Cilmatic Risk Assessment Of Southern Express Way in Sri Lanka

Climatic Risk Assessment on

Southern Expressway in Sri Lanka

Climatic Risk Assessment on

Southern Expressway in Sri Lanka

BY

S.D. Kelum Priyantha

Thiwanka Jayasiri

MSc in Geoinformatics

IHRA

University of Colombo

28th June 2014

• The Southern Expressway,

also known as the Southern

Lanka Distributor is Sri

Lanka's first E Class highway.

• The 126 km long highway

links the Sri Lankan capital

Colombo with Galle and

Matara, major cities in the

south of the island

• Rainfall

• Temperature

• Bends

• Flood

• Landslides

Average Rainfall (mm)

• Dry zone → < 1,750

• Intermediate zone → 1,750-2,500

• Wet zone → > 2,500

Located in

Wet Zone

Geometric Design of road

Vs

Weather

Deflection Angle

There are lot of bends

associated with

southern expressway

Bend Index are

calculated as follows

(Deflection angle/Bend

length) * 100

If Bend Index is high then risk

also high

Rain Fall

First Inter MonsoonMarch-April

Southwest MonsoonMay – September

Second Inter monsoon October-November

Northeast MonsoonDecember-February

Rainfall Trend (mm/year)

Temperature

Temperature January, February

July - December

Temperature March

Temperature April

Temperature May

Temperature June

Landslide

Landslides (1947 - 1996)

Landslides Risk DS Divisions

Flood

Flood Risk At 1m elevation










Risk Analysis Chart for Rainfall

( Risk Barometer )

Risk Analysis Chart of Rain Fall

(km)

First Inter monsoon Southwest Monsoon Second Inter monsoon Northeast Monsoon

• Premature deterioration of infrastructure

• Damage to roads from buckling and rutting

• Damage to tires of vehicles

• Bridges subject to extra stresses through thermal expansion

and increased movement

Climate Change Impacts on the Highway

System

Change in extreme maximum temperature

• If more rainfall, there will be an increased risk of landslides, slope failures, and floods from the runoff, causing road washouts.

• Increasing precipitation could lead to soil moisture levels becoming too high (structural integrity of roads, bridges, and tunnels could be compromised leading to accelerated deterioration)

• Less rain available to dilute surface salt may cause steel reinforcing in concrete structures to corrode

• Road embankments at risk of subsidence

• Bridges, signs, overhead cables, tall structures at risk from increased wind speeds

Climate Change Impacts on the Highway

System

Greater changes in rainfall levels

• Weather phenomenon such as rainfall,

temperature, wind, fog and disaster such as

flood, landslides and extreme weather events

that could in some way affect the operations

of a transportation system or facility.

Findings

Findings

• The highway is mainly in the wet zone.

• The drivers faces two main problems due to

climatic conditions. Rain and Fog.

• In addition strong winds may cause specially

on rainy days.

• No street lamps along the road except in main

junctions.

Safety Process

Safety Precautions

• Identifying the most risky areas along the road and risky seasons using Risk Analysis Charts ( Risk Barometer )is very important.

• Identify the risky places where should establish sign boards and use ‘Dynamic electronic speed limits sign boards’ according to weather conditions. Specially in rainy days drive “below” the speed limits.

• Encourage drivers to use fog lights when driving in the fog.

• Use head lights even in day time when driving in rain or fog.

• Make sure of the lights and wipers are in proper order before entering to the highway.

• Make aware the drivers regarding weather conditions by mentioning on the ticket of the day before entering to the highway.

• Properly check whether vehicle & driver are in allowed conditions.

• In case of flood, find the solution to make connection between expressway and general road network

• Make precautions by analyzing of weather trends such as rainfall, Temperature due to global warming, tsunami, Landslides

Travel

Cilmatic Risk Assessment Of Southern Express Way in Sri Lanka