Areas of Expertise
Pehur High Level Canal
The Pehur High Level Canal, North-West Frontier Province, Pakistan. This is thought to be the world’s largest true parabolic canal, designed by Adrian Laycock.
The parabolic profile of concrete lining is superior to the normally-used trapezoidal
section and imparts great strength and resistance to cracking from slumping, settlement or
soil movement. It is also easy to construct using a rotating striker tube.
Most canals are built to a trapezoidal profile. Parabolics offer several advantages:
Strength. The shell shape offers great structural strength with no points of weakness such as occur in a trapezoidal profile.
Ease of construction. No problems of slumping or tension cracking during concrete placement that occur near the base of a trapezoidal slope. The actual gradient of the lower profile is much flatter than for a trapezoidal.
Cost. Volume of concrete and excavation can be reduced over an equivalent trapezoidal profile.
Speed. This method of construction is fast. Slipforming can also be used, although the machinery is expensive.
Beauty. It is a rare thing for engineers to combine functionality with beauty, but here it is.
The self-regulating float-controlled gates are designed to automatically regulate the downstream water level to a predetermined level. With downstream control, flexibility of supply on the main canal system is guaranteed. Response time of the 100 mile-long canal system is cut from days to hours, and wastage of water and power generation at Tarbela Dam can be reduced.
Merowe Irrigation Project, Sudan
This massive project is now undergoing detailed design. A dam on the Nile is already under construction at the 4th
cataract. The irrigable area will extend for 400 kilometres downstream. Adrian Laycock is irrigation design consultant
to Lahmeyer International. The irrigation system will include pumping and parabolic gravity canals, and automatic
pipeline distribution systems. The terrain is extremely hostile and requires some careful engineering. Existing
projects in the area have been affected by salinity, moving sand dunes, waterlogging and dispersive silts which
have severe constraints on canal design and operation.
Irrigation Rehabilitation (Pakistan)
A proportional division structure on the Swabi SCARP irrigation rehabilitation project, Pakistan.
A design introduced by Adrian Laycock as a means of passive automation for this century-old project
of 100,000 hectares.
Precast Parabolic Canal
Small precast parabolic canal. Adrian Laycock has introduced these in Indonesia, India and Pakistan, where
they have proved a runaway success in rehabilitation of watercourses. They are made of high strength
unreinforced concrete and can be fabricated under controlled conditions in small casting yards,
providing basic principles of quality control are followed. They have the triple advantages of
being cheap, long-lasting and hydraulically efficient.
The Yeleru Left Bank Canal
The Yeleru Left Bank Canal carries water 150 km to the new industrial
town of Vishakapatnam in Andra Pradesh, India. The canal leaks badly and
is severely affected by instability of its side slopes which are in deep
cut for much of its length. Adrian Laycock is consultant to Lahmeyer
International in formulating engineering rehabilitation works, including
bentonite grouting of canal banks, slope stabilisation, canal lining and
Irrigation Rehabilitation (Albania)
Albania - rehabilitation of irrigation schemes.
Top right - A pump station near Vlore.
Below left - Saline land near Vlore.
Below right - Rehabilitation of irrigation schemes amidst the Fier oilfield.
Radial-Gated Cross Regulator
Semi-closed Pipeline Network
Installing a low-pressure semi-closed pipeline network, Pakistan. The design principles of this demand-scheduled irrigation system are quite different from those normally used. The tail-end problem is eliminated, and farmers are able to take water at any time to suit themselves or their crop, without being restricted to a tightly-regimented supply schedule.
This is a new concept for Pakistan and represents a major shift from traditional irrigation principles.
The design procedures were developed by Adrian Laycock, based on the philosophies of Professor John L
Merriam. Pressure control is achieved through float-operated Harris Valves.
Land Drainage in Argyll
This work became necessary after the installation of a sewer pipeline caused
damage to an existing underground field drainage system. A field is being
re-drained using gravel and geotextile filters.
Irrigation Rehabilitation (Armenia)
Adrian Laycock was technical auditor for a USA-financed rehabilitation project.
Irrigation Engineering Portfolio
Adrian Laycock Ltd was established in 1982 and has been active in irrigation development in the following countries :
The company was set up to work on the interface between civil engineering and other disciplines such as agriculture, ecology, the environment, sociology, management, economics, soil conservation, which come together in most irrigation projects and often give rise to conflicting solutions for development.
Operating from its base in Scotland, Adrian Laycock Ltd is a small scale organisation which maintains close working links with independent specialist consultants in related fields. Much of its work is in providing specialist expertise to larger international consultants.
© Adrian Laycock Ltd 2000. Fair use and distribution of this material is encouraged provided proper citation is given.