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Facts and figures

FinancingThe total cost of building Södra Länken has been estimated at SEK 7.7billion (June 2002 price level) including land acquisition costs. StockholmCity is contributing about SEK 1.3 billion of the cost. The Swedish NationalRoad Administration was commissioned by the Government to build andfinance Södra Länken. The Stockholm Region of the Swedish National RoadAdministration was assigned the overall responsibility for implementing theproject. The financing is managed by Stockholmsleder AB (owned byStatens Väg- och Baninvest AB, a company under the supervision of theMinistry of Industry, Employment and Communications) that raises loans onthe capital market and subsequently lends money to the Swedish NationalRoad Administration as works progress, in compliance with the guaranteeframeworks laid down by Parliament and the government. Repayment of theloans will begin once Södra Länken is opened to traffic.

Length of Södra Länken 6 kmLength of tunnels including ramps 17 kmTotal rock excavation 2 035 000 m3

Total soils excavation 747 000 m3

Total volume of concrete 225 000 m3

Reinforcement 14 500 tonnesPaved surface 280 000 m2

Lateral safety barriers 27 500 mSuspended ceiling 100 000 m2

Height of ventilation towersat Åbyvägen and Hammarby Fabriksväg 20 mFans 170Excavation routes 70Substations 13

Maximum speed limit, tunnels and most 70 km/haccess and exit rampsLane width 3.5 mShoulder width 1 and 2 m respectivelyMaximum vehicle height 4.5 mClearance under signs and fans 4.8 m

Traffic prior to Södra Länken after opened to trafficHuddingevägen AADT 45 000 AADT 11 250Hammarby Fabriksväg AADT 35 000 AADT 17 000Nynäsvägen AADT 90 000 AADT 70 000Årstalänken AADT 40 000 0 east of ÅbyvägenVärmdöleden AADT 50 000 AADT 30 000

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2 Södra Länken– a new traffic routein Stockholm

Stockholm RegionSE 171 90 Solna, Sweden

Telephone + 46 8 757 66 00E-mail: vagverket.sto@vv.se

www.vv.se • www.sodralanken.nu

Long traffic queues on city access roads, overfull parkand ride lots and crowded on the Stockholm Metro. Fordecades, this has been what it looks like in and aroundStockholm at rush hour. Prognoses indicate that thealready heavily overloaded traffic system in Stockholmmust make room for even more road users. In its forecastfrom 2000, the Swedish Institute for Transport andCommunications Analysis (SIKA) showed that roadtraffic was expected to increase by 25 percent by the year2010. The reason for the growing traffic volume is thatStockholm is becoming all the more attractive as a placeto live and work. The Regional Planning Office at theCounty Council estimated a population growth of20 000 per year between 2000 and 2030. This all

represents people who will be living in Stockholm andtravelling to their schools, jobs and recreational activities.

The construction of the completely new city quarterat Hammarby Sjöstad is one way to accommodate theincrease in population. Some 25 000 people will beliving, and 5 000 working here. Additional buildingdevelopments are being planned in Stockholm County,and transportation opportunities are decisive in wherethese can be located. The politicians in the 26 munici-palities comprising Stockholm County are working onsolving housing and transport issues.

The Dennis AgreementIn 1992, a political agreement known as the DennisAgreement was drawn up for the transport system inStockholm County. As far as road traffic was concerned,this meant that Essingeleden would be supplementedwith Norra Länken, Österleden and Södra Länken andtogether function as a ring around Stockholm. In 1997,the coalition behind the Dennis Agreement collapsed.Södra Länken is one of the projects that had progressedfar enough along that construction could begin. Amongthe other projects in central Stockholm that werelaunched and implemented, the light rail line and thetrunk bus route network can be mentioned.

The ring road aroundStockholm inner city,according to the plans in theDennis Agreement.

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4

Södra Länken – a newunderground road system

Södra Länken is a new road traffic system that linksEssingeleden, Huddingevägen, Nynäsvägen and Värmdö-leden. It is some 6 kilometres long, of which 4.5 kilome-tres run through tunnels under suburbs immediatelysouth of Stockholm’s inner city. Södra Länken isSweden’s largest road tunnel construction ever and themost extensive road project undertaken in the Stockholmregion since Essingeleden was built in the 1960’s. Thishighly sophisticated road system also includes inter-changes above ground at Åbyvägen, Årsta, Johanneshov,Nynäsvägen, Hammarby, Sickla and Värmdöleden.

Better flow in trafficSödra Länken is part of the national road network and isdesigned as an urban motorway with a speed of 70 km/h.On some of the access and exit ramps the speed islimited to 50 km/h. Södra Länken helps reduce throughtraffic in the inner city areas by offering a smooth andeasy alternative. Further, Södra Länken replaces the cross

route to the E4/E20 European Highways via HammarbyFabriksväg, Gullmarsplan, Huddingevägen and Årsta-länken on the southern periphery of the city. The unin-terrupted traffic flow due to the absence of intersectionsmeans a reduction in travel time across the entire stretchat rush hour from about 35 to about 5 minutes.

