ENGINEER - Vol. XXXXV, No. 01, pp. [page range], 2011 © The Institution of Engineers,

ENGINEER - Vol. XXXXV, No. 01, pp. [page range], 2011 ©ENGINEERENGINEE TheFuture InstitutionR - Vol. of XXXXV,XXXXVImpact Engineers, ,No. No. Sri01, 01, Lankapp. pp.on [25-38], [page range], 2012 2011 Town Traffic Flow and © The PedestrianInstitution of Engineers, SriSafety Lanka due to Southern Expressway and Future Impact on Maharagama Town Traffic Flow and FutureOuter Impact Circular on Maharagama Highway: Proposed Town Traffic Solutions Flow and Pedestrian Safety due to Southern Expressway and PedestrianOuterA. S. Circular Amarasinghe Safety Hdue, Aighway. I. toGurusinghe Southern: Proposed and K Expressway. S. Weerasekera Solutions and

Outer Circular Highway : Proposed Solutions Abstract: Maharagama town becomes severely congested due to traffic & pedestrian activities during

daytime. The A.absence S. Amarasinghe of proper road, shouldersA. I. Gurusinghe makes the pedestriansand K. S. enterWeerasekera the carriageway, which in turn creates aA. safety S. Amarasinghe hazard and results, A .in I. slowing Gurusinghe down vehicular and K. trS.affic. Weerasekera After the completion of the Abstract: Southern Maharagama Expressway town and Outerbecomes Circular severely Highway, congested it isd ueexpected to traffic that & pedestrianadditional activities traffic volume during in daytime.Abstract:Maharagama The Maharagama absence town area of town proper will becomes result road shouldersin severely traffic conge makescongestedstion the pedestriansanddue safetyto traffic situation enter & pedestrian the evencarriageway, worse. activities In which orderduring in to turndaytime.find creates a solution The a absencesafety for hazardthis of proper situation, and roadresults capacities shoulders in slowing of makesroads down the were vehicular pedestrians evaluated traffic. enter by Aftercompiling the carriageway,the completion data of whichvehicular of the in Southerturnflow, creates pedestriann Ex presswaya safety movements hazard and Outer and and results Circularother in supportive slowing Highway, down information it is vehicular expected of tr thatthataffic. area additional After for thepresent completion traffic condition volume of theand in MaharagamaSoutherfor yearn 2030 Expressway town (i.e. 20 area years and will from Outer result now) Circular in withtraffic Hdo congeighway, nothingstion itoption. isand expected safety situationthat additional even worse. traffic In volume order to in findMaharagama a solution town for thisarea situation, will result capacities in traffic of conge roadsstion were and evalu safetyated situation by compiling even worse.data of In vehicular order to flow,findAccording apedestrian solution to the for movements obtained this situation, field and data othercapacities, and supportive capacity of roads informationcalcu werelations, evalu ofallated that the byroadsarea compiling for in thispresent area data condition will of vehicular badly and fail forflow,to year cater pedestrian 2030 to (i.e.the movements20 future years traffic from and now) demand other with supportive (i.e.do nothing for year information option. 2030) unless of that some area drasticfor present improvements condition and are forconducted year 2030 immediately (i.e. 20 years. Alsofrom it now) was foundwith do that nothing even atoption. present, available pedestrian facilities were not According satisfactory to thein this obtained area, field and thedata rate, and of capacity accidents calcu werelations, high. all Hence the roads road in widths, this area number will badly of lanes, fail toAccordingwalkway cater to shoulders,tothe the future obtained and traffic pedestrianfield demand data, andcrossings (i.e. capacity for were year calcu designed 2030)lations, unless usingall the somethe roads US drastic in highway this area improvements capacity will badly manual arefail conductedtoto caterevaluate to immediately thethe above future conditions . trafficAlso it demandwas in foundthe zone (i.e. that . forAlso even year geometric at 2030)present, unlessdes availableigns some for pedestrianislands drastic were improvements facilities conducted were based not are satconductedonisfactory AUSTROADS immediately in this guides area,. Also and and theittemplates was rate found of. accidentsObjective that even ofwere at this present, high. study Henceavailable is to introduce road pedestrian widths, suitable numberfacilities layout ofwere plan lanes, not for walkwaysatMaharagamaisfactory shoulders, in townthis area, and area pedestrian and with the required rate crossings of road accidents were improvements, weredesigned high. using road Hence the signs, road US andhighway widths, pedestrian numbercapacity facilities ofmanual lanes, to towalkwayenhance evaluate shoulders, traffic the above flow andconditions an pedestriand pedestrian in the crossings zone safety. Also were for geometric futuredesigned operational des usingigns forthe islands conditionsUS highway were with conductedcapacity the Smanualo baseduthern ontoExpressway evaluateAUSTROADS the and above guidesOuter conditions Circularand templates inH ighwaythe .zone Objective in. Alsooperation geometricof this. study des isigns to introducefor islands suitable were conducted layout plan based for Maharagamaon AUSTROADS town guides area and with templates required. roadObjective improvements, of this study road is to signs, introduce and suitable pedestrian layout facilities plan for to enhanceMaharagamaKeywords: traffic M townaharagama flow area an d with Town pedestrian required Traffic, safety S roadouthern improvements,for E futurexpressway operational , road Outer signs, C conditionsircular and H pedestrianighway with the facilities Southern to Expresswayenhance traffic and Outer flow anCirculard pedestrian Highway safety in operation for future. operational conditions with the Southern Expressway and Outer Circular Highway in operation. Maharagama Town Traffic, Southern Expressway, Outer Circular Highway Keywords: 1. Introduction Keywords: Maharagama Town Traffic, Southern Expressway, Outer Circular Highway

Maharagama town is administered by the 1. Maharagama Introduction Urban Council and it’s situated 1.around Introduction A4 (High Level Road), about 15 km Maharagama away from the town centre is of administeredthe commercial by capital the MaharagamaMaharagamaColombo. Town Urban town Councilarea is administered governed and it’s situatedby the the aroundMaharagamaMaharagama A4 (H Urbanigh Urban Level Council Council Road), and and about it ’sis situated 15 around km awayaround1.245 from km A42 . the (H centreigh Level of the R oad),commercial about capital 15 km .away from the Town centre area of the governed commercial by capital the MaharagamaColombo.As Figure Town 1 Urban indicates, area Council t governedhe studyand is area by around thewas

