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Blue Lake in Earlier Times
Blue Lake in May 2004
Blue Lake - A Vision
Blue Lake Restoration in Progress
Images from this project
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Blue Lake Restoration in Progress
Location: Redcar and Cleveland
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.jpg "Digger making access at the south end of the lake.") Following a period of extensive planning by the management group the dredging contractors, Land and Water, moved in to start work on clearing the lake towards the end of September 2004.
 One very important feature of Blue Lake is it’s by pass channel. This channel transfers the water from the stream above the lake directly to the stream below the lake and first thoughts would suggest that this channel would have been brought into use only occasionally to allow the lake to be emptied for maintenance purposes. Documents from the sale of the property in 1903 have recently been found, suggesting that the usual state of flow was along the bypass channel and that water would be diverted into the lake only when there was a need to replenish it. In this way the lake would have been maintained as silt free as possible. Of course when the lake was in need of cleaning out the by pass channel would be kept running and the water drained from the lake. So in September 2004 after many years of inactivity the by pass channel was brought into use once more. A channel was excavated from the stream above the lake along the bank at the side furthest from the track.
 The channel which is about 800 mm wide was continued for about one hundred metres to join the original concrete and brick construction which can be seen emerging from the woods close to the weir and spilling into the stilling pond below the dam. When the by pass channel was dredged the fall of its bed was decided by the flow of water which occurred as the digging took place.
 At one stage the channel seemed to go up hill and the optical illusion was made further convincing by the fact that the water did not flow. In fact it turned out that the bed of the channel was leaking into the lake, possibly along old tree roots and the installation of a plastic liner for a few yards solved the flow problem and proved that the fall of the channel was indeed downstream as intended. (Images October 2004)
 With the feed to the lake safely diverted it was now time to dig out the lake itself. It was important to make sure that the excavation was deep enough to remove the majority of the silt which had accumulated over the years but not so deep as to damage the clay lining in the bed of lake. The depth of excavation had been estimated some months earlier when the lake was surveyed using scaffold poles driven into the silt. This depth was estimated to be about three metres below the overflow level of the weir. (Image October 2004)
 Over one thousand cubic metres of material was moved from the lake across the track and deposited on the cleared forestry. (Image 4th October 2004)
 The sides of the lake were thought to be cobbled but turned out not to be so clearly defined as first thought. This led to some nervous moments when the silt around the valves had to be excavated, but the contractors took care to avoid any damage. Parts of the lake turned out to be brick lined and volunteers were able to locate the main sluice valve so that it could be dismantled. (Image 4th October 2004)
 This allowed the lake bed to be kept clear of water, which is now flowing through the dam and back into the stream via the dam have been rebuilt. The stones have been bonded with mortar to prevent wave damage on the front face. In due course the sides of the weir will be restored and the gaps between the walls filled.
 It was now the turn of local volunteers to take full control over the site. The remainder of the silt covering the main valve and drain valve was dug out, bucketed to the top of the dam and burrowed away.
 The two outlets were cleared. It was discovered that the operating spindle for the main valve was missing. This main valve is a sluice valve feeding the pipe which once provided water to power machinery at Home Farm. The drain valve, a gate valve, was found to be in very good condition.
 The drain outlet was located downstream of the dam and a start made on rebuilding the stilling pond which was designed to take the energy from the flow of water and so preserve the sides of the stream below the dam. The walls of the stilling pond are being built from mortared stonework and suitable stones are being obtained from around the site to form the bed of the pool. The drain outlet is now running and the gate valve has been removed for repair. (Image 22nd March 2005)
 A start has been made to repair the eroded parts of the dam. This was built with a puddled clay core retained with dry stone walls at each side. The weir end of the dam is being renovated and the image shows the clay core beneath the weir in place. It is intended that the weir will be widened by some nine inches. Part of the front wall is to be rebuilt with the stones bonded with mortar to prevent wave damage.