Södra Länken connects Värmdöleden with Essinge-leden and Södertäljevägen, linking the road networks inNacka, Värmdö and the southern city suburbs with otherroad networks in the region.

Traffic below ground improves the localenvironmentThe living environment along Nynäsvägen by theStockholm Globe and Johanneshovsvägen (formerlyHuddingevägen) is also much better. Residents, driversand public transport all benefit, and conditions arecreated for building residential and business develop-ments like Hammarby Sjöstad and Sickla. In 2004, when

5

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1960 ’sThe c i t y t r an spo r t p lan d rawn up i n 1960re su l t ed i n t he con s t r u c t i on o f E s s i nge l eden . Th i sp lan a l so i nc l uded Söd ra Länken a long ana l i gnmen t above g round . Bo t h we re i nc l uded i nt he p lan s f o r a r i ng road a round S tockho lm .

1988Dec i s i on t o l oca t e Söd ra Länken i n a t unne l .

1990 and 1992S ign i ng o f t he Denn i s Ag reemen t , wh i ch i n -c l uded Söd ra Länken .

1993De ta i l de s ign f o r t oday ’s Söd ra Länken i n i t i a t ed .

1997Cons t r u c t i on begun on Söd ra Länken .

1998F i r s t b l a s t i ng f o r t he Söd ra Länken ma in t u nne l si n Decembe r.

2004Söd ra Länken opened t o t r a f f i c .

Södra Länken is expected to be completed, about 60 000vehicles a day will be able to drive through the tunnels.Moving through traffic underground improves theenvironment in Årsta, Johanneshov and Hammarby-höjden.

Safer for pedestrians, cyclists and driversSödra Länken entails better road safety for all categoriesof road user. Pedestrians and cyclists can move aroundmore safely on local roads in the southern suburbs oncethrough traffic has disappeared, and driving is safer inthe tunnels where traffic lanes run through parallel tubeswithout on-coming traffic.

To the left: Södra Länkenimproves communications inthe southern suburbs, whichis a prerequisite for buildingnew residential and businessdevelopments like HammarbySjöstad and Sickla.

Map: Södra Länken is a newroad traffic system that linksEssingeleden, Huddinge-vägen, Nynäsvägen andVärmdöleden..

6

7

Advanced tunnelengineering techniques

Stockholm is largely built on bedrock. Below ground isan extensive system of tunnels for distance heating,sewage treatment, stormwater, telecommunications, theStockholm Metro, etc. There is also space here to moveroad traffic down into tunnels, and thereby protect thenatural environment and buildings above ground.

Södra Länken extends from the wholesale markets inÅrsta through tunnels under Årsta, Johanneshov andHammarbyhöjden. From there it crosses the Sickla Canalover a low bridge and continues on through tunnels toVärmdöleden. Along large parts of this alignment thetunnels have been blasted through the rock. Concretetunnels have been built on the stretches without suffi-cient rock cover, for example at tunnel mouths. Accesses

to the Södra Länken tunnels are located at Huddingevägen,Nynäsvägen, Gullmarsplan and Hammarby Sjöstad.

Tunnel blasted through rockStockholm’s new tunnels were blasted using moderntunnelling technology. Careful, controlled blastingmethods were applied at places where Södra Länkencrosses other tunnels as well as at sensitive environmentsby tunnel mouths.

The Stockholm bedrock is mostly compact andimpermeable. However, to avoid any groundwater drain-age and the consequential threat to vegetation andbuildings, the rock was sealed by grouting (see below).This ensured compliance with the provisions of the Water

8

Rights Court concerning sealed tunnels. The ground-water table will continue to be carefully monitored oncethe tunnel system is in operation.

Concrete tunnels and tunnel mouthsConcrete tunnels have been constructed at such places asÅbyvägen, Huddingevägen, Gullmarsplan and Nynäs-vägen. This is necessary where the rock cover is eithervery slight or non-existent. Structural engineering differsfor rock and concrete tunnels. Concrete tunnels requirespecialist knowledge about groundwater, how it isaffected as well as the effect it has in turn. Considerationhas been given to leakage, pressure and the water table:the tunnels are sealed to prevent groundwater fromleaking in. A lowering of the groundwater table must beavoided so as not to risk settlement of nearby buildings.

Two of the largest concrete tunnel constructions onSödra Länken can be found on Åbyvägen and Nynäs-vägen. The construction of the tunnel at Åbyvägenentailed the excavation of a 500 metre long and 50 metrewide section of Årstafältet immediately adjacent to high-rise buildings. Subsequent to this, the tunnel was cons-tructed in such a way as to ensure that the groundwaterwas not affected more than what is legally permissible.The tunnels at Nynäsvägen were also constructed under

Blasting procedure for the Södra Länkenrock tunnels:

1 Holes 20-26 metres long are drilled around what will be thefuture tunnel and subsequently filled with cement under highpressure (grouting). This is done to seal possible cracks in therock and prevent any groundwater leakage.