1.2Maharagamaselected45 km2 .between Urban Maharagama Council and Bo- treeis aroundjunction Figure 1 - Location of the study area (Source: [7]) 1.2 45 km2. (A) to President’s junction (C) along As Figure 1 indicates, the study area was Old Road (distance of about 800m) and along selectedAs Figure between 1 indicates, Maharagama the studyBo-tree area junction was High Level Road (distance of 820m). Figure 1 - Location of the study area (Source: [7]) (A)selected to President between’s Maharagama College junction Bo-tree (C junction) along Administrative authority of these two main Figure 1 - Location of the study area (Source: [7]) Old Road (distance of about 800m) and along (A)roads to Presidentis the Road’s College Development junction Au (thority.C) along In A. S. Amarasinghe, BTech (Eng) (Hon) (OUSL), High Level Road (distance of 820m). Oldthe Rselectedoad (distance study of area about there 800m are) and four along main Department of Civil Engineering, The Open University AdministrativeHigh Level Rauthorityoad (distance of these oftwo 820mmain). of Sri Lanka three legged intersections. They are Bo-tree roadsAdministrativejunction is the (A),Road authority DevelopmentPamunuwa of these Aujunction thority.two main (B),In A.A. S. I. Amarasinghe, Gurusinghe, Undergraduate, BTech (Eng) (Hon) Department (OUSL), of Civil throadsPresidente selected is the’s Road studyCollege Development area junction there are (C) Au fourthority. and mainClock In DepartmentA.Engineering, S. Amarasinghe, of CivilThe Open Engineering, BTech University (Eng) The (Hon) of Open Sri (OUSL), Lanka. threethtowere selected leg junctionged studyintersections. (D) as area indicated there They arein Figure are four Bo 1 main-.tree Department of Civil Engineering, The Open University ofEng. Sri (Prof.)Lanka K. S. Weerasekera, BSc Eng (), junctionthree leg ged (A), intersections. Pamunuwa They junction are Bo - (B),tree A. MEngSc I. Gurusinghe, (UNSW), Undergraduate, PhD (UNSW), Department FIE (Sri Lanka of Civil), Presidentjunction ’s (A),College Pamunuwa junction (C) junction and Clock (B), Engineering, The Open University of Sri Lanka. A.CEng, I. Gurusinghe, IntPE(SL), MIEUndergraduate, (Aust), CPEng, Department MIHT (UK),of Civil towerPresident junction’s College (D) as indicated junction in (C) Figure and 1C. lock Engineering,MASCE, Professor The Open in Civil University Engineering, of Sri Lanka.Department of Eng. (Prof.) K. S. Weerasekera, BSc Eng (Moratuwa), tower junction (D) as indicated in Figure 1. MEngScEng.Civil (Prof.) Engineering, (UNSW), K. S. Weerasekera Ph TheD Open(UNSW), University, BScFIE Eng(S riof Lanka(Moratuwa),Sri Lanka), . CEng, IntPE(SL), MIE (Aust), CPEng, MIHT (UK), 1 MEngSc (UNSW), PhD (UNSW), FIE (Sri Lanka), MASCECEng, IntPE(SL),, Professor MIE in Civil (Aust), Engineering, CPEng, MIHT Department (UK), of CivilMASCE Engineering,, Professor The in Civil Open Engineering, University of Department Sri Lanka. of Civil Engineering, The Open University of Sri Lanka. 1

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The Colombo-Matara Highway (also known as congestion around Maharagama town will be the Southern Expressway) is partially worse in the future unless a proper solution is constructed at present. This will link the Sri given. Lankan capital Colombo with Matara, a major city in the south of the country. This 128 km Also the road shoulders in Maharagama town expressway once fully completed will be 26 m are often encroached by wayside traders, wide, (ie. Including 3 lanes each direction, hawkers & other businesses for private use. centre-median, and 2 emergency lanes on The absence of proper road shoulders makes either side). Initially it will have 4 lanes up to the pedestrians enter the carriageway, which in from Makumbura with the remainder turn creates another safety hazard and results having 2 lanes. The entire expressway will later in slowing down vehicular traffic. be widened to six lanes [1]. Maharagama roads within our study area do not have adequate road width even to allow Outer Circular Highway (OCH) is an access parking on one side of the road besides on both control road encircling Colombo. The 29 km sides. But haphazard and illegal parking is (18 mile) long Outer Circular Road will connect commonly contributing to traffic congestion in with proposed Colombo-Matara Expressway the area. and with proposed Colombo- Expressway (under construction) and will provide an orbital beltway to bypass the city of Colombo. On completion, this highway will provide access to existing national highways (i.e. A and B class roads) and proposed expressways at several interchanges, and as such will serve as the basis for the entire network of highways and expressways in the country [1]. The main objective of the Outer Circular Highway is to disperse traffic congestion and encourage development away from the highly populated urban areas in the western province achieving a better balance for physical and economic growth. Figure 2 – Makumbura interchange (Source: [1]) It is observed that during peak hours Maharagama town area gets severely congested due to traffic & pedestrian activities. 2. Aim and Objectives As a solution currently a one-way road system is introduced around Maharagama, but still the The Maharagama town area is already congested problem is not addressed completely. by traffic and pedestrian activities. One of the Therefore people waste time on the road which major problems for congestion at Maharagama they could use more productively when town is because of excessive pedestrian passing Maharagama town. movements taking place due to number of wayside textile traders occupying Maharagama Southern Expressway starts from Makumbura town area as their business grounds. Also this interchange which is located east of business community disturbs the walkways and town. This interchange is also a continuation of pedestrians have to use the carriageways for their Outer Circular Highway. After construction of movements. The obvious solution for this the Southern Expressway and Outer Circular situation is, to transfer this business activity away Highway, it can be expected to create a certain from the congested locations. Also unavailability volume of additional traffic to the High Level of a central stand is causing a major Road. Initially Southern Expressway will have transportation issue in Maharagama. This has four lanes but later will be expanded to six resulted in large amount of cross transfers across lanes which may influence to increase to a high the roads. In future, according to the normal level of traffic as mentioned above. Traffic that growth, the traffic volume will rapidly increase. travels along Outer Circular Highway and In addition, after the implementation of the Southern Expressway to Colombo and from Southern Expressway and Outer Circular Colombo to these highways has to pass Highway it can be expected to create a high through Maharagama town. Hence the traffic

