Sector Road

Project Type Expressway Construction

Project Title Outer Circular Highway to the City of Colombo Project

Location Colombo District and Gampaha District, Western Province, Sri Lanka

Client JICA / Road Development Authority, Ministry of Highways, Ports and Shipping

Project Period November 1998 – Present

Problems addressed by the Project

Before 1990’s, the transport sector development policy of the Government of Sri Lanka (GOSL) had been to basically rehabilitate its existing road and rail infrastructure. That was only rehabilitation work and was undertaken to improve the transportation system, via the execution of a number of road rehabilitation and improvement projects. However, traffic demand increased very rapidly in the past decade and there was a shortage of road capacity to satisfy this rising demand. Hence, the GOSL decided to develop a system of new highways (expressways) to supplement existing road capacity. Under the above policy, Outer Circular Highway to the City of Colombo (OCH) was planned as the one of expressways aiming to relieve traffic congestion in the Colombo Metropolitan Region (CMR).

OCH was initially considered in a 1991 proposal of the Road Development Authority, which resulted in a pre-feasibility study being carried out and completed in 1993. After that, according to the request from the GOSL, JICA funded the Project and Feasibility Study (FS), Basic and Detailed Design Studies were carried out.

In the FS, it was proposed that the Government would construct a 51.26 km circular highway, which would consist of four sections and connect seven high-priority trunk roads radiating from Colombo as well as a number of planned intercity expressways. Subsequently, however, the scope of the JICA funded Project was reduced from Kottawa Interchange, which provides access to A4 road and connecting point with Southern Expressway, to Kadawatha Interchange, which provides access to A1 Road.

Service Provided

OC Global conducted JICA funded FS from 1998 to 2000 and JICA funded Basic and Detailed Design Studies from 2001 to 2008, including suspended periods. We were subsequently engaged and provided the design review, tender assistance and the construction supervision services from March 2008 through to 2015.

Actual Project Works

1. Southern Section (Phase I): Kaduwela-Kottawa: L= 11 km, 4 lanes (6 lanes in the future) carriageway, Design Speed: 100 km/h (partly 80 km/h) 3 interchanges with toll plaza, 5 long-scale bridges with a total length of 3.9 km and 7 small to medium

bridges, 20 box culverts Soft ground treatment of 8.7 km with gravel mat, band drain, geotextile, surcharge and gravel replacement

methods

2. Northern Section 1 (Phase II): Kadawatha-Kaduwela: L= 8.9 km, 4 lanes (6 lanes in the future) carriageway, Design Speed: 100 km/h and L=1.9 km, 4 lanes A1

Bypass 2- interchanges with toll plaza, 16 long-scale bridges (total length 6.5 km) with 4.7 km main carriageway

bridges including a bridge across the Kelani River (appox. 380 m) and 5 small to medium bridges, 39 box culverts,

Soft ground treatment of 5.4 km with the said treatment methods and additional gravel compaction pile method