2 4-5 metre long holes are drilled.

3 These holes are loaded with explosives, and the blasting isdone under controlled conditions to limit vibration anddamage to buildings.

4 The blasted material is transported out of the tunnel.

5 Any rock left hanging around the tunnel cavity is knockedloose (scaling) after which the rock surface is reinforced withshotcrete and rock bolts as necessary.

Steps 1-5 were repeated over and over again until the tunnelblasting was completed in the summer of 2001

9

extremely complex technical conditions. The groundthere consists of esker, which is easier to work with andless prone to settlement than the clay on Årstafältet. Onthe other hand, at Nynäsvägen enormous demands wereplaced on managing a daily traffic volume of almost100 000 vehicles, complicated by the immediate prox-imity of buildings. The works were conducted as close asthree metres away from buildings.

Empty tunnels filled with fittings, fixturesand installationsOnce all the tunnels have been blasted or cast andinterconnect to form a continuous system, it is time forthe interior fittings and installations. The suspendedceiling, light fittings, collision protection barriers and thecarriageway are just a few of the important interiordetails. Apart from this, a great number of cables andsystems must be installed (see facts and information boxbelow). The installations and interior design works for atunnel system like Södra Länken are extensive andrequire careful planning, co-ordination and monitoring

Basic instal lat ions:

VentilationWaterWastewaterDrainageElectrical and control systemsLighting

Insta l lat ions for t raf f i cmanagement:

Route guidance signsLane signalsTraffic and incident detectionusing video camerasRoad closure barrier bars

to be able to function. Once the work has reachedcompletion, only a fraction of all the installations arevisible to road users. Most lie concealed in special recessesbehind the rock face.

Same official opening dayImproving road safety is one of the primary aims behindthe Södra Länken project. Driving in tunnels will besafer than driving the same stretch of road above ground.All the fittings and installations are designed to meetstringent safety regulations. The work on safety consid-erations includes a long breaking-in phase, and compre-hensive testing and evaluation will be conducted beforeopening Södra Länken to the public. Hence, no sub-stretch will be opened independently. The day when theSödra Länken tunnels are ultimately opened to traffic,everything will have been examined, tested and approved.

Insta l lat ions for tunnelsafety:

Tunnel information signsClose circuit TVRadio and mobile telephone networkEmergency telephone and push buttonsystemFire ventilationFire hydrants and empty pipes for fire-fighting waterManual fire extinguishersExplosion protection in the waste watersystemFireproof laying of cables for safety-related equipmentStand-by lightingGuide lighting and emergency exit signsEmergency equipment and rescue roomsEvacuation routes.

Farthest to the left:Concrete structures atNynäsvägen have beenconstructed underextremely complex trafficengineering conditions.

Closest to the left:Installation of the whiteceiling. Each elementweighs 4 tonnes.

10

Road tunnels inside a city, with underground access andexit ramps differ from normal tunnels on rural roads. Anurban tunnel system must be perceived by drivers as a safeand attractive choice of route where they find it easy toorient themselves. Hence, a high level of road safety, agood environment and good orientation facilities arecombined in Södra Länken. Architects, designers, instal-lation engineers and behavioural scientists all worked

Tunnels with spetogether to find solutions that satisfy both human needsand technical requirements.

Artistic design facilitates orientationIn order for people to find it attractive to drive downunderground, the tunnel environment must seem like partof the city above. This can be exemplified by the StockholmMetro, where art décor is a distinctive part of the system.

11

cial prerequisitesThose driving through the Södra Länken tunnels are able toorient themselves in a similar way. However, conditions aredifferent in the Metro where passengers experience most ofthe artistic decoration while waiting at the station. Drivers inSödra Länken will be travelling at a speed of about 20 metresper second, meaning that the artistic design will be experi-enced from a vehicle in motion. In this kind of environment,art becomes a matter of light, space and large-scale themes.

Obvious and safePeople feel comfortable when it is light and they can seewhere the road is heading. The road geometry on SödraLänken with its wide curve radii and few gradientsprovides good sight conditions. The white, light and airyceiling, which is found everywhere except in the cavernsat the access and exit ramps, hangs like a canopy high upabove the road. The slits between every white ceiling

12

module are intended to make the bends in the road evenclearer to the driver.

Signs installed in the tunnel ceiling forewarn driversabout each exit well ahead of time. There is also a motor-way control system, MCS, with variable message signs,which are used to inform drivers to slow down and keepon the alert. This can involve a closed exit, wherebydrivers will be guided to another, an obstruction block-ing the lane ahead, or a lower recommended speed dueto queue formations.

The tunnel walls consist largely of sprayed concreteover the rough rock surface, the varied texture of whichis experienced as a kind of ever-changing natural land-scape. This helps drivers judge distances, thereby impro-ving road safety.

