Linking cities, towns and villages,Britain’s 200-year old inlandwaterways were once the

primary method of transporting goodsand were the catalyst for the world’sfirst industrial revolution. The canalsbuilt were cutting-edge engineeringsolutions of their time, enabling inlandwaterways to flourish until theemergence of the railways in the 19thcentury.

Following post-world war declineand disuse, inland waterways are todayenjoying a new role in twenty-first-century society. An important part ofour heritage, canals and rivers arehome to varied wild life habitats and area leisure resource enjoyed by all.

British Waterways is the publiccorporation which cares for 2000 milesof canals and rivers across England,Scotland and Wales. Attracting 10million visitors each year, BritishWaterways’ canals and rivers havebecome catalysts for both urban andrural regeneration. Their modern-daymaintenance and restoration demandsengineering solutions that continue tobe both innovative and considerate tothe wildlife and visitors who enjoy them.

A brief historyWater has been used for transportsince primitive times – for carryinggoods and ferrying people. At firstrivers were used, but rivers canmeander and be unpredictable. TheRomans created the first man-madeBritish navigations such as theFossdyke, while the short Exeter Canalwas first cut in 1566. However, itwasn’t until the late 18th century thatBritain acquired the unique network ofcanals and river navigations that weknow today and, by 1793, the countrywas in the grip of ‘Canal Mania’.

Pioneering engineers built structuresnever attempted before and today’sexistence of our waterway network istestament to their dedicated work.Waterways climbed slopes by means offlights of locks or around individualplanes, were conveyed through hills intunnels and were carried across valleyson high aqueducts. Many are still asgood as new today, like Telford’s 300 mPontcysyllte Aqueduct in Wales orBingley Five Rise Locks near Leeds.

The arrival of railways broughtcompetition that began the decline ofcargo carrying on canals but it was in

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STEWART SIM OBEOPERATIONS DIRECTORBRITISH WATERWAYS

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Regeneratingthe waterways

£2 billion has been spent onregenerating the BritishWaterways network over thepast ten years. From the re-lining of large stretches ofcanal, to the restoration of thecollapsed Standedge Tunnelthat was originally deemedimpossible, the engineers havebeen challenged every step ofthe way. Here, Stewart Simgives an overview of thevarious projects that have beenundertaken, detailing work onthe rejuvenated Anderton BoatLift and the state-of-the-artFalkirk Wheel

motorways that effectively killed offwidespread waterway freight.

The waterways entered publicownership in 1948 and in 1962 TheTransport Act created the BritishWaterways Board to operate the2000 mile inland waterway network.Later, the 1968 Transport Act gave firstofficial recognition to the value of theinland waterways for recreation.

By the mid-1990s, after manydecades of under-funding for thewaterways, British Waterwayssuccessfully made the case forincreased investment in the network, aspioneering regeneration schemes beganto demonstrate the economic, socialand environmental potential ofrevitalised waterways. New funds fromthe European Union, RegionalDevelopment Agencies and the NationalLottery – particularly the MillenniumCommission and Heritage Lottery Fund– unlocked stalled restoration projects,which dated back decades.

A resource for allThe waterways are a leisure resourcefor all: half the UK population liveswithin five miles of a British Waterwayscanal or river. Well kept canals andrivers improve the environment we livein, ensuring visitors are able to enjoy abroad range of leisure facilities includingwalking, running, angling, cycling andcanoeing or simply visiting a canal-sidepub, restaurant or museum.

The boats on canals and riversremain a common and attractive sightand are central to waterway life. Today’scraft are predominantly leisure boatsthat bring colour and life to waterways,making them fun and vibrant placesand attracting people to the canaltowpaths and lock sides.

A 200-year history ensures thewaterway network is an integral part ofthe nation’s heritage. Visitors enjoy over2800 listed structures and more than130 Scheduled Ancient Monuments,over 800 designated conservation sitesand 100 Sites of Special ScientificInterest (SSSI). Magnificently engineeredstructures, landscapes and traditionsare becoming increasingly valued.

