The Loe
Encyclopedia
Cornwall
Cornwall is a unitary authority and ceremonial county of England, within the United Kingdom. It is bordered to the north and west by the Celtic Sea, to the south by the English Channel, and to the east by the county of Devon, over the River Tamar. Cornwall has a population of , and covers an area of...
, United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
. Situated between Porthleven
Porthleven
Porthleven is a town, civil parish and fishing port in Cornwall, United Kingdom, near Helston. It is the most southerly port on the island of Great Britain and was originally developed as a harbour of refuge, when this part of the Cornish coastline was recognised as a black spot for wrecks in days...
and Gunwalloe
Gunwalloe
Gunwalloe is a coastal civil parish and a village in Cornwall, United Kingdom. It is situated on the Lizard Peninsula three miles south of Helston and partly contains The Loe, the largest natural freshwater lake in Cornwall.-History:...
and downstream of Helston
Helston
Helston is a town and civil parish in Cornwall, England, United Kingdom. It is situated at the northern end of the Lizard Peninsula approximately 12 miles east of Penzance and nine miles southwest of Falmouth. Helston is the most southerly town in the UK and is around further south than...
it is separated from the sea by the shingle bank of Loe Bar. Both the Loe (including the southern arm known as Carminowe Creek) and Loe Bar are situated within the Penrose Estate, administered by the National Trust
National Trust for Places of Historic Interest or Natural Beauty
The National Trust for Places of Historic Interest or Natural Beauty, usually known as the National Trust, is a conservation organisation in England, Wales and Northern Ireland...
, and are designated as a SSSI by Natural England
Natural England
Natural England is the non-departmental public body of the UK government responsible for ensuring that England's natural environment, including its land, flora and fauna, freshwater and marine environments, geology and soils, are protected and improved...
. It is also designated as an Area of Outstanding Beauty AONB and is considered a classic Geological Conservation Review
Geological Conservation Review
The Geological Conservation Review is produced by the UK's Joint Nature Conservation Committee and is designed to identify those sites of national and international importance needed to show all the key scientific elements of the geological and geomorphological features of Britain...
Site.
The Loe was originally the estuary of the River Cober
River Cober
The River Cober is a short river in west Cornwall, United Kingdom. It rises near Porkellis Moor in the former Kerrier District and runs to the west of the town of Helston before entering the largest natural lake in Cornwall – Loe Pool. The water is impounded by the natural barrier, Loe Bar, and...
, a ria
Ria
A ria is a coastal inlet formed by the partial submergence of an unglaciated river valley. It is a drowned river valley that remains open to the sea. Typically, rias have a dendritic, treelike outline although they can be straight and without significant branches. This pattern is inherited from the...
or drowned river valley now blocked by a sand and shingle bar with a fresh water lake behind. The valley can be traced several kilometres out to sea. The age of the bar is disputed, with estimates ranging from several thousand years to c. 700 years. The most likely origin is a barrier beach, that gradually moved onshore, as the sea level rose during the Holocene
Holocene
The Holocene is a geological epoch which began at the end of the Pleistocene and continues to the present. The Holocene is part of the Quaternary period. Its name comes from the Greek words and , meaning "entirely recent"...
. The shingle coming from drowned terraces of the former river that flowed down the English channel
English Channel
The English Channel , often referred to simply as the Channel, is an arm of the Atlantic Ocean that separates southern England from northern France, and joins the North Sea to the Atlantic. It is about long and varies in width from at its widest to in the Strait of Dover...
. It is thought that Longshore Drift
Longshore drift
Longshore drift consists of the transportation of sediments along a coast at an angle to the shoreline, which is dependent on prevailing wind direction, swash and backwash. This process occurs in the littoral zone, and in or within close proximity to the surf zone...
plays an important part in the maintenance of the Bar, with a strong current flowing to the south-east from Porthleven to Gunwalloe, depositing shingle along the Bar. The ebb flow is not a simple reverse flow and is not strong enough to remove all the deposits. The bar itself is a sediment sink as far as the overall beach budget is concerned. The deposits have been tentatively dated as Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...
, and compared with Gunwalloe beach material very little of the Loe Bar shingle is locally derived. The composition of the Bar deposits are: Chalk
Chalk
Chalk is a soft, white, porous sedimentary rock, a form of limestone composed of the mineral calcite. Calcite is calcium carbonate or CaCO3. It forms under reasonably deep marine conditions from the gradual accumulation of minute calcite plates shed from micro-organisms called coccolithophores....
flint
Flint
Flint is a hard, sedimentary cryptocrystalline form of the mineral quartz, categorized as a variety of chert. It occurs chiefly as nodules and masses in sedimentary rocks, such as chalks and limestones. Inside the nodule, flint is usually dark grey, black, green, white, or brown in colour, and...
