Penang’s draft plan could open more of its hills to building

Kam Suan Pheng and Evelyn Teh

“Rising from the sea in that first light of dawn that touches reality with a gentle charm, the Penang hills provide an unforgettable landmark for the visitor sailing in by sea. From the palm-fringed bays as yet a black indistinguishable smudge, the eye follows the flowing silhouette of the hills.” – Margaret Khor, The Straits Times Annual, 1960.

Ask anyone who has crossed on the ferry, or driven over the bridge at dusk, and they will say the same: that green line of hills is how you know you are home. That silhouette is part of what makes Penang, Penang.

Beyond the scenery, the hills are part of the island’s natural public infrastructure – one that is rarely counted. They hold soil, absorb and direct water, support forests and wildlife, and shape the landscape where we and our ancestors have lived.

That landscape could change significantly if the draft state structure plan for 2040 is adopted without stronger safeguards for hill and slope development.

First, some background. The current Penang State Structure Plan 2030 does not allow development on land 76 metres (250 feet) or more above sea level, or on slopes of 25 degrees or steeper. There are limited exceptions for infrastructure and utilities.

The limit is stricter than the national guideline. The state set it because it recognised how fragile, and how important, the island’s hills are.

The 2030 plan reads:

Sebarang Pembangunan Perbandaran Yang Meliputi Pembangunan Skim Perumahan Perhotelan Resort Perdagangan Perindustrian Dan Sebarang Struktur Bangunan Footprint Tidak Dibenarkan Di Kawasan:-

• • Kawasan Tanah Tinggi Yang Diwartakan Di Bawah Akta Pemeliharaan Tanah 1960 Akta 385 Atau
  • Sebarang Tanah Yang Berada Pada Aras 76 meter 250 kaki) Ke Atas Atau
  • Kawasan Berkecerunan 25 Darjah Ke Atas

KECUALI Bagi Pemajuan Infrastruktur Dan Utiliti Dibenarkan Dengan Syarat Syarat Dari Jabatan Teknikal Yang Berkaitan Dan Mendapat Kelulusan Dari Pihak Berkuasa Negeri.

In English:

Any urban development, including housing schemes, hotels, resorts, commercial or industrial developments, and any building structures, is prohibited in the following areas:

• • Highland areas gazetted under the Land Conservation Act 1960 (Act 385); or
  • Any land situated at an elevation of 76 metres (250 feet) or higher; or
  • Areas with a slope gradient of 25 degrees or steeper;

EXCEPT for infrastructure and utility developments, which are permitted subject to conditions imposed by relevant technical departments and approval from the State Authority.

The key concern

The state government rolled out a new draft Penang State Structure Plan 2040 in August – years before 2030 arrives. It will override the 2030 structure plan.

The draft 2040 plan says:

Strategi Perancangan PS3-1: Pembangunan di Kawasan Khusus yang Melebihi Ketinggian 76 meter. Strategi ini merupakan pendekatan perancangan yang memberi kelonggaran kawalan ketinggian bangunan secara terpilih di kawasan khas yang telah dikenal pasti sebagai kawasan tumpuan pembangunan strategik. Pelaksanaan strategi ini bertujuan mengoptimumkan penggunaan tanah yang terhad melalui pembangunan berintensiti tinggi dan berorientasikan transit, khususnya di pusat bandar, koridor ekonomi dan kawasan pesisir yang mempunyai kapasiti infrastruktur mencukupi. Walau bagaimanapun, kebenaran ini tertakluk kepada penilaian teknikal terperinci seperti kesesuaian guna tanah, nisbah plot, kawalan kepadatan, impak trafik, keselamatan, impak visual serta pematuhan kepada garis panduan reka bentuk bandar dan kajian impak alam sekitar.

In English:

Planning Strategy PS3-1: Development in Special Areas Exceeding a Height of 76 Metres. This strategy is a planning approach that allows for selective flexibility regarding building height controls in specific areas identified as strategic development hubs. Its implementation aims to optimize limited land use through high-intensity, transit-oriented development, particularly in city centres, economic corridors and coastal areas with adequate infrastructure capacity. However, such approval is subject to detailed technical assessments covering aspects such as land-use suitability, plot ratio, density controls, traffic impact, safety, visual impact, and compliance with urban design guidelines and environmental impact studies.

In plain terms, the 2040 draft swaps ‘don’t build there’ (in the 2030 plan) for ‘build there if the paperwork says it’s safe’.

