- How the valley in Linn Park was formed, where it rises, where it goes, why it floods, the new flood prevention works,
- The health of the river and how it is measured - bugs [viz invertebrates]
- What lives in and on the river is described elsewhere on the web site
- Fish - Wildlife
- River plants in and on the banks - Botany
- Birds and Animals that rely upon it - Wildlife
Linn Park has an amazing geological history, as has been recognised by many organiasations, least of the Linn Park Gentlemen's Walking Club: who else goes home with a piece of coal ?
The Geological Society of Glasgow comments:
Linn Park is one of Glasgow’s hidden gems – a deep rocky gorge and an impressive waterfall tucked away in the busy southside suburbs. The rocks tell a story of Glasgow’s long distant past, many millions of years ago, when volcanoes and tropical coal-swamps dominated the landscape. The gorge was carved through the tough rocks by the White Cart river (merely thousands of years ago!) when it was swollen by melt water from the Ice Age glaciers. Water and coal have since powered Glasgow’s industrial revolution and if you look carefully you can still find traces of it in the woods and river banks, slowly being reclaimed by Nature.
Another comment from the British Geological Survey in 2013 reads:
Along the picturesque river in Linn Park, sedimentary rocks of the Carboniferous age Limestone Coal Formation can be seen.
At Linn Waterfall, the sedimentary rocks have been intruded by a resistant microgabbro sill which forms the waterfall that gives the park its name. Hexagonal columns can be seen in the sill at the falls, similar to the columns at the Giant’s Causeway in Northern Ireland.
Downstream of the waterfall the river runs in a deep gorge. Landslips along the gorge walls indicate that the steep gorge is unstable but also produce good exposures of the sandstones and siltstones that were once deposited by ancient rivers - rock fall at Millholm.
The British Geological Survey Report for Glasgow has three reference points in Linn Park, namely
- Court Knowe [Ref Point: 17]
- The Waterfall [Ref Point: 9]
- White Cart Water, Holmwood House [Ref Point: 8]
An overview by Stuart Nisbet:
The landscape of the area has been shaped by the most recent glaciation which ended 12,000 years ago. The underlying rocks date from the Carboniferous age (310 – 350 Million years old). They have been exposed through the erosive power of the White Cart and its contributing burns. Some have also been exposed by man (by quarrying and mining).
In Linn Park and Netherton Braes, we can see rocks from three main stages of the Carboniferous period [oldest first]:
- Viséan (Lower Carboniferous), c.350 to 330 Ma. These occur later, when lavas were intruded into the local strata, notably forming Linn Waterfall.
- Namurian (Upper Carboniferous), c.330 and 310 Ma. Almost all of the rocks in the area are from this period (Limestone Coal Formation and Upper Limestone Formation).
- Westphalian (Upper Carboniferous to Early Permian), c.310 to 300 Million years ago. These outcrop in the valley of the Kittoch Water, at the upper end of Netherton Braes, near where the Kittoch meets the White Cart, opposite Overlee Park.
Within the Namurian period, the Index Limestone forms the boundary between the Limestone Coal Group and Upper Limestone Group. This limestone was formed from the shells of billions of marine creatures which settled out of a shallow sea. The shells of these creatures can still be found today, fossilised in the limestone. The Index limestone outcrops generally down the west side of the Cart, thus rocks to the west of the Cart are from the Upper Limestone Group and to the east, from the Limestone Coal Group.
Limestone Coal Formation
When the Limestone Coal Group was laid down, Britain lay much further to the south than today, approximately on the equator. The area which now comprises Central Scotland was part of a large tropical delta, similar to the Amazon delta today. Most of the time the area was flooded by the river and sediments were laid down which formed sandstones and shales.
Over long periods of time the level of the land gradually rose and fell in a cyclic fashion. When the land rose high enough in the estuary for plants to grow, tropical forests developed. The decay and subsequent burial of these forests resulted in the formation of the coal seams in this area.
Upper Limestone Formation
In the Upper Limestone Group, flooding by the sea was a more common event and limestones are more frequent than coals. The periods which formed these economic minerals were relatively infrequent events. Thus the limestones and coals represent only a small percentage of the strata in the area. The bulk of the rocks are sandstone and shale.
