Global Trends by Martin Khor

Monday 6 November 2017

Hills, landslides, floods:  What to do?

Tragic landslide in Penang, flash floods in Kuala Lumpur and Petaling Jaya, and shrinking water catchment area in Ulu Muda … it’s time our leaders tackle the root causes and pay serious attention to the environment.


The news has been full of the related issues of hill cutting, logging, landslides and floods.  The environmental crisis is back in the public consciousness, and we should seize the moment to find solutions and act on them.

Penang has been the epicentre of this upsurge, for good reasons:  the 15 September mega flash floods and landslides, and the 21 October hill slope collapse at Lembah Permai (Tanjung Bungah) which killed 11 employees at a construction site.

But it’s not just a Penang phenomenon.  On 30 October, flash floods caused massive traffic jams in Kuala Lumpur and Petaling Jaya.  

Federal Territories Minister Datuk Seri Tengku Adnan Tengku Mansor said the floods were caused not only by heavy rain but by developers of two projects that had blocked drainage.  


A stop work order would be issued if the developers do not take measures specified by City Hall.

Another threat is the logging of valuable water catchment areas.  The Ulu Muda forest in Kedah, which provides much of the water supply to Kedah, Penang and Perlis, is under such a threat as the originally designated Ulu Muda water catchment area has shrunk by 87 per cent from 98,400ha in 1969 to 12,484ha in 2017.    


The forest reserve was the most important water catchment area in the Northern Corridor Economic Region but timber production there was growing because Kedah depended on logging as a source of income, said Penang Water Supply Corporation CEO Datuk Jaseni Maidinsa (The Star, 27 October).

He suggested that the federal government compensate Kedah for gazetting and preserving Ulu Muda as a water catchment area, otherwise the water supply to 4.09 million consumers in Kedah, Penang and Perlis as well as their economies will be threatened by logging.

Jaseni issued this stark warning:   When logging affects the Muda Dam’s ability to store sufficient water, “three states will face a catastrophic water crisis in the next dry season.”

In Penang, the debate on the floods and the tragic landslide has continued non-stop and moved last week to the State Assembly.

The clearest explanation of the worsening flood situation that I have was the presentation by scientist Dr Kam Suan Pheng at the Penang Forum event on 29 October.

A former USM academic who then worked in international agencies including the International Rice Research Institute, Dr Kam said there were seven main causes of floods in Penang:

·         Increasingly heavy rainfall;

·         Expansion of impermeable surface area;

·         Eroded soil and landslides increase the sediment load in surface runoffs;

·         Debris that clog up waterways;

·         Accumulation of surface flow downstream;

·         Limited capacity to channel off discharge; and

·         High tides slow down discharge to the sea.

She provided historical and current data to show that flash floods are happening more frequently and with more adverse effects, even with lower rainfall levels.   With higher rainfall expected in future, the situation can be expected to significantly worsen.

Dr Kam focused on expansion of impermeable surface area (caused by ill-planned development and replacing natural ground cover such as hills, fields and trees that act as a water-absorbing sponge) and soil erosion and landslides (caused by cutting and development in hill areas) as two factors that need special attention.

She quoted Datuk Ir Kam U Tee, the Penang Water Authority General Manager 1973-90) as having correctly explained the Penang floods of 15 October 2008 as follows:  “The floods were caused by conversion of the Paya Terubong and Bayan Baru valleys into concrete aprons that do not retain water.  The water immediately flows into streams causing flash floods even with moderate rainfall.  Because of hill-cutting activities, the flowing water causes erosion of the slopes which carries mud and silt into the river beds.” (as reported in The Star, 24 October 2008).

Flood mitigation and flood prevention are two types of actions to tackle the flood problem, said Dr Kam.  Mitigation measures only tackle the symptoms, are costly and need public (state and federal) funds.  These include structural measures (upgrading rivers, installing pumps) and non-structural measures (drainage masterplan; flood forecasting and warning systems; public education).

Flood prevention should be the priority as they tackle the root causes, said Dr Kam, who proposed the following actions:  

·         Proper land use planning and development control;

·         Environmental, drainage, transportation and social impact assessments should be made regarding development plans, beyond individual development projects;

·         Stringent protection of hill land and slopes;

·         Stringent monitoring of development projects;

·         More greening of urban spaces, including a system of parks; and

·         Protection of river banks.

To take these measures, policy makers have to deploy a wide range of policy and legal instruments, and to adopt environmentally-sensitive and ecologically-friendly structural and non-structural solutions, concluded Dr Kam.

Another speaker, Dato’ Agatha Foo, complemented Dr Kam nicely when she elaborated on the various laws, guidelines and plans that can be used to prevent the wrong kinds of development, to control and monitor approved developments and to strictly enforce the laws. 

She also spoke on the loopholes and weaknesses of the laws and how to correct them.

Events of the past few weeks alone indicate that the number of environment-related and human-made problems are bound to increase, probably many times, unless our leaders and policy makers give higher priority to the environment and to well-planned development.  

The paradigm shift should start now, as the alarm bells have already rung.