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The Colombo-Matara Highway (also known as congestion around Maharagama town will be volume of additional traffic to the roads within the Southern Expressway) is partially worse in the future unless a proper solution is the study area. 3.2 Traffic and pedestrian studies constructed at present. This will link the Sri given. Following traffic data gathering exercises were Lankan capital Colombo with Matara, a major The aim of this study is to identify whether conducted. city in the south of the country. This 128 km Also the road shoulders in Maharagama town the existing road capacities are enough to cater expressway once fully completed will be 26 m are often encroached by wayside traders, to the current traffic volume and also for the Measure the volume of daily traffic flow wide, (ie. Including 3 lanes each direction, hawkers & other businesses for private use. future traffic. Then to Explore possibility to according to vehicle types on relevant roads centre-median, and 2 emergency lanes on The absence of proper road shoulders makes improve the roads by introducing suitable road in Maharagama. either side). Initially it will have 4 lanes up to the pedestrians enter the carriageway, which in widths and number of lanes at study area to Galle from Makumbura with the remainder turn creates another safety hazard and results cope with the traffic needs at a reasonable level Identification of peak flows. having 2 lanes. The entire expressway will later in slowing down vehicular traffic. of service, while enhancing the safety of Conduct turning movement surveys. be widened to six lanes [1]. Maharagama roads within our study area do pedestrians. not have adequate road width even to allow Conduct highway capacity analysis. Outer Circular Highway (OCH) is an access parking on one side of the road besides on both In achieving the above aim, there are some Carry out pedestrian volume surveys. control road encircling Colombo. The 29 km sides. But haphazard and illegal parking is interim objectives that have to be satisfied. (18 mile) long Outer Circular Road will connect commonly contributing to traffic congestion in Following concerns have been addressed in this Conduct pedestrian travel pattern studies. with proposed Colombo-Matara Expressway the area. study. and with proposed Colombo-Katunayake Expressway (under construction) and will 1. To check whether the road capacities are 3.3 Accident study provide an orbital beltway to bypass the city of adequate to cater to the current traffic Collect accident records from Maharagama Colombo. On completion, this highway will volume in Maharagama town area. Police Station. provide access to existing national highways (i.e. A and B class roads) and proposed 2. Design the roads in Maharagama town area Identify the high risk accident locations. (i.e. Black spots). expressways at several interchanges, and as for year 2030 with a suitable level of such will serve as the basis for the entire service to cater to normal & additional Ranking them using suitable network of highways and expressways in the traffic from Southern Expressway & Outer country [1]. The main objective of the Outer Circular Highway. method. Circular Highway is to disperse traffic Recommend proper treatments to those congestion and encourage development away 3. Design the islands by conducting turning accident prone locations. from the highly populated urban areas in the movement surveys at main intersections as western province achieving a better balance for an alternative method to improve and physical and economic growth. streamline the traffic flow. 3.4 Capacity checks Figure 2 – Makumbura interchange (Source: [1]) Highway capacity checks were conducted for It is observed that during peak hours 4. Design of pedestrian crossings & walkways High Level Road, Old Road, Road, Maharagama town area gets severely within the study area to suit the pedestrian and Pamunuwa Road for the present and congested due to traffic & pedestrian activities. 2. Aim and Objectives activity in the area. future traffic flows to check on their As a solution currently a one-way road system satisfactory performance. These roads were is introduced around Maharagama, but still the The Maharagama town area is already congested 5. Conduct an accident study in the specific evaluated to see whether they could carry the problem is not addressed completely. by traffic and pedestrian activities. One of the area and propose remedial measures by flows satisfactorily. During the study if found Therefore people waste time on the road which major problems for congestion at Maharagama identifying the black spots. that road widths and lanes do not satisfactorily they could use more productively when town is because of excessive pedestrian cater to the future traffic, they were redesigned passing Maharagama town. movements taking place due to number of 6. Prepare a suitable layout plan for using the highway capacity manual. wayside textile traders occupying Maharagama Maharagama town area which satisfies the Southern Expressway starts from Makumbura town area as their business grounds. Also this above requirements. Pedestrian data was obtained by conducting interchange which is located east of Kottawa business community disturbs the walkways and pedestrian surveys and analyzed these data to town. This interchange is also a continuation of pedestrians have to use the carriageways for their check the pedestrian safety with increasing

Outer Circular Highway. After construction of movements. The obvious solution for this population and traffic growth for year 2030. the Southern Expressway and Outer Circular situation is, to transfer this business activity away 3. Methodology Crosswalks and sidewalks were redesigned Highway, it can be expected to create a certain from the congested locations. Also unavailability after checking for population growth, since it volume of additional traffic to the High Level of a central bus stand is causing a major 3.1 Data from relevant institutions was found that present facilities and Road. Initially Southern Expressway will have transportation issue in Maharagama. This has Relevant data was collected from Urban conditions were not of acceptable standards. four lanes but later will be expanded to six resulted in large amount of cross transfers across Development Authority of Sri Lanka, Road Traffic and pedestrian islands were designed lanes which may influence to increase to a high the roads. In future, according to the normal Development Authority of Sri Lanka, to provide pedestrian safety and to minimize level of traffic as mentioned above. Traffic that growth, the traffic volume will rapidly increase. , Maharagama accidents in this study area. travels along Outer Circular Highway and In addition, after the implementation of the Police Station, Southern Transport Southern Expressway to Colombo and from Southern Expressway and Outer Circular Development Project, and Outer Circular Road Also field surveys were done to evaluate the Colombo to these highways has to pass Highway it can be expected to create a high Project. dimensions of roads and pedestrian crossings through Maharagama town. Hence the traffic

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within the study area at present. Furthermore foresee the traffic demand in another 15 to 20 turning movement surveys were carried out. years from now. This in turn helps to decide the highway capacity at a suitable level of service 4. Data and Analysis for the predicting time period.

4.1 Identification of peak hour Figure 4 indicates the peak hour traffic From the 24 hour MCC traffic data, morning, volumes that would be added to the High mid-day and evening peak hours within the Level Road due to the Southern Expressway study area were identified. There were two and Outer Circular Highway in year 2030 [4, major peak hour ranges; morning peak from 5]. Morning peak hour flows were taken 7.30 to 8.30 am and the evening peak from towards Colombo direction and evening peak 17.30 to 18.30 pm. Since, Maharagama town hour flows were taken in the opposite area experienced heavy traffic (both vehicular direction. and pedestrian) during mid-day, the field studies were also focused during the day time too.

4.2 Distance between intersections and pedestrian crossings. Distances between intersections and crossings were measured and are indicated in Figure 3 below.

Figure 4 –Peak hour flows in Makumbura interchange at year 2030

Figure 3 - Locations of pedestrian crossings. Traffic volume forecast for year 2030 at Makumbura interchange (without the two new roads) was computed with equation 4.3 Pedestrian volume shown below [4]. Pedestrian surveys were conducted at 75m n stretches. Pedestrian crossings taking place (in (PHV)future (PHV)present (1 g ) both directions) at 5 minute intervals were recorded separately on High Level Road, Old PHV = Peak Hour Volume Road, Dehiwala Road, and Pamunuwa Road g = Annual growth factor. within the study area. This gave us a good insight of the pedestrian crossings taking place n = Number of years in the study area and a basis to design the proposed pedestrian crossings. The additional traffic from the two new roads was then taken into consideration in obtaining 4.4 Accident data the new volumes. Finally total volumes were The police usually maintain daily accident computed. records. It contains the date, time, location, nature of accident and elements involved. Three 4.6 Capacity analysis. natures of accidents were categorized as; Fatal, Road capacity checks were carried-out for the Grievous, and Light. Data within four years High Level Road, Old Road, Pamunuwa Road and (from 2007 onwards) was collected. Dehiwala Road using US highway capacity manual [7]. Level of services for each road 4.5 The traffic volume forecast segments were checked for existing traffic Using the present traffic volumes and relevant conditions. Initially capacities were checked for growth factors obtained from RDA future traffic current traffic condition in above four roads. Then in the study area was computed. This helped to it will be continued for High Level Road and Old