Södra Länken’s wide curve radii make it easier for drivers to seewhere the road is heading.

Running along the walls are 160 centimetre highcollision protection concrete barriers. Any vehicle thatveers off the carriageway and crashes into these barrierswill be caught up and guided forward until coming to astop. Amber coloured vertical lines marked on thisconcrete barrier at ten metre intervals help drivers judgespeed and movement. Another regularly recurringfeature in the environment are the amber-colouredemergency exits with their distinctly prominent door-frames.

The light-coloured asphalt wearing course makes the3.5 metre wide lanes stand out against the darkerasphalt on the shoulders. It is also light-reflective, whichintensifies the lighting in the tunnel.

Throughout the entire tunnel system are longitudinal

13

white fluorescent strip lights to provide real colourreproduction. Extra lighting is provided at all the accessand exits. These automatically adjust to the level ofoutdoor light to provide a comfortable transition be-tween daylight and tunnel lighting.

Access and exits in specially designedrock cavernsThe 15 large caverns at the access and exits on SödraLänken are clearly recognisable places that create anatural division of the tunnel system into sub-stretches.The lighting is different than in the rest of the tunnelsystem and artistic design is used to individually identifyeach cavern. The idea is to break away from the whiteline of the suspended ceiling and alert drivers to therealisation that this is where they want to drive out ofSödra Länken. It also makes them more observant ofother vehicles entering the tunnel from the access ramp.

Safety provides securityThere is a high level of road safety all throughout SödraLänken. Drivers are encompassed by sensors that detectthe traffic rhythm as well as numerous other safetyinstallations. All electricity, ventilation, emergencyalarms, lighting etc are designed and protected to meetstringent safety regulations. Everything continues tofunction even in the event of a power failure or fire. The

wastewater system is also designed to be able to collectand purify both surface water and other liquids toprevent anything ecologically harmful from seeping outinto nature.

Södra Länken is also monitored through the trafficsurveillance system in Stockholm. This system is mannedaround the clock and alerted automatically if anythingdisrupts or stops traffic. Staff at ”Trafik Stockholm”, theTraffic Management Centre, can check what triggeredthe alert via a system of monitors. They can then dis-patch the police, rescue services or ”Road Assistance”vehicles as needed. The ”Road Assistance” team is onduty on weekdays to help keep traffic lanes free fromvehicles that have run into trouble or been involved inaccidents. They can also assist in evacuation and rescueoperations at accidents.

Emergency exit always close at handIn the event of an accident, it is easy for road users to getthemselves to safety. It is never more than 50 metres tothe closest emergency exit in the main tunnels, and nomore than 75 metres on the access and exit ramps. All inall, there are 70 clearly marked evacuation routes and140 emergency rooms with life-saving equipment andfire extinguishers. The safety concept also means thatthere is normally never any on-coming traffic in a tunneltube. Drivers travel through parallel tubes, one in each

Different artistic design makes exitseasy to recognise.

14

direction of travel. Should a major incident occur in oneof these, everyone can leave their vehicle and quicklymake their way to an amber-coloured emergency exit toget to the adjacent tunnel. This tunnel can also be usedto facilitate rescue services reaching the scene of theaccident.

If an accident involving a heavy build-up of smokeoccurs, jet fans come on automatically. Smoke andcombustion gases are ventilated out in the direction of

travel. Those road users who are behind the site of theaccident are supplied with fresh air, making it safe foreveryone to leave their vehicle to get to the closestemergency exit. In such an event, the parallel tunnel tubewill also be closed to traffic.

Equipment in the evacuation routes

Loudspeakers Emergency telephones

Fire extinguishers

Fire hydrants

Surveillance

Closed circuit television cameras as well as fire,

air pollution and traffic detectors

Emergency exit signsLoudspeakers in the evacuation routes

Evacuation routes across to the adjacent tunnel tube every 100-150 metres

Ventilation

Södra Länken is equipped with detectors that sense such things as smoke from a fire, air and traffic flow, etc.These, along with closed circuit TV, are used by the Traffic Management Centre to monitor tunnel safety around the clock.Traffic control is able to contact road users through a public address system, and can as necessary alert the "Road Assistance" team, the police, ambulances and the fire department.

15

Emergency exits with fire locksen route to the adjacenttunnels are located every100–150 metres. There arestations by these emergencyexits with emergencytelephones, fire extinguishers,loudspeakers, a supply of fire-fighting water, etc.

16

Light ceiling

Lighting

Emergency exits

Amber distancemarkers

Light-colouredasphalt

Rough texturerock wall

Collisionprotection

17

18

Fresh air in andaround the tunnels

Stringent demands have been placed on the air quality inSödra Länken. Levels of nitrogen dioxide and carbonmonoxide are monitored constantly from a total of 40meter points.

