Dartmoor CAM

This walk: 2010-3-17. Burrator quarry, granite road posts, Drake's Leat/Plymouth Leat, oak tree, Burrator Dam, hazel catkins, commemorative plaques, suspension bridge anchor points, Longstone Manor, windstrew, cider press, keeves, explosives store/WWII shelter, growan, quarry interface between Devonian Period rocks (370 million years old) and Dartmoor granite (Permian Period, 280 million years old), gorse flowers.

A walk following a similar route was done on 18 March 2009 - see that for some details, better weather and a joke from our guide on that day!

Walk details below - Information about the route etc.

Granite road posts lining the road past Burrator quarry. Note the old rusting iron rings that once held iron chains.

Looking along Drake's Leat towards Burrator Dam.

A Plymouth Corporation Water Works water catchment area boundary stone, 1917 AD.


Between 1591 and 1898		fresh water from the River Meavy

flowed for 17 miles along	Drake's Leat		to Plymouth

Slate plaques seen around the end of a short stone wall beside the leat.

An old oak tree growing on the bank above the River Meavy, below Burrator Dam.

Dartmoor CAM movie

Moor Strollers gathered beside Drake's Leat for a fairy tale lecture about the local history. Sir Francis Drake riding his white horse ahead of the water running into Plymouth, indeed! It is recorded, however ..... it must be a Dartmoor tale!

Click the photo to download

File size: 2 MB.
Time to downlaod: e.g. 13 secs
Length 18 secs

Looking along the leat towards Burrator Dam.

Burrator Dam - in the mist.

1985 commemorative plaque to mark the 400th anniversary of the Act of Parliament authorising the building of Drake's Leat to bring water to Plymouth.

Hazel catkins - its Springtime!

Plaque to commemorate the enlargement of the dam during 1923-1928.
Transcription .....

Borough of Plymouth 1923-1928 Burrator Reservoir This stone commemorates the enlargement of the reservoir from a capacity of 668 to 1026 million gallons. Alderman RW WinnicottJP Mayor Chairman of the Water Committee
F Howarth	Councillor JE Fillar Vice Chairman	RJ Fittal

Plaque to commemorate the opening of Burrator Dam in 1898.
Transcription .....

Borough of Plymouth Burrator Reservoir
Commenced 1892 James Manserch Edward Sandeman Engineers	Completed 1898 JT Bond Mayor and Chairman of the Water Committee 1891-1898

Plaque marking that 110 feet below is the foundation stone of the dam (1895), seen halfway across the dam.
Transcription .....

Plymouth Corporation Water Works Burrator Reservoir 110 feet beneath lies the foundation stone of this embankment which was laid on the 2nd / 24th day of July 1893 ???
????????? OP ??? Bond Chairman of the Water Committee	James Manserch Edward Sandeman Engineers

One of the anchors for the suspension bridge that carried a road to Sheepstor village during the building of the original dam .....

..... and another anchor point.

Looking to the end of the pier on the south side of the reservoir beneath the old suspension bridge.

An old chain lays discarded.

A view of the dam on this misty day.

The two suspension bridge anchor points seen on the return from the pier.

An old anchor point - believed once featured in Concrete Monthly?

..... in more detail - seen better on the previous walk linked at the top of this page.

A view along the path - the Rhododendrons have been cut back.

The following six photographs were taken by Hugh .....

Notice at Longstone Manor.

Misty view of Longstone Manor.

The windstrew at Longstone Manor. A threshing job for the ladies of the manor.

Cider Press and keeves at Longstone Manor.

This photo has attracted comment. The building is believed to have been constructed (1) during the building of the dam to house explosives or (2) as a shelter during WWII, either in the event of the dam being attacked or to shelter LDV (Local Defence Volunteers) personnel during bad weather. There are four of these buildings in the area: (i) almost opposite the toilets at Burrator dam, (ii) over the stile and to the right at the Sheepstor end of Burrator dam, (iii) near the Sheepstor end of the earth dam and (iv) in the grounds of Burrator Lodge, in the cliff at the back. In line with being explosive stores, they have concrete doors and non-sparking gunmetal / bronze / non-ferrous metal (?) hinges. They have ventilation shafts in the roof. This caption will be amended should further information be found.

An example of "growan" - granite decomposing by natural processes. Location: see the red flag on the map below.

Seen in Burrator Quarry car park: I remember 40 years ago (1970 et seq.) that there was a large plaque attached to this rock face saying what it was. From Devon County Council's "Geology in Devon" online publication: Quote - "The Upper Burrator Quarry offers an opportunity to view a rare exposure of the contact between the Dartmoor granite and Devonian rocks. Indeed, veins of pink granite can be seen penetrating these rocks which were once slates resulting from the deep burial and intense deformation of mudstone originally laid down in marine conditions. However, the high temperatures that resulted from the intrusion of the hot granite transformed them into recrystallised rocks known as hornfels. Minerals such as black tourmaline have been formed in the original slate." Dartmoor granite is about 280 million years old, (= Late Paleozoic Era, Permian-Carboniferous Period) the Devonian rocks are about 370 million years old (= same era, Devonian Period).

Addendum: Another reference (from DNPA) has been given to me that states: "This site features rare exposures of the contact between the Permo-Carboniferous Dartmoor Granite and Devonian country rocks of the Kate Brook Formation. The contact is highly irregular and shows evidence of mobilisation of the metasediments and segregation of felsic and mafic constituents. The contact country rocks have been thermally metamorphosed to form hornfels with extensive tourmalinisation."

The area is a SSSI - Site of Special Scientific Interest.

A close-up of the interface between the granite and the Devonian rocks, with the Devonian on the left.

More hazel catkins.

Common gorse .....

..... and its flowers, wet with the mist .....

..... and flowers outlined in condensed mist droplets.

Walk details

MAP: red route out and blue route back. Note the red marker flag indicating the position of the growan quarry - being a dump of material from the excavation for the foundations of the nearby earth dam that are bedded about 32 metres down, going down some 30 metres through growan and then another 2 metres into solid granite.

The walk was accessed very easily via the road from Yelverton and Dousland, with parking at the P symbol near the bottom of the map below the Quarry (dis) markings near the Dam.

Statistics
Distance - 5.4 km / 3.3 miles (approx, as it was on 18 March 2009).