DEVELOPMENT projects on hill slopes always draw the ire of residents living in the surrounding area. With the numerous stories of landslides and the lack of access to a developer’s development plans, it is understandable that the public has little tolerance for such development projects. In far too many cases, hill slope development has resulted in the tragic loss of lives and damage to property.
But whether residents can present a good enough argument against a hill slope development depends on the information they have at their disposal.
For this reason, I am happy to recommend the book titled Slopes Made Simple by Sheikh Abdul Wahed Datuk Rahim.
Introduction and format
To the layperson, one landslide may seem no different from another since the result is a pile of rubble at the bottom of the slope. The book explains the different causes of landslides and the related technical terms in an easy-to-follow manner.
Technical issues involving slopes are introduced with simple graphics and step-by-step explanations. Each technical issue is broken down into its own chapter and is easily comprehensible.
The book also provides many examples of cause and effect resulting from good and bad practices involving slope design, construction and maintenance. Newspaper clippings and photos of actual slope construction and slope failures are used to great effect here.
Aside from the technical details of slopes, there are also chapters dedicated to all the various design factors that keep a slope from collapsing. These include drainage and retaining walls, and how they work or fail to work due to bad planning and design.
An entire chapter is dedicated to water as it is usually the main cause of soil erosion and landslide. With heavy Malaysian rainfall almost all year round, erosion and the added weight of water on a porous land embankment are some of the factors that must be considered and dealt with seriously.
Landslide at Hutan Pendidkan Bukit Gasing, April 2008 (Source: savebukitgasing.wordpress.com)
Tips on problem recognition and slope maintenance are provided, along with a pictorial guide on the telltale signs to look out for in the surrounding infrastructure. For example, the type of cracks in buildings, walls and roads that forewarn an impending landslide.
One particular chapter that I would like to excerpt concerns plastic sheets that we so often see around eroded hill slopes. The author warns that this exercise actually aggravates the erosion when sheets cover only part of the eroded surface. This is because water will not be absorbed into the ground. Instead, it will run off freely on the sheets and gather momentum as it hits the bottom, hence causing more widespread erosion.
Additionally, the book highlights the danger of not maintaining the support infrastructure around a hill slope development. Even if the support infrastructure is expertly designed and built, if it’s not well maintained, it could become a catalyst in the future for a landslide.
It also bears remembering that the maintenance of a housing estate’s infrastructure falls under the local council. Unfortunately, there is no proper inventory system to ensure that maintenance is carried out consistently. Hence, the public has every reason to be concerned about a hill slope development’s safety many years after a developer has finished the job and moved on.
The fact that local authorities aren’t liable for any loss of life or property damages because of a clause in the Streets, Drainage and Building Act doesn’t help the situation, either.
Reading through the book has helped me appreciate the public insecurity and doubt over hill slope development projects. The numerous pictured examples of bad design and bad practices that result in landslides are staggering. Many of these examples involve federal government road projects. Indeed, if the authorities can be sloppy and do things wrongly, how can the public accept their safety assurances?
Damage caused by the Bukit Antarabangsa landslide on 6 Dec 2008 (Pic by Raj Kumar)
This is not to say that I am totally against hill slope development. Personally, I would propose a two-phase development for hill slope projects. The first phase would involve building the entire support infrastructure of drains and retaining walls.
Should the first phase be completed to the satisfaction of the public (residents should be provided funds by the local council to hire their own technical expert), the developer may then proceed with the next phase of development. The local council should also come up with a permanent maintenance schedule that can be double-checked by residents living in an area so their fears can be allayed.
Alas, my suggestions would probably increase the development cost many-fold, and property developers will no doubt protest.
MBPJ councillor KW Mak was not paid to promote Slopes Made Simple. Instead, he views this article as a public service announcement for residents who are keen to learn more about what causes landslides and take steps to prevent them. The book is available at most major bookstores and online.
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