The air in Södra Länken is kept fresh through con-stant circulation. Vehicles pull fresh air along into thetunnels and take air mixed with emissions out withthem. The traffic in each tunnel tube only moves in onedirection, resulting in self-ventilation. The emissionscontent in the tunnel is monitored constantly. If thespeed of traffic decreases, making self-ventilation insuf-ficient, jet fans turn on automatically to get the aircirculation going.

Good air quality at all exitsNatural draught in the Södra Länken tunnels is veryeffective. This means that large amounts of exhaustfumes will be pushed to the tunnel mouths. Constantair quality control is therefore carried out there. If theemissions content on an exit ramp gets too high, freshair is pumped in by intake air fans to reduce the con-centration outside the exit.

Fan control centres with ventilation towers at themouths of the main tunnels help reduce the concentra-tion of vehicle emissions. A twenty-meter tall tower islocated at the western tunnel mouth at Årsta and at theeastern tunnel mouth at Sickla. The fan facilities are

19

used to suck up the air/exhaust fume mixture into theventilation towers for expulsion at high speed. Thoseliving close to the tunnel openings can feel secure. Theconcentration of nitrogen dioxide and carbon monoxidewill never be too high.

Furthest to the left: The tunnels are normally self-ventilating as a result of the movement of vehiclesthrough the tunnels. If the speed of traffic is reducedso that the draught becomes insufficient, jet fans turnon. It is expected that these fans, installed in thetunnel ceiling, will only be used in rare cases.

Closest to the left and below: The two twenty-metretall ventilation towers on Södra Länken areconstructed in glass and stainless steel. Eachventilation tower has a huge fan facility, whichnormally does not need to be taken into use.

Below to the right: Air intakes at ground level aresited at 15 places along Södra Länken. At these sitesfresh air is pumped into the system to dilute theemissions at the exit ramps and exits, and to cooldown the sub-stations and electricity distributioncentres underground. The air intake in the photo isabout three metres tall.

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Södra Länken– a distinctive part o

Södra Länken is an integral part of the road network in theStockholm region. Clearly identified accesses and tunnelentrances are therefore important. Anyone approachingSödra Länken must be able to understand that they are ontheir way into a tunnel system and where it is heading.

For those living and working in the vicinity, Södra

Länken will be an established feature in the local environ-ment. It is therefore essential that the architectural designof Södra Länken is well integrated in the environs.

Södra Länken is an extensive road tunnel system thatruns through vastly different environments, from the innerarchipelago by Värmdöleden, via the Nacka nature reserve

21

’s architectureof the city character

at Sickla to the densely populated residential suburbs atGullmarsplan, Johanneshov and Årsta. Several differenttypes of landscape with various considerations to buildingdevelopments and recreational areas are found here.Careful consideration has been given to the particularcharacteristics of each when designing the access ramps and

road stretches above ground. (This is described in moredetail on pages 22-31.) Tunnel entrances consist of every-thing from sunken placement below grade, such as atVärmdöleden and Nynäsvägen, to portals straight into therock wall, like at Sickla. The common denominator is that adistinctive portal is constructed around all tunnel entrances.

22

Södra Länken connects toEssingeleden in the west

Södra Länken consists of both tunnels, roads and accessroads of different kinds. Farthest to the west, SödraLänken connects to Essingeleden and the E4/E20. As aresult of traffic disappearing down into the Södra Länkentunnels, it became possible to completely take away thepart of Årstalänken east of Åbyvägen. This improvesaccessibility to green areas for those living in Årsta.

A somewhat sunken access to Södra Lännken and anew interchange have been constructed. This interchangemeans that the old bridge across Årstalänken at Åby-vägen has been replaced by a modern roundabout andthat new access roads have been provided for local traffic.The land around the interchange and the tunnel mouth

is designed with rock walls and groves of trees to emulateenclosed fields. Gravel, boulders, trees and bushes havebeen used to accentuate this theme.

Distinctive portalImmediately east of the Åbyvägen interchange, the roadbegins its descent towards the entrance to the SödraLänken tunnel system. The adjacent retaining walls arecovered with structural concrete to prevent groundwaterpenetration, and designed with horizontal bands inlaidwith coloured stone. The transition to the actual road-way consists of a raised granite curb.

Closest to the right: Tunnel mouth atÅrstafältet. One of Södra Länken’s twoventilation towers can be seen in thebackground.

Farthest to the right: Road safety andmobility on Huddingevägen has beenimproved.

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As for all the Södra Länken tunnel entrances, stainedconcrete has been used on the approach at Årstafältet.Above the tunnel opening is a fan building for the tunneltraffic and one of the two ventilation towers on SödraLänken. The roof of the fan building is covered invegetation to help it blend into the greenery of thesurroundings. The 20 metre tall tower is designed in glassand steel.

Concrete tunnel built under the open fieldImmediately inside Södra Länken’s western entrance is atunnel some 450 metres long. Constructing tunnels inthe clay earth on Årstafältet without affecting the

groundwater table more than permitted necessitatedhighly advanced engineering technology. The excavationfor the tunnel construction required good stabilisationusing sheet piling before the tunnel could be cast. After-wards, the excavation was re-filled and the groundlandscaped.