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within the study area at present. Furthermore foresee the traffic demand in another 15 to 20 Road, considering both normal traffic and cj = Capacity per lane for a multilane turning movement surveys were carried out. years from now. This in turn helps to decide the additional traffic from Southern Expressway and highway with design speed J: 2000 highway capacity at a suitable level of service Outer Circular Highway in year 2030. pcphpl for j = 70mph or 60mph, 1900 4. Data and Analysis for the predicting time period. pcphpl for j = 50mph 4.7 Design of road widths and introduction of 4.1 Identification of peak hour Figure 4 indicates the peak hour traffic additional lanes N = Number of lanes in one direction volumes that would be added to the High From the 24 hour MCC traffic data, morning, From the above capacity analysis results, by Level Road due to the Southern Expressway considering impact of traffic from Southern mid-day and evening peak hours within the (v/c)i = Maximum volume-to-capacity ratio and Outer Circular Highway in year 2030 [4, study area were identified. There were two Expressway and Outer Circular Highway, it was allowable while maintaining the 5]. Morning peak hour flows were taken proposed to improve the study area roads by major peak hour ranges; morning peak from performance characteristics of LOSi towards Colombo direction and evening peak 7.30 to 8.30 am and the evening peak from introducing suitable road widths and sufficient hour flows were taken in the opposite 17.30 to 18.30 pm. Since, Maharagama town number of lanes to cope with the traffic needs at a fw = Adjustment factor for lane width direction. area experienced heavy traffic (both vehicular meaningful level of service. and pedestrian) during mid-day, the field fHV = Adjustment factor for the presence of studies were also focused during the day time 4.8 Level of service criteria heavy vehicles in the traffic stream too. Level of service criteria for multilane and two lane highways are defined in terms of density [5]. fE = Adjustment factor for the development 4.2 Distance between intersections and Complete Level of Service (LOS) criteria are given environment and type of multilane in pedestrian crossings. in US highway capacity manual for 70mph, 60mph the traffic stream Distances between intersections and crossings and 50mph design speed elements. That gives the were measured and are indicated in Figure 3 average travel speed, the maximum service flow fP = Adjustment factor for driver below. rate, Maximum Servoce Flow, for each level of population service. The maximum service flow rates are stated in terms of rates of flow for the peak 15 min. 4.10 Capacity analysis for present condition Demand or forecasted volumes will be divided by of Old Road with normal traffic and the peak hour factor to reflect a maximum flow rate. additional traffic at year 2030 High-level Road, Old Road and Dehiwala Road will Road width = 34ft(10.36m)

be considered as multilane highways and Shoulder width = 4.27ft (1.3m) Figure 4 –Peak hour flows in Makumbura Pamunuwa Road is the two lane highway. In this No of lanes = 3 interchange at year 2030 study, for capacity analysis both of the above Full hour volume = 4092vph mentioned criteria were used [5].

Traffic volume forecast for year 2030 at Maximum 15 min volume = 1138vph Figure 3 - Locations of pedestrian crossings. 4.9 Capacity analysis of the Old Road Makumbura interchange (without the two (multilane highway) Lane width = (34ft/3) = new roads) was computed with equation shown below [4]. Old Road in Maharagama town area was 11.33ft (3.45m) 4.3 Pedestrian volume Peak hour factor = (full hour Pedestrian surveys were conducted at 75m considered as a multilane highway, and capacity n volume/4 × Maximum 15 min volume) stretches. Pedestrian crossings taking place (in (PHV) (PHV) (1 g ) checks were conducted as per US highway capacity future present manual (1985) [5]. Service flow rate = Full hour both directions) at 5 minute intervals were volume/Peak hour factor = 4092/ (4092/4 × recorded separately on High Level Road, Old PHV = Peak Hour Volume 1138) = 4552 vph SFi = MSFi × N × fw × fHV × f E × fP Road, Dehiwala Road, and Pamunuwa Road g = Annual growth factor. within the study area. This gave us a good When using the US highway capacity manual n = Number of years MSFi = cj × (v/c) i insight of the pedestrian crossings taking place for capacity calculation it takes care of several in the study area and a basis to design the adjustment factors, such as; lane width or proposed pedestrian crossings. The additional traffic from the two new roads SFi = cj × (v/c) i × N × fw × fHV × fE × fP lateral clearence restrictions (fw), presence of was then taken into consideration in obtaining the new volumes. Finally total volumes were heavy vehicles in the traffic stream (fHV), 4.4 Accident data environment and type of the multilane The police usually maintain daily accident computed. SFi = Service flow rate; the maximum flow highways (fE), and driver population (fP) which records. It contains the date, time, location, rate that can be accommodated by are affected by prevailing conditions that are nature of accident and elements involved. Three 4.6 Capacity analysis. the multilane highway, in one Road capacity checks were carried-out for the direction, under prevailing roadway not ‘ideal’. natures of accidents were categorized as; Fatal, Grievous, and Light. Data within four years High Level Road, Old Road, Pamunuwa Road and and traffic conditions, while meeting fw = 0.961 (by linear interpolation) Dehiwala Road using US highway capacity the performance criteria of LOSi in vph (from 2007 onwards) was collected. manual [7]. Level of services for each road Consider commuter and regular users. 4.5 The traffic volume forecast segments were checked for existing traffic MSFi = Maximum service flow rate; the maximum rate of flow which can fp = 1.00 Using the present traffic volumes and relevant conditions. Initially capacities were checked for be accommodated by the growth factors obtained from RDA future traffic current traffic condition in above four roads. Then multilane highway segment. Multilane highway is undivided and suburban in the study area was computed. This helped to it will be continued for High Level Road and Old fE = 0.8

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4.12 Capacity analysis of the Pamunuwa Computation for the heavy vehicle adjustment Road (two-lane, two–way highway) factor fhv was now carried out after Pamunuwa Road is the minor road segment in determining passenger car equivalent for Maharagama area and additional traffic from trucks (ET) and (EB) and also proportion Southern Expressway and Outer Circular of trucks and buses in the traffic stream which Highway does not directly impact on the road. were PT and PB. It is a two lane highway and necessary to do the capacity check on normal traffic growth for fHV = 1/{ 1 + PT ( ET -1) + PB ( EB-1) } 2030 year.

