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2021-8-25. Most photos taken on a recon walk from 23rd June 2020, during covid. Venford Reservoir, dam, PUDC /RD-H catchment area boundary stones, overflow area, subsurface coarse bubble aeration upwellings, Water Works, commemorative stones, South Bench Tor, English Stonecrop, Rowbrook Farm & Jan Coo, Rowbrook House, River Dart, Middle Bench Tor, North Bench Tor, White Wood, Pipe Track, oak coppice, charcoal burning, foxgloves, Workman's Bridge and Ford, Venford longhouse, River Swincombe inlet, triple mortar stone, mention of Venford Brook flooded tin mill. D365-O14, (P13), P14.

Walk details below - Information about the route etc.

Previous walks in this area: 11 Feb. 2008, 9 Dec. 2009, 26 May 2010, 17 Aug. 2011, 16 Oct. 2013  

Reconnaissance walks: 15 June 2020, 23 June 2020,  6 Aug.2021 10 Aug. 2021

Google Satellite map + GPS track of the walk

 

 

Devon & Dartmoor  Historic Environment links Location
Venford Reservoir, Holne Holne
Weir at Venford Reservoir Holne
Longhouse south-west of Venford Reservoir, Holne Holne
Medieval buildings south-west of Venford Reservoir, Holne Holne
Deserted farmstead south-west of Venford Reservoir, Holne Holne
Tin mill in the Parish of Holne Holne
Tin mill in the Parish of Holne Holne

 

Venford Reservoir was built between 1901 and 1907 to supply water initially to Paignton but now Brixham, Ashburton and Widecombe-in-the-Moor receive water from here - see commemorative tablets pictured below. The land was bought from Richard Dawson, Lord of Holne Manor. The catchment area bought was 700 acres and is ringed by granite pillars marked "PUDC" on one side and "RD-H" on the reverse, signifying Paignton Urban District Council / Richard Dawson, Holne. There are 52 PUDC Boundary stones. The area of the lake is 33 acres. There were some renovations in 2009. Water is supplied by the Venford Brook and other local streams that feed into the reservoir but water is also piped from the Swincombe valley to feed in via pipe near the gate on the west side of the of the lake.  

Devon & Dartmoor HER - MDV115706 - Venford Reservoir, Holne

 

A view along the dam from the west end, near the car park. The stone pillar is one of the granite boundary stones around the catchment area of the reservoir marked "PUDC / RD-H", signifying Paignton Urban District Council / Richard Dawson, Holne - lord of the manor when the stones were erected. There are 52 PUDC Boundary stones (on the Dartefacts web site), this one being Number 1, facing the camera is RD/H, PUDC can be found behind it. 

 

The walkers at Venford Reservoir car park after the walk, eighteen of us - still smiling!

 

Just around the corner of the near-end of the parapet, on the road-side, (2nd row of stones up from the road surface, 3rd stone along the road from the end of the parapet), at SX 68604 71210, is a benchmark - a horizontal line with a "government arrow" below. The marks were made  by the Ordnance Survey during surveying for the Principal Triangulation of Great Britain (1783-1851), when benchmarks were used. The Retriangulation of Great Britain (1935-1962), when permanent markers e.g. triangulation pillars came into use.

 

Sign located across the road from the above viewpoint.  

  

The reservoir overflow area features a labyrinth weir which is designed to convey large flows of water by increasing the effective length of the weir crest with respect to the channel breadth. It leads into a spillway that bypasses the dam in time of excess water leading to a buried culvert that bypasses the water treatment works and returns excess water to Venford Brook, below the dam. A water engineering paper, Improving Dam Safety: Auxiliary Spillway Design, gives a good overview of the 2007-2009 safety improvements to Venford Dam.

The disturbance in the water towards the middle of the lake is where air is piped under the water to aerate it - this is the process of increasing or maintaining the oxygen saturation of water in both natural and artificial environments. Google Earth shows ten of these aeration points.  Aeration techniques are commonly used in pond, lake, and reservoir management to address low oxygen levels or algal blooms. Wikipedia - subsurface coarse bubble aeration. Aeration at Venford is generated at the treatment works by two large air compessors.

 

Another photograph showing a higher water level and the floating boom that is designed to catch floating debris.

 

Looking up the lake ..... It is fed by Venford Brook and an inlet from the River Swincombe. This flooded area was known to William Crossing as "Wennaford Bottom" and the lake as Paignton Reservoir- in the Guide to Dartmoor, Southern and Western Section, Southern Dartnoor, Ashburton District, Holne, p.40 (actually p.188 of 376, a new edition in five parts, in the time of Arthur Edmund Spender's Mayoralty of Plymouth,  which was 1908-1909).  Crossing's famous "Guide" was published as a complete edition in 1914.