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That Södra Länken reduces the amount of throughtraffic in Stockholm’s southern suburbs is particularlyevident in Årsta, in the vicinity of the former Huddinge-vägen. Of the almost 45 000 vehicles passing throughevery day, 30 000 now drive down into the tunnels. Thismeans an enormous reduction in the noise from traffic.Air pollution is also reduced through directing trafficdown into Södra Länken where it can flow freely. Theremaining traffic on Huddingevägen no longer requiresas many traffic lanes. For the section between Årstafältet(where traffic on Huddingevägen has been providedanother entrance to Södra Länken) and the viaduct atGullmarsvägen, the former four traffic lanes can bereduced to two. This minimises the predominance of

Huddingevägen in Årsta’s residential area and providesmore safe space for pedestrians and cyclists.

The Johanneshov interchange links SödraLänken with GullmarsplanSome of the traffic on Södra Länken emerges intodaylight at the re-constructed interchange at Johannes-hov and continues on to Gullmarsplan. The actualopenings are located about 150 metres west of theroundabout at Gullmarsplan. On a stretch of about 350metres between Gullmarsvägen and Gullmarsplan,Huddingevägen has been upgraded from two to fourtraffic lanes. This has meant that the actual road reserve

Huddingevägen –Johanneshovsvägen

Immediately to the right: Tunnelentrance at Johanneshovsvägen.

Further to the right: Road safety andmobility on Huddingevägen has beenimproved.

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has been widened and lies closer to the buildings alongthe road. A high retaining wall has been built on thenorth side, where the Gullmarsplan upper secondaryschool is situated. One of the traffic lanes on Huddinge-vägen that takes local traffic through Årsta runs alongsidethis retaining wall. In the middle of the road are the twolanes that lead to and from the Södra Länken tunnels.South of this is the traffic lane for local traffic from Årstatowards Gullmarsplan, which has been placed over thetunnel entrances. Trees and other vegetation have beenplanted on the ground above the tunnels.

Design adapted to the environmentCareful attention has also been paid at this access andexit to making it clearly apparent that this is part ofSödra Länken. The distinctive tunnel structure is, likethe retaining wall at Gullmarsplan upper secondaryschool, covered in natural stone and blends in well withthe surroundings. The tunnel portal is designed instained light-grey concrete. The retaining walls andseparation wall between the carriageways have horizontalbands with inlaid coloured stones.

Huddingevägen south of the Södra LänkentunnelsSödra Länken’s southern exit and access to Huddinge-vägen is housed in a 350-metre long concrete tunnel.South of that, Huddingevägen has been given a newalignment: it has been straightened and moved eastwardsbetween its intersection with Sandfjärdsgatan/Älvkälle-vägen and Huddingevägen/Östebergavägen/Sockenvägen.It has also been widened and given two traffic lanes ineach direction. Moving the road has improved conditionsfor local residents and allowed Årstafältet to expandeastwards and become one large coherent green area(read more about this on page 22 ”Södra Länken con-nects to Essingeleden in the west”).

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Major changes atNynäsvägen

Nynäsvägen, with its near 100 000 vehicles a day, is oneof Stockholm’s most heavily trafficked access roads.Södra Länken will receive 20 000 of these vehicles andthereby lessen the burden on both Nynäsvägen and theroads feeding on to Huddingevägen and Essingeleden:Arenavägen/Palmfeltsvägen/Bolidenvägen.

At the Stockholm Globe Arena, some 1 500 metres ofNynäsvägen has seen substantial environmental changes.Its alignment has been lowered on the part between theSouthern Stadium and the intersection at Enskedevägen/Sofielundsvägen. At its lowest point at Enskedevägen/Sofielundsvägen, it is as much as eight metres below itsformer level. This has made it possible to reconstruct the

interchange at Sofielundsplan. Local traffic has beenmoved up onto a newly constructed roundabout withramps connecting down to Nynäsvägen, where themouths of the Södra Länken tunnels have been located.Local traffic now crosses the throughway above it. Noiselevels have been reduced by up to ten decibels, whichseems like it has been cut in half.

Better flow for all road user categoriesTraffic from Arenavägen out onto Enskedevägen has seenthe traffic lights replaced by a roundabout. Runningparallel to Nynäsvägen on its western side from theGlobe Hotel southwards is a new pedestrian and cycle

Closest to the right: Nynäsvägen hasbeen lowered about 5-8 meters from theSouthern Stadium to the intersection atEnskedevägen/Sofielundsvägen.

Farthest to the right: The deck coveringNynäsvägen at the Globe is 40 metreswide and has space for pedestrian andcycle traffic as well as landscaped areas.