ET = 1.7, EB = 1.5, PT = 0.09, PB = 0.1, and Total two way hourly volume on Pamunuwa fHV = 0.898 Road was 1932 vph. Using the highway capacity manual taken the peak hour factor, v/c = SFi /cj × N × fw × fE × fp × fHV 1932 vph > 1900 vph. Hence peak hour factor was 0.96 cj = 2000 pcphpl. According to the turning movement survey v/c = 4552 / (2000×3×0.961×0.898×0.8×1) details, directional split of traffic on Pamunuwa Road was taken as 60/40. v/c = 1.09 Therefore adjustment factor for directional distribution fd was taken as 0.94 using US 1.09 volumes to capacity ratio belong to level highway capacity manual.Type of the terrain of service E. of Pamunuwa Road is level.

Hence present conditions of Old Road were Actual flow rate = peak hour volume / peak not satisfactory to cater the future traffic hour demand to maintaining level of service D. factor -- do -- = V/PHF 4.11 Redesign of Old Road with normal traffic and additional Actual flow rate = 1932 vph/0.96 traffic at year 2030 = 2013 vph Capacity analysis for Old Road, Directional split was 60/40. Hence total Considering morning peak hour (the worst scenario) capacity was 2300 pcph

SFi = 2650 × (v/c) × fw × fHV × fd Full hour volume = 4092 vph Full hour volume = 5013pcuph SFi (LOS A) =2650×0.15×0.937×0.829× 0.94 PT = 0.09, PB = 0.1, fHV = 0.898, fE = 0.8, SFi (LOS A) = 290 vph fP = 1.00 Using the same method, service flow rates were Design level of service is D, calculated for LOS B, C, D, E and tabulated v/c = 0.8 below. Design speed = 60mph (96.56kmph) MSFi = 1600 Table 1 – Service flow rates for different LOS Design lane width = 12ft (3.66m)

Design shoulder width = 6ft (1.82m) LOS v/c fw fhv fd SFI Hence fw = 1 (vph) SFi = 5013 pcu (Service A 0.15 0.937 0.829 0.94 290 flow rate on Old Road at year 2030) B 0.27 0.937 0.800 0.94 504 N = SFi / (MSFi × fw × fHV × fE × fP) C 0.43 0.937 0.800 0.94 803 N = 5013/ (1600 × 1 × 0.898 × 0.8 × 1) N = 4.36 D 0.64 0.937 0.829 0.94 1239

Designed no of lanes = 5 E 1.00 0.976 0.829 0.94 2015 Designed road width = 60ft (18.29m)

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4.12 Capacity analysis of the Pamunuwa When comparing these values with actual flow 4.14 Check pedestrian crossing time for Computation for the heavy vehicle adjustment Road (two-lane, two–way highway) rate of year 2030 value (2013vph) this value signalized pedestrian crossing factor fhv was now carried out after Pamunuwa Road is the minor road segment in was higher than the service flow rate for LOS When projected for a population growth rate of determining passenger car equivalent for Maharagama area and additional traffic from D. Hence road segment was not adequate to 1.4%, a zebra crossing will not be sufficient for trucks (ET) and buses (EB) and also proportion Southern Expressway and Outer Circular cater to the traffic demand in year 2030. Hence, the pedestrian volume in 2030 in front of the of trucks and buses in the traffic stream which Highway does not directly impact on the road. Pamunuwa Road also had to be designed as a super market. It exceeds the allowable width of were PT and PB. It is a two lane highway and necessary to do multilane highway. the zebra crossing. Therefore when considering the capacity check on normal traffic growth for pedestrian safety with vehicular growth and fHV = 1/{ 1 + PT ( ET -1) + PB ( EB-1) } 2030 year. 4.13 Analysis of pedestrian crossings (for population growth, its better to propose a year 2030) pelican crossing in front of the super market. ET = 1.7, EB = 1.5, PT = 0.09, PB = 0.1, and Total two way hourly volume on Pamunuwa All the crossings except the crossing in front of fHV = 0.898 Road was 1932 vph. Using the highway the supermarket were moderately affected due Minimum pedestrian green time required for capacity manual taken the peak hour factor, to vehicular traffic within peak hour. Hence in front of the super market is v/c = SFi /cj × N × fw × fE × fp × fHV 1932 vph > 1900 vph. Hence peak hour factor they were analyzed as zebra crossings for year was 0.96 2030. According to the pedestrian LOS criteria; GP = 3.2 + L/Sp + (2.7 Nped / WE) cj = 2000 pcphpl. designed level of service was taken as C [7]. WE > 10 ft (3.05m) [6] According to the turning movement survey v/c = 4552 / (2000×3×0.961×0.898×0.8×1) details, directional split of traffic on Sample calculation for pedestrian crossing near L = Width of the road Pamunuwa Road was taken as 60/40. temple road is stated below. In this calculation WE = Width of the crossing v/c = 1.09 Therefore adjustment factor for directional the highest pedestrian inbound volume and distribution fd was taken as 0.94 using US outbound volume were taken for year 2010 GP = Pedestrian green time. 1.09 volumes to capacity ratio belong to level highway capacity manual.Type of the terrain and extended to year 2030 volume using Sp = Pedestrian speed. of service E. of Pamunuwa Road is level. population growth factors. Nped = Number of pedestrian per second. Hence present conditions of Old Road were According to the pedestrian LOS criteria Actual flow rate = peak hour volume / peak not satisfactory to cater the future traffic hour demand to maintaining level of service D. factor Pedestrian space = 24 sq.ft/ped (from US L = 18.29m, Sp = 1.2ms-1, WE = 5m -- do -- = V/PHF highway capacity manual) GP = 3.2 + 18.29/1.2 + [(2.7 × 2) / 5] 4.11 Redesign of Old Road with GP = 19.52 s normal traffic and additional Actual flow rate = 1932 vph/0.96 Design width = (Pedestrian per min GP = 20 s traffic at year 2030 = 2013 vph ×Pedestrian space) /Crossing width Capacity analysis for Old Road, Directional split was 60/40. Hence total 4.15 Analysis of accident data Considering morning peak hour (the worst Sample calculation for pedestrian crossing near Accident data of four years (2007 to 2011) was scenario) capacity was 2300 pcph temple road, collected. Data on date of accident, time, location, elements involved and nature of SFi = 2650 × (v/c) × fw × fHV × fd Highest inbound and outbound volume for Full hour volume = 4092 vph 2010 (Vped 15min) = 313 accident were obtained. Locations were Full hour volume = 5013pcuph SFi (LOS A) =2650×0.15×0.937×0.829× 0.94 Highest inbound and outbound volume for selected from data which had more than three PT = 0.09, PB = 0.1, fHV = 0.898, fE = 0.8, accidents (ie. any type, either fatal, grievous or SFi (LOS A) = 290 vph 2030 (Vped 15min) = 414 fP = 1.00 Pedestrians per minute = 414/15 light) within four years. Those were identified Using the same method, service flow rates were = 28 ped/min as high risk accident locations. The distribution Design level of service is D, calculated for LOS B, C, D, E and tabulated of types of accidents is shown in Figure 5 and v/c = 0.8 below. According to the pedestrian LOS criteria [7] the collision diagram is shown in Figure 6. Design speed = 60mph (96.56kmph) Pedestrian space = 24 sqft/ped MSFi = 1600 Table 1 – Service flow rates for different LOS Design lane width = 12ft (3.66m) Design width = (Pedestrian per minute × FatalFatal 10 Design shoulder width = 6ft (1.82m) LOS v/c fw fhv fd SFI Pedestrian space)/ Crossing width) 10 Grevous Hence fw = 1 Designed width = 28×24/60 = 11.2ft (3.41m) s Grevous (vph) 8 nt SFi = 5013 pcu (Service A 0.15 0.937 0.829 0.94 290 Light de 6 Light flow rate on Old Road at year 2030) Pedestrian crossing in front of the supermarket ci B 0.27 0.937 0.800 0.94 504