Catchment Areas etc
The river running through Linn park is one of two "Carts": the White Cart and the Black Cart. The rivers meet just before they join the Clyde to the North East of Glasgow Airport. The White Cart drains an area including the Eaglesham Moor. The Black Cart drains the flatter lands around Paisley and Johnstone: read more about them in these documents from SEPA, which describe the catchment areas, the likelihood of flooding, and the flood management plans:
- Black Cart: http://apps.sepa.org.uk/frmstrategies/pdf/pva/PVA_11_12_Full.pdf,
- White Cart: http://apps.sepa.org.uk/frmstrategies/pdf/pva/PVA_11_13_Full.pdf.
The rivers are distinctively different with the White Cart passing through Linn Park in a steep sided gorge formed presumambly in the Ice Age. And this is what makes Linn Park such an attractive place to visit. The steep fall on the river gives rise to lots of "White water"as it tumbles down - hence its name.
Water flow in the River
The flow of water in [or the gauging of] the river is monitored at the Weir just above the Bailey Bridge which provides access to the Gas Monitoring station. There is a path to it from the edge of the Cemetery - See Walking, and select the walk called: "White Bridge loop to the Netherton Braes".
The records from 1981 to 2017 are held by the National River Flow Archive, and can be viewed here: https://nrfa.ceh.ac.uk/data/station/meanflow/84030. One does ask why the records for 2018 have not yet been transferred.
The records for the last few days are available from the Scottish Environmental Protection Agency at http://apps.sepa.org.uk/waterlevels/default.aspx?sd=t&lc=133118. It is these records that are then transferred to the National River Flow Archive.
There are two other gauging stations above this one, both on tributaries, namely
Health of the River
The Clyde River Foundation [CRIMP] is one of the best sources of information whether it be research or history.
The Field Studies Council [FSC] provide the basic tool of how to identify wildlife in general. Their specific publication entitled "A key to the major groups of British freshwater invertebrates" is part of their AIDGAP series and is used by CRIMP.
Possibly one of the best publications is River Clyde Fishery Management Plan 2009-15 [pdf format]
Obviously a healthy landscape improves the health of the river. One good site is https://www.buglife.org.uk/ whcih had a project in Glasgow. The report is here: https://www.buglife.org.uk/sites/default/files/Glasgow%20Buzzing%20final%20report_0.pdf. Again it is a report on invertebrates.
How do we judge the River ?
First of all we look at the color of the water: there seem to be three main colors:
- A good peaty color - nice and clear when the water flow is relatively low.
- A horrible dirty color - just after a down pour after a dry period. All the muck off roads and pavements, as well as direct drainage off the land. All the dog shit gets and stuff washed away thank heavens. It also includes all the microscopic bites of rubber from car tyres as the wear away, as well as dust from brake pads - which includes asbestos ....
- A good muddy color - after a period of prolonged rain - just natural erosion. Does a lot of good, and when the water recedes, the banks and islands in the river a refreshed.
Next we look at the river life:
- Do we see all the normal guys - Ducks, Kingfishers, Dippers, Wagtails, and the Herons - and do we see them regularly ?
- Are the fish rising ?
- In season do we see fish leaping the waterfall - both Salmon and Brown Trout.
- And in the spring do we see shoals of smalts ?
Conclusions [as at summer 2019]
- Fish are happy. Salmon haven't been seen recently [a problem in all rivers in Scotland]
- Ducks are now rare - the hundreds of 20 years ago are down to just a few
- Other river birds are simply not seen as often as they used to be - when did we last see a Cormorant ?
How do we judge the the Park and environs ?
- First of we look at the way the park is maintained.
- Tarmac roads and paths - no drainage means run off straight into the river.
- Metalled paths, i.e the zigzag and the top wood.
- Soft paths - their misuse leads to damage
- Grasslands - over mowing has now ceased
- Woodlands - not maintained
- River banks - not maintained
- Next we see what types of bird are prevalent - are we overdosed with gulls and magpies ?
- Are the usual small birds still arround - what's the dawn chorus like ?
- Do we see bats down by the river, and in the hedgerows ?
- Lastly we ask are we seeing squirrels, rabbits, deer and and foxes etc
Conclusions [as at summer 2019]
- [under discussion]