 

Looking over the parapet at the Water Works below the dam; the main buildings house the filtration beds and show the chimneys on the old watchman's dwelling, Venford House, at the far end of the site. This is now a private house. 

 

First commemorative stone .....  

 

Top of the "draw-off tower" - photograph taken from the car park end of the dam of the draw-off valves ..... the left-hand yellow label says "Draw off valve No 4" ..... Draw off valves and tower images ..... the valves control water flow into pipes taking untreated water from the reservoir to the treatment works before it is distributed as potable water - the pipes can draw water from different levels in the reservoir .....

 

Take-off valve controls. The commemorative tablet above is to the right when looking at these devices .....

 

Another view. 

 

Another look over the parapet away from the lake shows three? water pipes (and two wall parapets) leading to the treatment works .....

 

The four pipes seen again from the far end of the dam, also the downstream face of the dam - not much to see here. 

 

The other commemorative stone, to the left of the "valves".

 

Google Earth (c) 2020 aerial view of the dam.

 

View from above the east end of the dam looking north-east, up towards South Bench Tor, or South Benjy Tor, which is labelled Benchator on the 1839 Holne Tithe Map; near the top of the map, below the "I" in Parish of W"I"decombe. Note the "Pot water to Collings Stoke" label on the tithe map, and "West Stoke" on the 1888-1913 25-inch OS map.

  

Looking left of north at the pointed Sharp Tor (1.6 km/1 mile) distant, Corndon Tor to the right and Yar Tor towards the left (both at 2.85 km/1.8 miles). The house to the left is Rowbrook, the house in the centre is Rowbrook House. 

 

Sharp Tor, SX 686 729, elevation 380 metres (1246 feet).

 

Rowbrook House ..... 

 

Rowbrook, or Rowbrook Farm, is an ancient farmstead with a medieval longhouse still standing. This was the home of the farm Apprentice, Jan Coo, who was called away by the pixies on three occasions. Other people at the farm also heard the calling of the pixies. He did not return from the third calling of his name and was presumed taken by the pixies or lost in the River Dart below. 

Devon & Dartmoor HER - MDV29851 - Former longhouse at Rowbrook Farm  

 

South Bench Tor, SX 691 716 .....

 

English Stonecrop, Sedum anglicum .....

 

As previous photograph.

 

View north from South Bench Tor .....

 

View across the top of South Bench Tor looking at the area that once had a triangulation pillar. Dartefacts web site: Site of ex-Trig Point on Bench Tor, SX 69160 71628 - see OS 25-inch map England and Wales 1841-1952.

  

View north-east from South Bench Tor to the Double River Dart (East and West Dart Rivers meet upstream at Dartmeet) .....

 

 Zoomed view of the River Dart. 

 

Google Earth image(c) 2002:  Bronze Age strip fields on the hill opposite i.e. west of South Bench Tor ..... the present image on Google Earth (2020) is not so clear, possible because of bracken growth in the summer months .....

 

As previous image but in more detail.

 

View to North Benchtor ..... with Middle Bench Tor in between .....

  

Looking north, approaching Middle Bench Tor, at SX 69120 71793 .....

   

North Bench Tor, SX 690 719, elevation 312 m (1,023 feet) .....

 

Closer view .....

 

Looking back, south, at Middle Bench Tor from near North Bench Tor.  

 

 

  

North Bench Tor .....

 

Cleft in North Bench Tor ..... 

North Bench Tor, north end rocks .....

High spot between North and South Bench Tors, i.e. Middle Bench Tor.

 

Looking back at the reservoir from North Bench Tor.

 

Path running north-west down from North Bench Tor into White Wood.

  

The "Pipe Track" - this is a well built, kerbed and banked track which follows the route of a pipeline from the reservoir around the promontory below Bench Tor, on a ledge above the River Dart. It continues and climbs again towards the Stoke Farm enclosures.

 

This is an oakwood that was once used for charcoal burning - the trees were probably coppiced i.e. cut back to stumps, known as stools, and left so that many long thin "trunks" grow up suitable for regular cropping. The traditional method in Britain used a clamp. This is essentially a pile of wooden logs (e.g. seasoned oak) leaning in a circle against a chimney. The chimney consists of 4 wooden stakes held up by some rope. The logs are completely covered with soil and straw allowing no air to enter. It must be lit by introducing some burning fuel into the chimney; the logs burn very slowly and transform into charcoal in a period of 5 days' burning. (Wikipedia - charcoal).