greatly affected the vehicular traffic on High Ac 4 4 N = SFi / (MSFi × fw × fHV × fE × fP) Level Road and vehicular traffic from C 0.43 0.937 0.800 0.94 803 of 2 N = 5013/ (1600 × 1 × 0.898 × 0.8 × 1) Maharagama to Dehiwala. Also large numbers 2 No N = 4.36 D 0.64 0.937 0.829 0.94 1239 of pedestrian were using this pedestrian Accidentsof No 0 crossing. Hence it was decided to design it as a 1357911 Designed no of lanes = 5 E 1.00 0.976 0.829 0.94 2015 signalized pedestrian crossing. 1 3 5 7 9 11 Designed road width = 60ft (18.29m) LocationLocation

Figure 5 - Distribution of types of accidents

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When total accident weightage was greater than 15 it was taken as a black spot. Calculated weightages for each location were plotted and is shown in Figure 7.

TotaTotall weig weightagehtage of acci deofnt accidentss 45 45 40 4035

35e 30

ag 25 Total

30ht weightage 20 ig Total 2515 we weightag 2010 e 155 weightage 100 5 1234567 Figure 6 – Collision diagram Loca�on 0

4.16 Identification of black spots Figure 7- Accident1 2 weightage3 4 5for each6 location7 As per accident data from police records it was Location able to identify eleven high risk accident locations; which had more than three accidents Analysing the above accident data, the within four years in study area. Weightages following observations were made. were given to different types of accidents and calculated the total weightage of each Five fatal accidents had occurred within identified black spot locations and ranked four year period in this study area. them.

According to the gravity of accident category weightages of 5, 3 and 1 were assigned for Most of the accidents were vehicle to Fatal, Grievous and Light respectively [3]. vehicle and vehicle to pedestrian related.

P = X + 3 × Y + 5 × Z, where Most cases of pedestrians involving X = total number of light injuries accidents had happened due to haphazard Y = total number of grievous injuries crossing of roads. Z = total number of fatal injuries Pamunuwa Road junction was the major Table 2 – High-risk accident locations area prone to accidents.

No. Location Weightage According to the above observations vehicle accidents in Maharagama area was not due to 1 Pamunuwa Road junction (39) high speed driving of vehicles but due to 2 Old Road 138 bus stand (20) congestion of moving vehicles and pedestrian 3 In front of NYSC (24) movements. Most of the accidents occurring in 4 Temple Road junction (15) this area is pedestrian involving accidents due 5 Clock tower junction (18) to haphazard crossing of roads. Furthermore 6 In front of urban council (24) vehicle to vehicle accidents occurred at Boe tree junction, Clock tower junction, 7 Bo-tree junction (16) Pamunuwa Road junction and President’s 8 In front of president college (14) College junction with conflicting movements 9 Near telecom (13) due to improper geometric design of above Near Maharagama police junctions. The walkways and carriageways 10 (10) station need to be separated by a pedestrian In front of Buwanekabahu protection fence at each junction, to avoid 11 (09) vidyalaya

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resort to the use of the roads which will WE = WT - WB Here, When total accident weightage was greater increase the pedestrian’s personal safety. WT = 6ft (designed walkway width in year than 15 it was taken as a black spot. Calculated weightages for each location were plotted and 4.17 Traffic island design 2030) is shown in Figure 7. Dehiwala Road junction, Bo-tree junction, Width adjustment factors for walkways, Pamunuwa Road junction and President’s College junction were redesigned using the WB = 2.5 (for light poles) AUSTROADS vehicles and turning path WE = 6 - 2.5 = 3.5ft Total weightage of accidents templates. For this design arterial/collector was used for the intersection road type and v = Vp15/15WE 45 also single unit truck bus was used as the v = 710/15 × (6 - 2.5) = 13.5 ped/min/ft 40 design vehicle. Normally turning speed of 35 townships was 20 km/h. But Pamunuwa and LOS of pedestrian is D [7] Dehiwala are pedestrian congested junctions. 30 For LOS C, Maximum pedestrian flow rate (v) Therefore when designing islands for 25 Total Pamunuwa and Dehiwala junctions 5-15 km/h = 10 ped/min/ft [7] weightag 20 turning speed was selected. Furthermore Bo- e Hence WT = [{710/(15 ×10)} + 2.5]= 7.2 ft 15 tree and President’s College junctions were weightage adopted 0 - 5 km/h turning speed due to Design walkway width =7.2ft (2.19m) 10 geometry of them [8]. 5 Using the same method, Design walkway Figure 6 – Collision diagram 4.18 Analysis of walkway widths widths were calculated for Old Road, High- 0 Data were collected from the pedestrian Level Road, Dehiwala Road and tabulated in 4.16 Identification of black spots Figure 7- Accident1 2 weightage3 4 5for each6 location7 surveys done during the peak hours around Table B.4 in AppendixB. As per accident data from police records it was Location Maharagama area. able to identify eleven high risk accident Analysing the above accident data, the Sample calculation for Old Road: locations; which had more than three accidents 5. Conclusion within four years in study area. Weightages following observations were made. For year 2010; were given to different types of accidents and V =Vp15/15WE 5.1 Improvement of roads in calculated the total weightage of each Five fatal accidents had occurred within Maharagama town area identified black spot locations and ranked WE = Effective walkway width four year period in this study area. High Level Road and Old Road are major them. WT = Existing walkway width roads in Maharagama town area. They will be According to the gravity of accident category directly influenced by additional traffic from Most of the accidents were vehicle to WB = Reduction of walkway width weightages of 5, 3 and 1 were assigned for Kottawa interchange after implementation of Fatal, Grievous and Light respectively [3]. vehicle and vehicle to pedestrian related. WE = WT - WB Here, the Southern Expressway and Outer Circular Highway. In this study Maharagama town Most cases of pedestrians involving WT = 4.3ft P = X + 3 × Y + 5 × Z, where area with main approach roads to the High accidents had happened due to haphazard X = total number of light injuries Width adjustment factors for walkways, crossing of roads. Level Road and Old Road was only Y = total number of grievous injuries considered. Also traffic volume from above WB = 2.5 (for light poles) Z = total number of fatal injuries approach roads which are Dehiwala Road and Pamunuwa Road junction was the major WE = 4.3 - 2.5= 1.8ft Pamunuwa Road was considered for area prone to accidents. Table 2 – High-risk accident locations designing all the roads in this area in year V = 537 / 15× (4.3 - 2.5) = 20 ped/min/ft 2030. According to the collected and observed No. Location Weightage According to the above observations vehicle LOS = E [7] data and analysis carried out, it was observed accidents in Maharagama area was not due to that High Level Road and Old Road are not in 1 Pamunuwa Road junction (39) high speed driving of vehicles but due to By applying the population growth factor of a satisfactory condition to accommodate the 2 Old Road 138 bus stand (20) congestion of moving vehicles and pedestrian 1.4%, the estimated pedestrian flow in year additional traffic from Southern Expressway movements. Most of the accidents occurring in 3 In front of NYSC (24) and Outer Circular Highway once they are in this area is pedestrian involving accidents due 2030 is now calculated as: 4 Temple Road junction (15) operation. Through this study, checks were to haphazard crossing of roads. Furthermore 5 Clock tower junction (18) 537 × (1.01420) = 710 ped / 15 min done to observe the road capacities with vehicle to vehicle accidents occurred at Boe 6 In front of urban council (24) current traffic in year 2010 and additional tree junction, Clock tower junction, Hence in year 2030 7 Bo-tree junction (16) traffic due to Southern Expressway and Outer Pamunuwa Road junction and President’s The average unit width flow rate: Circular Highway in year 2030. According to 8 In front of president college (14) College junction with conflicting movements these checks it was found that present road 9 Near telecom (13) due to improper geometric design of above v =Vp15/15WE capacities will not be sufficient to cater even Near Maharagama police junctions. The walkways and carriageways 10 (10) WE = Effective walkway width the normal traffic growth of traffic on High station need to be separated by a pedestrian Level Road (without any contribution from In front of Buwanekabahu protection fence at each junction, to avoid WT = Walkway width 11 (09) new roads) in year 2030 to function at a vidyalaya WB = Reduction of walkway width satisfactory level of service. Therefore to cater