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path that crosses Enskedevägen via an underpass andconnects to local streets west of Nynäsvägen. The round-about at Enskedevägen/Sofielundsvägen has a separatebridge for pedestrian and cycle traffic crossing Nynäs-vägen. At the Globe Arena, Nynäsvägen has been coveredby a 40 metre wide deck with landscaped trees. This”pedestrian mall” provides a better link between Skärmar-brink and the area around the Globe. The entire areaaround Nynäsvägen and its access roads is framed bylandscaped areas.

The traffic environment at Nynäsvägen along with itsfeeder roads is well nuanced. The design of the wideoverpass with a pedestrian and cycle path at the Globe

blends well into the surroundings with its white concreteand yellow glazed clinkers.

The interchange at Enskedevägen/Sofielundsvägenhas in part been cast with rippled profiles in a reddishbrown hue edged by a cobalt-blue clinkers profile thatalso runs horizontally. Below this are more sparselyplaced fields cast in natural concrete. The tunnel mouthsare marked by portals in light-coloured concrete.

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Södra Länken connects toVärmdöleden in the east

Södra Länken has meant major changes in the areabetween Sickla and Värmdöleden. It gives HammarbySjöstad a natural connection to the traffic system aroundStockholm, and those travelling from Nacka and Värmdötowards Essingeleden or the E4/E20 no longer need towait in queues around the Lugnet interchange and crowdtogether with some 40 000 other vehicles per day onHammarby Fabriksväg.

25 000 new residents and 5 000 new places of workin Hammarby Sjöstad entails the need for effectivecommunication links, which has resulted in its ownaccess and exits to Södra Länken. Somewhat further eastare the mouths of the main tunnel, after which traffic

continues on the sunken road towards the Sickla Canal.The number of lanes has been doubled to four on thisstretch. Between the tunnel entrance and the canal, a 40metre wide bridge has been constructed over the roadand covered with trees, shrubs and grass, a so-calledecoduct. It also accommodates a local street and pedes-trian/cycle path. The idea was to link Hammarby Sjöstadwith the Nacka Reserve on the other side of SödraLänken. This verdant bridge allows unobstructed move-ment for people and wildlife animals alike over thehighway.

Closest to the right: At HammarbyFabriksväg people and wildlife animalscan cross Södra Länken on two widebridges covered with trees, shrubs andgrass, a so-called ecoduct.

Furthest to the right: New interchange atSickla.

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New bridges and locks at Sickla CanalOn the other side of the ecoduct the road runs on newbridges across Sickla Canal. Here, the lowering of Ham-marby Fabriksväg has entailed building new bridges andthe addition of another lock for recreational boats. Inorder to protect fish, the new lock has been designedwith a salmon ladder.

Past the Sickla Canal, Södra Länken runs underanother ecoduct, 20 metres wide, and continues ontowards the new interchange at Sickla, where a round-about above the highway has replaced the former inter-section at Järlaleden for traffic connecting to and fromÄlta.

Strict requirements on environmentalconsiderationsThe entire stretch at Sickla is designed to blend into thesurrounding environment and reduce the noise oftraffic. The tunnel mouth at Hammarby Fabriksväg islocated at the foot of the ski hill. Rising above thetunnel mouth is one of Södra Länken’s two 20-metrehigh ventilation towers designed in glass and steel. Thetunnel mouth is designed with open arches in a façadeshield that is angled outwards at the ends. The entirefaçade is cast in light-grey concrete dotted with core cut-outs.

The carriageways are edged by granite barriers, with

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landscaped central reserves and roadside areas. The roadalignment has been lowered and the retaining wallsalongside have a facing of red Älvdalen quartzite. Glassshields have been installed for extra noise protection oncertain parts, like on the bridges over the Canal.

Eastern end of Södra LänkenPast Sickla, Södra Länken continues in tunnels underNobelberget, and opens directly out onto Värmdöleden.Over a distance of 600 metres the carriageways onVärmdöleden diverge, in between which Södra Länkenconnects with two lanes in each direction. The continua-tion of Värmdöleden towards the Lugnet interchange hasbeen reduced to two lanes in each direction for cars, witha lane reserved for buses towards the city.

The land around Värmdöleden lies adjacent to theinner archipelago. Here is Svindersviken bay and thenatural rock face of Nobelberget. The grey concrete

Below: Södra Länken’s tunnel mouths atVärmdöleden are located in the so-called“Coffee Hill”.

To the right: The retaining walls at SicklaCanal have a facing of red Älvdalen quartzite.

The tunnel entrance at Hammarby Sjöstad iscast in light-grey concrete dotted with core cut-outs.

Salmon ladder at Sickla Canal.

Retaining walls at Värmdöleden are designedwith pillars similar to those at the Stadsgårdenrock face.

encased by landscaped vegetation on Södra Länken as itruns through the central reserve harmonises well withthis nature. The tunnel portals are of grey concretesurrounded by raw, grey rock. Along the descent, theconcrete has been designed with pillars similar to thosefound at the rock face along Stadsgården further intowards Stockholm.