 

There are several ancient clearings , now overgrown, where the ground was levelled to make places for "burning" charcoal, known as "charcoal platforms" (video on Youtube). Here, they tend to be half-moon shaped on a steep slope. Charcoal was an important fuel in the Medieval times particularly where coal was not available, no doubt for blacksmiths' forges. It is essentially carbonised wood burns much hotter than wood minus its water, especially when assisted by forced airflow from bellows.

 

June - foxglove season .....

 

Digitalis purpurea, the foxglove.

 

The woods also provided a steady supply of bark for tanning. The Hamlyns Mill was situated in Buckfastleigh, being a woollen mill, and next door to it today in Mardle House is the Devonia Sheepskins and Tannery - a video of their processes can be seen HERE. Newton Abbot was a thriving Medieval wool town and associated with the woollen industry was the leather business. Hides left after the fellmongering process were made into leather. Tanners, boot and shoemakers, glovers and saddlers were all in business in Newton Abbot. As with the wool industry, business flourished over 600 years until after the Second World War. Nearby Bovey Tracy and Ashburton wre also involved in the wool trade and that usually involves skins and tanning to make leather which was widely used in the past. An impression of the tanning process may be seen on the web site of the Woodland Tannery, an modern enterprise combining tanning and foretry.

 

At this point the track has left the wood and proceeds along the Pipe Track above Venford Brook .....

 

Looking back at the wood .....

 

If the track is followed for its full length, it reaches a gate at the back of the Water Works. It looks as if the track out of the Works has not been used lately! It is then necessary to retrace a few yards and climb the bank, ending up following the fence to the corner of the enclosed land .....

 

One of the granite stones around the catchment area of the reservoir marked PUDC / RD-H’ boundary stones, signifying Paignton Urban District Council / Richard Dawson, Holne - lord of the manor when the stones were erected. There are 52 PUDC Boundary stones (on the Dartefacts web site), this one being Number 50.  

  

PUDC / RD-H’ boundary stones, Number 49 on the Dartefacts web site.

 

Signs at the gateway into the Water Works at the east end of the dam.

 

View along the dam, showing the overflow area. There are two PUDC/RD stones either side of the road at the bend that is seen at the top of the hill - Waterworks Hill.

 

The overflow structure.

 

The dam was completed in 1907 to supply local towns.
Holding around 900 million litres of water, this 13-
hectare reservoir provides water for Widecombe-in-the-
Moor and Ashburton as well as making a valuable
contribution towards Brixham and Paignton's needs.

The water comes from Holne Moor, local rivers and
streams. You can see water from the river Swincombe
pouring in from a pipe near the dam.

  

There are tree roots in the path in a few places.  

 

A notice for dog owners about protecting the water supply.

 

A  beautifully balanced logan stone at the top of the hill .......... or a partly submerged rock at the lakeside .....

 

Female Mallard duck.

 

The head of the lake is around to the left in this view.

 

Reflections and stones ..... a little distance below the Workman's Bridge - this is possibly the site of the "Venford Tin Mill" or part of its leat. This is deduced from a possible leat that is drawn from Venford Brook and then leads back into the brook, as depicted on the 1885/1886 25-inch OS map ..... the mill would have been at approximately SX 68366 70714, halfway along the presumed leat ..... there is no sign of this feature on the subsequent 1904/1905 map ..... the mill is listed on the Legendary Dartmoor web site as "Venford Brook Mill".....

R Hansford Worth (1967), Worth's Dartmoor, David & Charles, Newton Abbot, page 293, mentions this site as being at lat. 50°-31'-20", lon. 3°-51'-26". This converts to SX 68442 70808, further into the lake. 

 

Another view of the stones.

 

Possibly what is left of the Workman's Ford, at  SX 68410 70702. This was probably used by miners in the area and probably pre-dates the nearby Workman's Bridge.

 

This is the site of the original Workman's Bridge, SX 68351 70679 which was swept away in a violent spate many years ago, now replaced with a modern wooden footbridge over Venford Brook, just where it runs into the reservoir ..... beyond the bridge is a tree (sunlit in this photograph) behind which is a side path up to a Medieval longhouse that has been cleared of excess vegetation by the volunteers of Dartmoor Preservation Association .....

 

The longhouse ruins at SX 68223 70645. Photograph from August 2011. The site is indicated on the map below, labelled "LH" west of Workmans Ford .....
Devon & Dartmoor HER - MDV115702 - Longhouse south-west of Venford Reservoir, Holne,

 


Image © J Butler 1993. Reproduced by kind permission (ref. 29 Sept. 2012)

Map reproduced from Jeremy Butler (1994), Dartmoor Atlas of Antiquities, Vol. 4 - The South-East, Map 60, page 128. The yellow-coloured areas indicate tinners' activities. The longhouse is not mentioned in the text.