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to the normal traffic growth and additional introduced at that location to minimize the traffic from two new highways at year 2030, interruption of vehicular flow and to enhance Old Road and High Level Road had to be the safety of pedestrians who used this redesigned as multilane highways by crossing. introducing new lane widths, road widths and by adding reasonable number of lanes to Furthermore black spot locations were maintain a level of service D during the peak identified in study area and according to the flows. Although level of service D is not a weightages they were ranked. According to the satisfactory condition, since it was considered accident analysis most of accidents occurred for peak hours in year 2030 (worst scenario) it when pedestrians were physically crossing the was accepted for this study. roads. Therefore road signs were provided to inform the drivers about the locations of the Both Dehiwala and Pamunuwa Roads are two pedestrian crossings. On the other hand most directional roads in Maharagama town area. of the accidents occurred due to absence of lane But for normal traffic growth by year 2030 they markings. Therefore proper lane markings also will find it difficult to cater to the above were provided for all roads in Maharagama traffic with suitable level of service. Road town area. Furthermore traffic islands were capacities were checked for Dehiwala and designed for main junctions to avoid traffic Pamunuwa Roads and also designed as two conflicts and also improve the pedestrian directional highways by introducing new lane safety. widths, road widths and by adding new lanes to operate at level of service D during peak Acquisition of land and other related activities flows. Designed road widths and lanes were which creates social problems are involved in stated in Table B-3 in Appendix B. the widening of all roads in Maharagama town area. Therefore Old Road and High Level Road 5.2 Walkway shoulders and pedestrian were redesigned with 12ft lane widths with safety five lanes. Pamunuwa Road was designed as a Maharagama town area is a pedestrian multilane highway consisting of 3 lanes for congested area due to commercial buildings each direction with 10ft lane widths. Dehiwala and wayside traders. The current walkway Road was designed as a multilane highway widths were utilized by unauthorized persons with 3 lanes for each direction with 12ft lane such as wayside traders and squatters. widths. Maximum width of zebra crossing was Therefore the walkway widths were reduced designed as 5m and other crossings were and as a result pedestrians tend to use the designed as 3m or 4m considering the relevant carriageway. Hence they lead to an unsafe pedestrians volume. situation. According to the US highway capacity manual all walkway shoulders in Maharagama town area was widened and also References walkway shoulders and carriageways were separated by providing pedestrian safety 1. http://www.rda.gov.lk RDA website, Sri fences at each junction. Designed walkway Lanka. 2011. widths were stated in Table B-4 of Appendix B. 2. Weerasekera, K. S. ‘An Introduction to

Traffic Engineering’ Incolour (Pvt) Ltd., 5.3 Pedestrian crossings and pedestrian Colombo, 2009. safety Zebra crossings were redesigned to improve 3. Wets, G, ‘Black Zones: Black Spot Analysis the level of service of the pedestrians and also Methods’, 2003. all the crossings were checked to identify the current level of service. Road signs were 4. Feasibility Study Report of Southern introduced at each pedestrian crossing to Expressway, Road Development enhance the pedestrian safety. But maximum Authority, 1998. pedestrian volume was observed at the zebra crossing in front of the supermarket, and it 5. Feasibility Study Report of Outer Circular Highway, Road Development Authority, was not enough to provide suitable level of 2000. service for pedestrians. Also this crossing was adversely affecting the vehicular flow on High 6. Mannering, Fred L., Kilareski, Walter P., Level Road causing excessive delays. Washburn, Scott, S., ‘Highway Engineering Therefore pedestrian signalized crossing was