Whilst leisure and tourism on canalsand rivers continue to thrive, somecommercial vessels still use the networkas an efficient method of transportingappropriate goods. The movement offreight on inland waterways has a smallalthough growing part to play in thegovernment’s plans to managetransport more effectively. Total freightcarried each year is 3.5 million tonnesand British Waterways has plans todouble this figure by 2013.

Regeneration andrestorationThe same towns and cities that turnedtheir backs on the waterways in theyears of decline and dereliction are nowrediscovering historic canals, basins,locks, warehouses and wharves as thefocal points of vibrant renaissance. Insimple terms, people want to live, work,socialise and relax by water. Todaywaterways are an acknowledgedregenerative catalyst, delivering tangibleeconomic, social and environmentalbenefits to the lives of millions acrossthe nation.

Over the last decade, BritishWaterways has been involved in£2 billion worth of regeneration that hasbought widespread social andeconomic benefits to both urban andrural communities, creating thousandsof jobs. The recent renovation of the

mainly rural Huddersfield Narrow Canal,for example, is helping to create some3000 jobs and an annual visitor spendof £3.6m.

The decline of canals led to manymiles of waterways being abandoned orcut off. After half a century of uncertaintyand underfunding, canal restoration hasgained momentum with the completionof many key projects. In the last twoyears alone, 220 miles of waterway havebeen restored or opened – and even anew navigation constructed – in eightmajor restoration projects.

In each major restoration BritishWaterways engineers tackle majorobstructions, restore unique historicstructures and buildings that requireinnovative and state-of-the-artengineering solutions. Recent projectsinclude the following:

The Anderton Lift at Northwich inCheshire is one of the best examples ofhow to make improvements – in closeconsultation with conservation bodieslike English Heritage – whilst stillpreserving a unique structure.

The lift was built in 1875 to transportcargo-carrying boats between the RiverWeaver and the Trent & Mersey Canal15 m above. It is the world’s oldestboat lift and known with some affection

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In the last two years alone, 220 miles ofwaterway have been restored or opened in

eight major restoration projects

Figure 1 Refurbishment work on theManchester Rochdale lock

as the ‘Cathedral of the Canals’. Builtusing a revolutionary system ofhydraulics, Anderton led to a number ofsimilar lifts being built in Europe andNorth America.

In 1875, the Anderton Boat Liftused two water-filled tanks (caissons)counterbalancing each other andsupported on massive hydraulic rams.The lift worked on the deceptivelysimple principle that drawing a smallquantity of water from the ascendingtank created a difference in weight.This, with the aid of a small hydraulicaccumulator, was all that was neededto cause the heavier tank to descendand the other to rise. The hydraulicrams were operated by a steam engineand pump which was converted toelectricity in 1908 when engineeringwork adapted the lift, counterbalancingeach tank separately and operating thewhole system mechanically.

The restoration work completed in2002 reverted back to the 1875 modeof operation. The work includeddismantling the structure for repair andtook a team of 20 welders and erectorsten weeks to loosen, drill-out or burn-out 3000 bolts. The replacementhydraulic ram shafts replicate the

originals and some 1500 m of weldingcovers more than 1000 repairs to thestructure.

Restoration of the Kennet & AvonCanal shows how restoring waterwayscan benefit the environment. The canalfeatures some of the finest waterwayarchitecture in the country and passesthrough beautiful, fertile countrysideand historic towns and cities includingBath, Bradford-on-Avon and Devizes.

In November 1997 a ‘giant bath-plug-pulling’ ceremony marked the startof a five-year £29 million restorationproject. Extensive relining andconservation work took place along thelength of the navigation, including a10 mile, £11 million stretch betweenBath and Bradford-on-Avon which hasalways leaked, wasting precious water.

The work was both technicallyinnovative and also paid specialattention to the protection of thewaterway’s important wildlife, includingwater reeds, fish and voles.

Engineers overcame differentchallenges along the canal, involvingpiling, dredging, installation of apipeline, numerous lock repairs, water-saving back pumping and constructionof water control weirs.

Hills used to be a canal builder’snightmare – until The Falkirk Wheelopened in July 2002. The wheel is theworld’s first rotating boat lift andcentrepiece of the £84.5 millionMillennium Link which has restored andreconnected Scotland’s sea-to-seaLowland canals and also Glasgow toEdinburgh, creating a corridor ofenvironmental, economic and leisureopportunities across central Scotland.