86%, Quartz
Quartz
Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...
9%, Grit
Gritstone
Gritstone or Grit is a hard, coarse-grained, siliceous sandstone. This term is especially applied to such sandstones that are quarried for building material. British gritstone was used for millstones to mill flour, to grind wood into pulp for paper and for grindstones to sharpen blades. "Grit" is...
2.6%, Greensand
Greensand
Greensand or Green sand is either a sand or sandstone, which has a greenish color. This term is specifically applied to shallow marine sediment, that contains noticeable quantities of rounded greenish grains. These grains are called glauconies and consist of a mixture of mixed-layer clay...
chert
Chert
Chert is a fine-grained silica-rich microcrystalline, cryptocrystalline or microfibrous sedimentary rock that may contain small fossils. It varies greatly in color , but most often manifests as gray, brown, grayish brown and light green to rusty red; its color is an expression of trace elements...
2% and Serpentine 0.5%. The nearest onshore source is 120 miles away in East Devon.
To prevent flooding in parts of Helston
Helston
Helston is a town and civil parish in Cornwall, England, United Kingdom. It is situated at the northern end of the Lizard Peninsula approximately 12 miles east of Penzance and nine miles southwest of Falmouth. Helston is the most southerly town in the UK and is around further south than...
, the Bar has occasionally been breached, a practice known locally as "cutting". However, it has always naturally resealed itself.
Historical Records
- C13th. The townspeople of Helston buy the rights to the port of GweekGweekGweek is a civil parish and village in Cornwall, United Kingdom. It is situated approximately three miles east of Helston. The civil parish was created from part of the parish of Constantine by boundary revision in 1986...
at the head of the Helford RiverHelford RiverThe Helford River is a ria located in Cornwall, England, UK, and not a true river. It is fed by a number of small streams into its numerous creeks...
as Helston did not have access to the sea.
- 1272 King Edward I granted certain lands in or near Helston to William de Treville on condition that he should, at his own expense, bring a boat and fishing-hook and net for the King's use on the Loe, as often as he should visit the Borough.
- 1281 The first documentation of the name Penrose; John de Penrose.
- 1534-43 Visits by John Leland. First to mention the "casting up of sands that made a bar stopping the River Cober from flowing out to Sea."
- 1602 Richard Carew. "The shingle was relatively porous and fresh water could leave and seawater enter depending, on the relative heights of the pool and sea".
- 1771 Penrose bought by the Rogers family for £11 000.
- 1780 AditAditAn adit is an entrance to an underground mine which is horizontal or nearly horizontal, by which the mine can be entered, drained of water, and ventilated.-Construction:...
constructed to prevent back-flooding of the silverSilverSilver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...
and leadLeadLead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...
mine Castle Wary, also known as Wheal Pool.
- 1807 Over one hundred people were drowned when the Captain of HMS AnsonHMS Anson (1781)HMS Anson was a 64-gun third rate ship of the line of the Royal Navy, launched at Plymouth on 4 September 1781 by Georgina, Duchess of Devonshire.-History:...
, beached the 44-gun frigateFrigateA frigate is any of several types of warship, the term having been used for ships of various sizes and roles over the last few centuries.In the 17th century, the term was used for any warship built for speed and maneuverability, the description often used being "frigate-built"...
on the Bar when caught in storm on her way to the BrestBrest, FranceBrest is a city in the Finistère department in Brittany in northwestern France. Located in a sheltered position not far from the western tip of the Breton peninsula, and the western extremity of metropolitan France, Brest is an important harbour and the second French military port after Toulon...
blockade. A memorial cross to the dead can be seen on the coastal slope near Carminowe Creek. A consequence of this disaster was the development of the rocket life-saving apparatus by Henry TrengrouseHenry TrengrouseHenry Trengrouse inventor of the ‘Rocket’ life-saving apparatus, was born at Helston, Cornwall, England, United Kingdom, on 18 March 1772....
who witnessed the wreck, and an Act of ParliamentBurial of Drowned Persons Acts 1808 and 1886The Burial of Drowned Persons Act 1808, also known as Grylls' Act, is an Act of the Parliament of the United Kingdom . The act provides that unclaimed bodies of dead persons cast ashore from the sea should be removed by the churchwardens and overseers of the parish, and decently interred in...
for the Christian burial for those lost at sea.