The entire stretch from the entrance at HammarbySjöstad covers 1 400 metres. 600 of these are housed intunnels, with the rest on roads above ground.

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The environment duringthe construction period

Constructing Södra Länken directly under Stockholm’ssouthern suburbs has involved several kinds of environ-mental impact. The vibration noise from the drilling wastransmitted through the rock and buildings, blastingworks continued under a relatively long time, trucktransports removing excavated materials had to drivethrough local neighbourhoods, etc. In order to reduce thedisruption during the construction period, the SwedishNational Road Administration required all contractorsworking on any part of Södra Länken to follow control-lable routines, so-called environmental managementsystems. These specified permissible noise and vibrationlevels, the transport routes that could be used, the timesat which the works could be executed, etc.

Controlled work procedures made it possible to limitthe disruption for those living nearby. One example wasthat all transports were directed to four work tunnelsbuilt in areas where few people live. Another exampleinvolved the excavation works for the access and exit

ramps for Södra Länken. As these had to be built in themidst of housing developments, the Swedish NationalRoad Administration minimised disturbance throughusing the quietest methods possible.

Noise and vibration unavoidableThe drilling down in the tunnels generated noise. Thesound from the drilling machinery was transmittedthrough the air, and the sound produced by the steel bitsstriking against the rock was transmitted through thebedrock. This noise was reproduced in the structuralframework of the buildings above.

Blasting is another kind of sound that causes severaltypes of disturbance, partly at the actual detonation, andpartly as shock waves that carry vibrations. The SwedishNational Road Administration provided information onplanned blasting via a constantly updated call service.People who experienced the blasting as particularlyupsetting were offered the opportunity to borrow a

Closest: Minicall on loan to localresidents wishing to be forewarned of adetonation.

To the right: Parts of the Södra Länkenconstruction have been conducted underor close to buildings. The SwedishNational Road Administration hastherefore stipulated that contractors usethe quietest methods possible.

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“minicall” which emitted a warning signal 30 minutesahead of a detonation. Local residents were also offeredtemporary evacuation quarters.

The works on Södra Länken have also caused vibra-tion. Buildings around Södra Länken had their ownindividual maximum vibration limits, which weremonitored using automatic vibration meters. Thevibration limit values were calculated on the basis of thecondition of the specific building and its foundation. Allbuildings were inspected both before and after theblasting works.

The excavated rock was high quality road-buildingmaterial. For environmental reasons, contractors wereresponsible for making optimal re-use of this.

Groundwater table to remain constantThe protection of groundwater and keeping the watertable constant has been a key consideration throughoutthe project. A lowering of the water table can have a

negative impact on the surrounding natural environ-ment and nearby buildings. In the construction ofSödra Länken, the tunnels and other engineeringstructures were sealed to prevent water drainage, andwater infiltration methods were also employed to ensurea constant water table level. More than 200 ground-water pipes have been placed along Södra Länken tocontinuously measure the groundwater level.

Monitoring and controlStockholm City has specified limits for the maximumpermitted noise and vibration levels caused by construc-tion works. The Swedish National Road Administrationhas stipulated that all contractors must comply withapplicable laws and ordinances as concerns environ-mental impact. It regularly controlled and monitoredcontractors’ environmental endeavours.

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Information forall concerned

The time required to construct Södra Länken, Sweden’slargest road tunnel project throughout time, is sevenyears. Such an enormous project in an area that affectssome of Stockholm’s most heavily trafficked roads,which entailed a great many work sites and affectedabout 20 000 households, naturally gives rise to manyquestions. The construction of Södra Länken has been amajor element in the daily lives of drivers and localresidents alike.

The road tunnel project has demanded preciseinformation and a good dialogue with all concerned. Aconstruction project lasting such a long time becomespart of people’s everyday life. Information about howthe works were progressing, the disturbance that couldbe expected and how to contact the Swedish NationalRoad Administration was given top priority. Answeringconcrete questions about the traffic situation on Värm-döleden, Hammarby Fabriksväg, Nynäsvägen, Hud-dingevägen and Årstalänken has been an important goalin information routines.

Information channels for local residentsand road users• Information meetings for local residents once a month.• Fact sheets distributed to the households affected once

a month.• Telephone number for queries and complaints.• Telephone answering service with regularly up-dated

information on blasting times and sites.• Information tours in residential areas – wandering bus

exhibition manned by a public information officer.• Open house with information about the progression of

the tunnel works.• Traffic advisories via radio with continuous information

on current traffic diversions.• Website www.sodralanken.nu.• ”Aktuellt om Länken” – notices and supplements in daily

newspapers concerning traffic diversions, road andtunnel works and the significance of Södra Länken onceit is open to traffic.

• Progress reports on video – regular documentation ofhow the work at the Södra Länken work sites isprogressing.

• Brochures and fact sheets with information about theconstruction of the different connections to SödraLänken and certain specific areas.

Open house in the tunnels. Public information officer and exhibition bus.