The recipient of many engineeringand design awards, the wheel usestwenty-first-century technology tocreate a twenty-first-century icon forwaterways and for Scotland.

Itself costing £17.5 million, The FalkirkWheel Interchange replaces an originalflight of 11 locks that would have used asignificant volume of water as boats‘cycled the lock’ during their transitthrough the flight.

The wheel design uses Archimedes’principle to provide very efficient rotationin terms of energy. Up to eight boatsenter each gondola and the weight isbalanced by the displacement of waterin each. In April 2002, a team from BBCTomorrow’s World conducted anexperiment on site to illustrate the lowpower levels required to keep TheFalkirk Wheel turning. Remarkably, thepower required is approximately 18 kW,which Tomorrow’s World compared tojust ten household toasters.

A comprehensive environmentalstudy was carried out prior to workcommencing at The Falkirk Wheel. Asthe wheel was situated on a formeropen cast mine, ground conditions andcontamination issues on the brownfieldsite had to be examined in detail andsolutions identified. Activity included theremoval of over 80 000 tonnes ofmercury contaminated sediment fromthe adjoining Union Canal.

The three-mile Standedge Tunnel, onthe Huddersfield Narrow Canal, is theUK’s longest, highest and deepest.Restoration was thought ‘impossible’,as the tunnel had collapsed in anumber of places with 200 m ofPennine rock bearing down on the1811 structure.

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Figure 2 Relining a stretch of the Kennet & Avon Canal near Bath

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The Anderton Boat Lift –design of the hydraulicsystemThe hydraulic rams, and associateddrive and control equipment weredesigned, constructed and installedby Bosch Rexroth in a £1.5 millioncontract. Each of the two cylindersand plungers consists of a steel tube,with the plungers protected with aspecial ceramic coating. The overalllength of the rams is over 17 m.

The basic performancespecification for the system was theability of the cylinders to work inisolation mode or as a pair inbalanced mode and to have a degreeof system redundancy. Additionalpump sets and control features wereadded to the basic principle tocomplete the design.

The original intention of the restora-tion project was to automate a systembased as far as possible on theoriginal, but using mineral oil as theoperating fluid for increased life. Thissystem relied on a difference of waterlevels between the two caissons;150 mm of water was drained fromthe lower caisson, making it lighterthan the upper caisson. However thesize of the cylinder required for

Guidegrames

Caissongates

Rivergates

River

Canal

Oil

South aqueductgates

North aqueductgates

Aqueduct

Supportlegs

Longitudinal section

mechanical strength and the differencein water level, provided a differentialpressure of only 4 bar. This would beinsufficient to overcome the friction ofthe cylinder seals and would not providegood control with a proportional flowcontrol valve.

The alternative design used a ‘fullypumped’ system, where the oil flowbetween the two cylinders was boostedthrough a variable displacement pump.The displacement of the two cylindersis effectively the same, so a closed looppump was selected and able to accept

flow in both directions as thecaissons rise and fall.

The hydraulic reservoir, pump setsand main control cabinet were housedin an extension to the existing 19thcentury brick building below theaqueduct. The mains electrical sub-station, containing two 500 kVAtransformers to power the lift as wellas rest of the site, was accommodatedin the existing building. The buildingwas sympathetically designed tomatch existing and former buildings onthe site.

Figure 3 A side profile of the lift inthe early 1990s, beforerestoration work began

Figure 4 Reconstruction ofthe boat lift,September 2001

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The Falkirk Wheel –rotating the liftThroughout the design andconstruction of The Falkirk Wheelthere were many issues andengineering solutions to consider.Challenges were varied and includedaesthetical issues such as integratingthe design of the aqueduct leading tothe wheel into the design of the boatlift, and construction issues such asboring large diameter, 25 m concretepiles down to rock because of anunderlying open cast infill.