- 1837 Report on the possibility of creating a harbour by the civil-engineer James Rendle. The estimated cost of £118 523 was considered too expensive to take the project further.
- c. 1850 Tin waste from the mines at PorkellisPorkellisPorkellis is a village in Cornwall, United Kingdom. It is situated approximately three and a half miles north east of Helston, and is located in the heart of the old Wendron mining district....
Moor begin to block the inner face of the Bar reducing the porosity.
- 1865 Breach of the Bar.
- 1874 The last known occurrence of manual cutting.
- 1889 Enlargement of the 1780 adit which regulated outflow.
- 1924 Freak wave caused flooding in Helston.
- 1938 Mining activity ceased up river.
- c. 1940 Loe Bar mined and timber baulks or booms moored on the surface of the Loe to prevent seaplanes landing. A pillboxBritish hardened field defences of World War IIBritish hardened field defences of World War II were small fortified structures constructed as a part of British anti-invasion preparations. They were popularly known as pillboxes by reference to their shape.-Design and development:...
was built near Bar Lodge. By 2010 erosion had caused the pillbox to fall onto the beach.
- 1974 Ownership of the Penrose Estate (apart from the house) is transferred to the National TrustNational Trust for Places of Historic Interest or Natural BeautyThe National Trust for Places of Historic Interest or Natural Beauty, usually known as the National Trust, is a conservation organisation in England, Wales and Northern Ireland...
.
- 1979 First time a channel is cut by JCBBackhoeA backhoe, also called a rear actor or back actor, is a piece of excavating equipment or digger consisting of a digging bucket on the end of a two-part articulated arm. They are typically mounted on the back of a tractor or front loader...
.
- 1984 Heavy rains in October and November lead to the last cutting of the 20th century.
Site of Special Scientific Interest
Geomorphology
Geomorphology is the scientific study of landforms and the processes that shape them...
as it is formed by a barrier beach moving onshore since the Holecene and maintained by a predominantly south-west wave regime. During storms the Bar can be overrun by the sea forming a series of washover fans resulting in, annual laminated sediments, which are unique in Great Britain.
The habitat is unique in Cornwall with rare species of plants, bryophytes, algae
Algae
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...
and insects. It is also an important overwintering site for nearly 80 species of birds and up to 1200 wildfowl. At the last assessment on 8th September, 2010 the lake was found to be unfavourable condition, with no change from the previous assessment. The reasons being inappropriate water levels, and water pollution due to agriculture run off and discharge.
Loe Bar is the only site in Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...
where the subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
leechi of the Sandhill Rustic
Sandhill Rustic
The Sandhill Rustic Luperina nickerlii is a noctuid moth found in various parts of western and central Europe with several subspecies.-The Sandhill Rustic in Britain:...
moth
Moth
A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth , with thousands of species yet to be described...
is found.
Porcellio dilatatus is an uncommon species of woodlouse
Woodlouse
A woodlouse is a crustacean with a rigid, segmented, long exoskeleton and fourteen jointed limbs...
with scattered records from most of the British Isles. Loe Pool is the only Cornish site. Also found on each of the inhabited islands of the Isles of Scilly
Isles of Scilly
The Isles of Scilly form an archipelago off the southwestern tip of the Cornish peninsula of Great Britain. The islands have had a unitary authority council since 1890, and are separate from the Cornwall unitary authority, but some services are combined with Cornwall and the islands are still part...
.
Folklore
The Loe is reputed to be the lake in which Sir BedivereBedivere
In Arthurian legend, Sir Bedivere is the Knight of the Round Table who returns Excalibur to the Lady of the Lake. He serves as King Arthur's marshal and is frequently associated with Sir Kay...
cast King Arthur
King Arthur
King Arthur is a legendary British leader of the late 5th and early 6th centuries, who, according to Medieval histories and romances, led the defence of Britain against Saxon invaders in the early 6th century. The details of Arthur's story are mainly composed of folklore and literary invention, and...
's sword, Excalibur
Excalibur
Excalibur is the legendary sword of King Arthur, sometimes attributed with magical powers or associated with the rightful sovereignty of Great Britain. Sometimes Excalibur and the Sword in the Stone are said to be the same weapon, but in most versions they are considered separate. The sword was...
.
A local legend states that the giant Tregeagle was doomed to remove the sand from Gunwalloe to Porthleven, from which the sea would return it. In the course of one of his journeys he is said to have dropped a bag of sand at the entrance of Helston harbour and so to have formed the Bar. Local superstition also warns that the Loe claims a victim every seven years.