 The weir at the end of the dam is being widened by some nine inches and the extension floor slab has been cast. Part of the walls of the dam have been rebuilt. The stones have been bonded with mortar to prevent wave damage on the front face. In due course the sides of the weir will be restored and the gaps between the walls filled. (Image 22nd March 2005)
 Some work is being done to repair a drain under the track leading to the lake. Two cast iron pipes in good condition have been discovered nearby and these are to be used to replace a damaged plastic pipe. (Image 22nd March 2005)
 A flight of steps have been formed at the upstream end of the lake. These will give access to a dipping platform which is to be built shortly. (Image 20th May 2005)
 The dipping platform is on two levels the higher level intended as a picnic area. (Image 2nd March 2006)
 Severe weather caused flooding in several locations around Guisborough on Friday 15th April 2005. Blue Lake briefly filled up as the storm flows ran through the catchments. However, this didn't cause us any significant problems apart from some loss of building materials washed away by the flood waters. Build-up of gravel in the drain pit is a continuing irritation that we are having to deal with on a weekly basis.
 The walls of the weir have been rebuilt on the extended concrete base and the tops have been capped with stone. (Image 20th May 2005)
 During the last few years the original spillway became severely eroded and much of the masonry disappeared downstream. A deep chasm formed below the weir and this had to be filled with clay and compacted. Difficulty of access due to severely wet conditions in April made the task very difficult and it was completed in May. (Image 20th May 2005)
 The foundations of the new spillway have been formed. The image shows the boards and pegs in place. The boards were bent so as to form a smooth curve and shaped to provide a suitable camber. Bending of the boards was achieved by standing them flat in water, supporting them at each end and placing a heavy sack between the supports. The image shows the foundation profile being checked with a suitably shaped board. (Image 26th June 2005)
 The brickwork sides of the spillway from the bypass channel are being refurbished. The concrete base was found to be in remarkably good condition. Bricks donated by Forest Enterprise were recovered from the old kennels ruin below Bousdale House and were used for this purpose. (Image 26th June 2005)
 The refurbishment of the spillway is complete. This image shows the spillway looking down towards the stilling pool. (Image 2nd March 2006)
 This is the spillway looking upwards towards the weir at the top of the left hand branch and the bypass entering on the right. (Image 2nd March 2006)
 The bypass channel has been widened further in recent months and is now complete. This has necessitated manual digging of the material along the full length of the lake and further. The image shows the finished channel as it joins the top of the spillway. (Image 2nd March 2006)
 The Flow Diversion stoplogs have been built at the upstream end of the lake. These will ensure that there is always a small flow going into the lake through the channel (bottom of the image), with storm flows going round the bypass channel (top of the image), taking any debris with them. However, at the very highest flows in order to ensure that the bypass doesn't overflow, some of the storm flow will go through the lake. (Image 2nd March 2006)
 The dam is almost complete and awaits reinstallation of the valves before the lake can be filled. The image shows the dam viewed from the bed of the lake with the weir at the top left and the stonework complete. The wooden pallet covers the valve housings. (Image 2nd March 2006)
 The new timber frame which will carry the operating rods for the refurbished drain and outlet valves is prepared on site. (Image 10th June 2006)
 The partly assembled timber frame is ready to be hauled upright and bolted to the original (1880) posts. (Image 10th June 2006)
 The refurbished outlet valve is ready for connection to the operating rod. (Image 10th June 2006)
 The refurbished drain valve is connected to it’s operating spindle. (Image 10th June 2006)
 The posts are in place and the metal beam securing the structure to the dam wall is attached. The operating spindle to the drain valve is complete and the spindle to the outlet valve awaits connection. Checks are being made from the temporary staging. (Image 10th June 2006)
 All connections have been made and the grids covering the two valves are in place. (Image 10th June 2006)
 The valves were closed during the weekend of 24th/25th June. This was the scene four weeks later following a period of drought in the area. The lake is almost full. (Image taken 19th July 2006)
 To complete the work a new interpretation board has been installed above the dam. (Image taken 19th July 2006)
During the work local wildlife has been keeping an eye on proceedings – amongst the sightings have been deer and a kingfisher. We hope they will become regular visitors.
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