The wheel itself does not need arim and turns by ten hydraulic motorsacting directly on to a centre axle.The axle sits on bearings at eitherend, with the outer part of onebearing fixed to the building at theback of the wheel, and the outer partof the other being fixed to thereinforced concrete ‘mouse hole’ atthe north end of the wheel structure.The inner section of the bearing isfixed to the central axle and operates

Figure 5 Construction work underway

Figure 6 Christmas lights switch-on, December 2002

like a slewing ring on a crane, exceptthat it sits vertically, not horizontally.The north end of the axle has nodrive and hence the central tubemust transmit the driving force viatorsion along its full length. Hence theoriginal desire for a glazed centraltube was impractical. The power todeliver the hydraulic pressure to themotors is provided by two electricmotors which uses about 18 kWwhen turning the 1800 t structure –1k W for every 100 t.

The gondolas are supported ontwo pairs of bogey wheels on eachside which run on a rail which is bentto a diameter of about 8 m and fixedto the wheel arms. This means that,as the axle rotates, they run along therail and stay horizontal. A large cogfixed to each gondola and one to theback of the wheel building, along withthe two smaller idler gears fixed tothe wheel arms, ensure that thegondolas do not tip as the wheelrotates.

communities who enjoythem. Many commercialpartnerships have beengenerated and, as a notfor profit organisation,British Waterwaysinvests income backinto waterwayimprovement projects.

Projects with theprivate sector includethe supply of a range ofwater and wastewaterservices and theinstallation of a 400 milefibre-optic networkunder towpaths. Inregards to property, arecently formed publicprivate partnership willdevelop and regeneratenumerous canal sidelocations in run-down inner city areas.

An important part of Britain’s heritage,canals and rivers have evolved and nowhave a valuable role in 21st centurysociety. Maintaining and restoring thecanals and historic structures requiresboth innovative and technicalengineering solutions. The investment innew and restored structures is morethan justified by the ever increasing

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numbers of visitors who enjoy the canalsand rivers, and the environmental andeconomic returns that regenerationbrings. The message from governmentis that inland waterways are to bemaintained in a sustainable way so thatthey fulfil their social, economic andenvironmental potential, and theircommitment together with BritishWaterways’ commercial approach isensuring a resource for all, both todayand for future generations. ■

Stewart Sim is aCharteredEngineer, a fellowof the Institute ofCivil Engineersand a Member ofthe CharteredInstitute ofEnvironmental Management. He hasworked for British Waterways for 29years and is responsible for theoperation, management andmaintenance of the 2000 milenetwork of canals and riversthroughout England, Scotland andWales.

Last year, against all the odds,Standedge Tunnel reopened after apainstaking rebuilding programme. Intotal, 16 000 tonnes of rock, silt anddebris were removed and the tunnelwas then secured with over 6000 rockbolts, 6000 m2 of spray concrete, andnew brick linings.

When canals fell into disuse it wascommon for roads, railways, buildingsand even whole town centres to bebuilt across their path, with no thoughtfor future restoration. The RochdaleCanal which opened in March 2003had 15 miles restored as part of theambitious project to re-open a 32 milenavigation stretching from Manchesterto Sowerby Bridge in Yorkshire. The£25 million restoration included 24 newlocks and 12 new road bridges, andthe finished waterway is now acting asa catalyst for urban regeneration alongits route.

Close to Rochdale town centre, theterminus roundabout of the A627(M)was a major engineering challenge forBritish Waterways. The bright idea toovercome this significant 250 mblockage involved putting the canal in atunnel, lifting the junction by up to twometres and converting the roundaboutinto a sophisticated crossroads andtraffic light system which could dealmore efficiently with greater volumes oftraffic. Similarly, where the M62motorway had crossed the then derelictcanal, engineers had to once againtunnel under the road.

Working in partnershipAn extraordinary turnaround in thefortunes of the waterways is largely dueto a countrywide collaboration betweena broad range of different public, privateand voluntary bodies including: localand national government; the lottery;the European Union; canal societies;development agencies; and commercialcompanies.

British Waterways is also successfullyadopting a commercial approach andblending it with public sector values forthe benefit of the waterways and the

Figure 8 Rock bolting of Standedgetunnel

Figure 7 Relining of the StandedgeTunnel