 

The spot where Venford Brook runs into the reservoir, probably the site of the Workman's Ford.

  

"Venford Fall", just above the Workman's Ford, the wooden footbridge - this is not the dramatic fall below the dam.

 

A parting view of the bridge.

 

An easy scenic path back to the dam.

 

A view with Rhododendrons.

 

The inlet of water from the River Swincombe, SX 68415 70991. The water level at the Swincombe dam is 318 m (1041 ft), here at Venford it is 285 m (935 ft), a drop of 33 m (106 ft). Out in the middle of the lake is an aeration upwelling. I started off being smart, thinking there was only one of these, so I was going to be clever and geolocate it on a map by taking compass bearings from two GPS'd locations, one each side of the lake. There were two upwellings! One is out in the middle of the lake and a second one is seen over the far side, at top left.

  

A triple mortar stone from a nearby tinners' mill ("blowing house") that is under the reservoir, SX 68568 71180 .....

  

Another view ..... 

  

Wooden plaque above the mortar stone, somewhat defaced .....  

THIS MORTARSTONE DATES TO ABOUT AD
1600 AND WAS USED AS A BASE ON WHICH
TIN ORE WAS CRUSHED CUP SHAPED
HOLLOWS WERE FORMED BY THE
MECHANICAL ACTION OF STAMPS POWERED
BY A WATERWHEEL EARLY THIS CENTURY
THE STONE WAS REMOVED FROM A SITE
ABOUT TO BE FLOODED BY THE RESERVOIR
IT WAS PLACED HERE IN 1984

From the Waymarking.com web site .....

The Plaque says: This Mortar stone dates to about AD1600 and was used as a base on which tin ore was crushed; the cup shaped hollows were formed by the mechanical action of stamps powered by a waterwheel early this century. The stone was removed from a site to be flooded by the reservoir and placed here in 1984 (not word-for-word).

  1. OS 25-inch 1886 Single Sheet map - there is possibly a tin mill leat, above the junction of streams to form the double-line drawn Venford Brook. It would take water from the brook, to the mill waterwheel, and then return it to the brook.

  2.  OS 25-inch 1905 Single Sheet map - shows "Water Works in course of construction" - completed 1907

  3. OS 25-inch 1892-1914 zoomable map - there is possibly a tin mill leat at SX 68361 70726 on the first map, above the junction of streams to form the double-lined Venford Brook.

  4. No sign of a tin mill on the 1839 Holne Tithe Map - see just above centre of the map - by the patchwork of fields - and slightly left, on the map, along Wenford Brook. Note - North Benchator and South Benchator. Tithe maps rarely showed tinning features because they were meant for " tithing" i.e. taxing one tenth of farming produce originally to support the landlords and clergy. Later, used for recording cash rents.

  5. A tin mill is described by Worth (p.293) at lat. 50°-31'-20", lon. 3°-51'-26", now flooded. This is in the region mentioned in the first map above. The lat/long location equates to SX 68442 70808 - which is by the flooded Venford Brook.
    Devon & Dartmoor HER - MDV12982 - TIN MILL in the Parish of Holne

 

Scene with the dam at the left and three upwelling sites in the reservoir and a fourth behind the bush at the right .....

  

One of the upwelling sites .....  

  


Image from Google Earth (c) 2020 

Then I looked at Google Earth - and there are ten aeration sites. 

  

 

View of the dam from the car park .....

 

Photograph taken outside the walk area, across the road from the car park, showing four features on the water-side face of the dam, presumably the original overflow outlets going under the road to cascade down the back of the dam. There is a photograph showing this in the paper mentioned above about dam design etc. describing the labyrinth weir (also linked HERE).

 

Before reaching the west car park (with toilets) at Venford Reservoir, there are two PUDC marker stones, one each side of the road, about 90 yards up Waterworks Hill - more detail below .....

 

On the rear face of the left-hand one, away from the road - is a benchmark. This is an Ordnance Surveyors mark that consists of a short horizontal line, just below the "UD" in PUDC with a government broad arrow underneath it, pointing upwards. This stone is Number 4 in the Dartefacts web site sequence of the reseroir catchment area boundary stones: across the road is Number 3.

 

Walk details

MAP: Red = GPS satellite track of the walk.


© Crown copyright 2016 Ordnance Survey Licence number 100047373
Also, Copyright © 2005, Memory-Map Europe, with permission.

 

This walk was reached by driving east from Two Bridges on the Ashburton road, turning right just before Dartmeet to Hexworthy and driving past Combestone Tor to the reservoir car park, marked on the map by the  P  symbol and the yellow cross.

 

Statistics
Distance - 3.22 km / 2.0 miles

 

All photographs on this web site are copyright © Keith Ryan.
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