
This area improved from class B to class A,
following improvements to the sewage works that serves Inverness.
Ythan estuary
Nutrient enrichment from farming in the catchment
causes excessive algal growth in the estuary. The whole catchment is
designated as a ‘nitrate vulnerable zone’ with a programme of action to
reduce the amount of fertiliser released into the environment. However, it
will take several years for there to be any evidence of improvement.
Aberdeen, River Dee estuary
Minor oil spills in the harbour are responsible for
this area remaining class C. An action plan is scheduled for 2003 – 2004
to deliver improvements.
Coastal water
| Year |
A
km |
B
km |
C
km |
D
km |
Total
km |
| 1999 |
8137.6 |
225.7 |
120.2 |
19.1 |
8502.6 |
| 2000 |
8178.0 |
206.9 |
104.6 |
13.6 |
8503.1 |
| 2001 |
8190.3 |
204.0 |
93.1 |
16.0 |
8503.8 |
| 2002 |
8208.7 |
194.6 |
84.2 |
14.5 |
8502.0 |
A = excellent
B = good
C = unsatisfactory
D = seriously polluted
Main points
Generally, there have been many
improvements in sewage treatment, and these should help ensure we achieve
the 2006 quality targets throughout the North of Scotland. In particular,
most of the major PFI schemes serving the main population centres from
Inverness to Aberdeen have now been completed.
Loch Portree
2km has improved from class C to class B, following the connection of an
unsatisfactory sewage discharge to the main sewer system.
Thurso Bay
2.3km upgraded from class C to class B.
Dunnet Bay (Castlehill)
3.2km of class C has improved to class B, due to improvements in sewage
treatment. SEPA staff also inspected local farms and recommended minor
improvements to reduce their environmental impact.
Wick harbour
The harbour has improved from class C to class B because there are fewer
oil spills and less rubbish.
Fraserburgh
1.5km improved from class D to class B because 12 untreated sewage
discharges have been removed and a new high performance treatment plant is
in operation.
Lossiemouth
1km improved from class C to class B after RAF Lossiemouth installed oil
interceptors and Scottish Water upgraded the Coulardbank surface water
sewer.
Johnshaven
2km improved from class C to class B following the provision of sewage
screens.
Western Isles
Three short stretches (Ashdail Cottages, Bayhead and Leverburgh) have been
downgraded to class C following the observation of sewage debris on the
shore. Another short stretch in West Loch Tarbert was downgraded to class
C because of large quantities of litter.
Loch Leven, Lochaber
24km of the loch remains class C due to elevated levels of polyaromatic
hydrocarbons (PAHs) in sediments.
Peterhead Lido
In 2002 0.3km was downgraded from class B to class C because it failed
bathing water standards. This was probably a one-off event caused by a
sewage pumping station malfunction. The station has been refurbished and
the results from this year’s monitoring show a return to previous years’
excellent standards. |