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to the normal traffic growth and additional introduced at that location to minimize the and Traffic Analysis’, 3rd ed. New Delhi: traffic from two new highways at year 2030, interruption of vehicular flow and to enhance Wiley (P) Ltd., 1997. Old Road and High Level Road had to be the safety of pedestrians who used this redesigned as multilane highways by crossing. 7. Transportation Research Board. Highway Capacity Manual. Special Report 209, introducing new lane widths, road widths and Washington, D.C: National Research by adding reasonable number of lanes to Furthermore black spot locations were Council. 1994. maintain a level of service D during the peak identified in study area and according to the flows. Although level of service D is not a weightages they were ranked. According to the 8. Rod George, PUB.RD.N.514. Austroads satisfactory condition, since it was considered accident analysis most of accidents occurred guide and commentary series. Sydney,: for peak hours in year 2030 (worst scenario) it when pedestrians were physically crossing the ARRB Transport Research Ltd., 2005. was accepted for this study. roads. Therefore road signs were provided to inform the drivers about the locations of the 9. Chakroborty, P. ‘Principles of Both Dehiwala and Pamunuwa Roads are two pedestrian crossings. On the other hand most Transportation Engineering’. 1st ed. New Delhi: Prentice-Hall of India Private directional roads in Maharagama town area. of the accidents occurred due to absence of lane Limited., 2003. But for normal traffic growth by year 2030 they markings. Therefore proper lane markings also will find it difficult to cater to the above were provided for all roads in Maharagama 10. Weerasekera, K. S. ‘Bridging the Gap traffic with suitable level of service. Road town area. Furthermore traffic islands were towards Safer Roads – What is in capacities were checked for Dehiwala and designed for main junctions to avoid traffic between?’, Proceedings of the UN-ESCAP Workshop on Developing Road Safety Pamunuwa Roads and also designed as two conflicts and also improve the pedestrian directional highways by introducing new lane safety. Strategy & Goals, Ministry of Highways widths, road widths and by adding new lanes and Road Development, Government of rd to operate at level of service D during peak Acquisition of land and other related activities Sri Lanka, 3 December 2009. flows. Designed road widths and lanes were which creates social problems are involved in stated in Table B-3 in Appendix B. the widening of all roads in Maharagama town area. Therefore Old Road and High Level Road 5.2 Walkway shoulders and pedestrian were redesigned with 12ft lane widths with safety five lanes. Pamunuwa Road was designed as a Maharagama town area is a pedestrian multilane highway consisting of 3 lanes for congested area due to commercial buildings each direction with 10ft lane widths. Dehiwala and wayside traders. The current walkway Road was designed as a multilane highway widths were utilized by unauthorized persons with 3 lanes for each direction with 12ft lane such as wayside traders and squatters. widths. Maximum width of zebra crossing was

Therefore the walkway widths were reduced designed as 5m and other crossings were and as a result pedestrians tend to use the designed as 3m or 4m considering the relevant carriageway. Hence they lead to an unsafe pedestrians volume. situation. According to the US highway capacity manual all walkway shoulders in Maharagama town area was widened and also References walkway shoulders and carriageways were separated by providing pedestrian safety 1. http://www.rda.gov.lk RDA website, Sri fences at each junction. Designed walkway Lanka. 2011. widths were stated in Table B-4 of Appendix B. 2. Weerasekera, K. S. ‘An Introduction to

Traffic Engineering’ Incolour (Pvt) Ltd., 5.3 Pedestrian crossings and pedestrian Colombo, 2009. safety

Zebra crossings were redesigned to improve 3. Wets, G, ‘Black Zones: Black Spot Analysis the level of service of the pedestrians and also Methods’, 2003. all the crossings were checked to identify the current level of service. Road signs were 4. Feasibility Study Report of Southern introduced at each pedestrian crossing to Expressway, Road Development enhance the pedestrian safety. But maximum Authority, 1998. pedestrian volume was observed at the zebra crossing in front of the supermarket, and it 5. Feasibility Study Report of Outer Circular Highway, Road Development Authority, was not enough to provide suitable level of 2000. service for pedestrians. Also this crossing was adversely affecting the vehicular flow on High 6. Mannering, Fred L., Kilareski, Walter P., Level Road causing excessive delays. Washburn, Scott, S., ‘Highway Engineering Therefore pedestrian signalized crossing was

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APPENDIX - A Proposed Design Layouts

Figure A.1 - Island design for Boe tree Figure A.4 - Island design for Pamunuwa junction Road junction

Figure A.2 - Island design for President’s Figure A.5 - Final design for President’s College junction College junction

Figure A.6 - Final design for Dehiwala Road Figure A.3 - Island design for Dehiwala Road junction junction

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APPENDIX - A Proposed Design Layouts APPENDIX - B

Table B.1 - Total number of vehicles within

12 hour time period

Time Total no of vehicles

Two Maharagama Colombo to Table B.2- Pedestrian volume data at directional Clock tower junction to Colombo Maharagama Total volume

7.00-8.00 1776 730 2506

7.30-8.30 1844 730 2574 5 min At Morning At Evening interval peak peak Figure A.1 - Island design for Boe tree 8.00-9.00 1625 672 2297 Figure A.4 - Island design for Pamunuwa V out Vin V out Vin junction Road junction 9.00-10.00 1177 720 1897 1 32 78 103 76 10.00-11.00 1019 850 1869 2 31 82 127 80 11.00-12.00 1052 819 1871 3 52 68 165 116 12.00-13.00 956 862 1818 4 24 69 98 67 13.00-14.00 763 872 1635 14.00-15.00 812 993 1805 5 31 44 143 89 15.00-16.00 778 888 1666 6 45 46 102 34

16.00-17.00 807 768 1575 7 36 58 87 90

17.00-18.00 733 1197 1930 8 26 54 120 57

17.30-18.30 733 1323 2056 9 23 30 85 22

18.00-19.00 662 1323 1985 10 39 37 198 83 Figure A.2 - Island design for President’s Figure A.5 - Final design for President’s Total 12 11 45 55 129 60 College junction College junction 14737 12747 27484 hour 12 39 39 95 14

Table B.3 - Results of designed Road Widths and Lanes

Width of Shoulder SF MSF No of i the lane width f f f f Location (pcuph) lanes w hv e p ft ft (pcuph) (m) (m) 12 6 High level Road 1600 5 0.727 0.900 0.8 1 4187 (3.658) (1.829) 12 6 Old Road 1600 5 0.872 0.898 0.8 1 5013 (3.658) (1.829) From 12 6 Maharagama 1600 3 0.928 0.907 0.8 1 2587 (3.658) (1.829) Dehiwala to Dehiwala Road From 12 6 Dehiwala to 1600 3 1.020 0.943 0.8 1 2956 Figure A.6 - Final design for Dehiwala Road (3.658) (1.829) Maharagama Figure A.3 - Island design for Dehiwala Road junction From 10 5 junction 1600 3 0.726 0.972 0.8 1 3305 Pamunuwa Pamunuwa (3.048) (1.524)

Road 10 5 To Pamunuwa 1600 3 1.100 1.000 0.8 1 4130 (3.048) (1.524)

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Table B.4- Pedestrian LOS for walkways

In 2010 In 2030 Designed widths Vp15 V Vp15 V Location WE WE WT LOS Ped/ ped/min LOS Ped/ Ped/ LOS ft ft Ft(m) 15min /ft 15min min/ft

Old Road 7.2 537 1.8 20 E 710 3.5 13.5 D C (2.19) High- 7.4 Level 560 2.9 13 D 740 3.5 14.1 D C (2.26) Road Dehiwala 7.52 570 4.6 9 C 753 3.5 14 D C Road (2.29)

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