The 2030 plan took a precautionary approach: keep away from the risk altogether.

The 2040 draft replaces it with case-by-case approval, where each project’s own technical studies decide whether a hill can take it.

Are these adequate safeguards, or is this a problem waiting to happen?

Why change the limit?

The threshold of 76m above sea level was not arbitrary. It was a deliberate safeguard that Penang chose to keep.

Penang had adopted stricter controls than the national KSAS (environmentally sensitive areas) elevation framework, which it is now reverting to.

The Safety Guideline for Hillsite Development (second edition, 2020) says Penang Island covers roughly 285 sq km. About 40% of it is Class 3 and Class 4 land, with slopes steeper than 25 degrees.

The first version of the guideline went further. It reduced the footprint of buildings on hill land to make slopes safer and keep more green areas.

Now these precautions are set aside. The 2040 draft presents this as a development strategy, not as a finding that the 76m limit is irrelevant.

Outside the draft, no new evidence, assessment or policy review shows that the precautionary approach is no longer needed.

What evidence, then, supports such a significant change in risk management?

Look closely at the numbers. The highest point in Penang is 833m above sea level, but the horizontal area of the hills is small. The slopes are therefore compressed into a limited range of height and width.

Add the complex pattern of hills and ridges, and very few pockets of land are flat enough to build on without cutting into the surrounding slopes.

Even if building is allowed on isolated pockets, the roads needed to reach them must cross steeper terrain. Their environmental impact will reach far beyond the site.

We do not have to imagine what that looks like. In October 2017, a landslide at a construction site in Tanjung Bungah killed 11 workers. A year later, part of a ‘paired road’ at Bukit Kukus collapsed during construction, killing nine.

Bukit Kukus was a road, exactly the kind of infrastructure the 2030 plan already allowed as an exception. If the exception alone could cost so many lives, what happens when the rule itself is lifted?

This is probably why past planners chose the 76m (250ft) limit. That wisdom applies even more today, as climate change brings heavier and more frequent rain to fragile hills.

And what happens on the hill does not stay on the hill. These slopes feed the Air Itam and Teluk Bahang dams that fill our taps. When forests can no longer hold the rain, it runs down into lowland streets as flash floods.

One does not need to live on a hill to pay for what happens on one.

Paperwork is not landscape planning

Some may argue that a technical assessment before approval is a reasonable safeguard.

It can tell us whether a project meets existing standards. These include the Penang Safety Guideline for Hill Site Development 2020, the EIA Guidelines for Development in Slope and Hill Areas issued by the Department of Environment, and the planning and management guide for environmentally sensitive areas by PLANMalaysia.

But none of these answers the bigger question: how many projects can these hills absorb before the whole system gives way?

The 2040 draft says hill development control is strengthened through risk assessment, including the environment’s carrying capacity and climate resilience. Any development on hill land between 300 and 1,200 metres, or between 150 and 300 metres, and on slopes above 25 degrees, must submit a geotechnical risk assessment and a climate risk assessment.

However, we know of no publicly accessible study or official database that gathers the information needed as a baseline. This should be established before the first hill or slope proposal is submitted.

It seems the draft simply adopted a guideline written for the highlands of the peninsula – not one drawn up for Penang island.

Could we, or should we?

With today’s engineering, there are many ways to stabilise a slope: retaining walls, modern drainage, soil nails, piles and engineered slopes. A project may well be shown to be safe on paper.

But the natural slope will have been substantially altered. Its long-term safety then rests on things no approval can guarantee. These include construction quality, drainage maintenance, inspection, the capacity and funding of the agencies responsible, extreme weather and future changes in land use.

The irony is that a retaining wall is only as safe as the last time someone cleared its drains.

There is also no baseline of existing conditions or of the role the hills play. That role covers the watershed, ecological corridors, natural drainage and geological formations.

Penang lacks a hill and slope master plan that understands how sensitive and connected the hills are. Only such a plan can properly define, map and measure the hills’ carrying capacity, including projected climate scenarios.

So the question shifts. We could make hill and slope development safe. But should we, and at what cost, when we have no baseline data and no guarantee these projects will stay safe in the long term?

A project being technically safe is not the same as the landscape being safe.

Gazette first, assess later

When a gazetted state structure plan marks an area as potentially developable, the effects ripple out quickly. Land values rise, investors form expectations, land changes hands, proposals are drawn up and contracts are signed.

All of this happens long before any environmental impact or technical assessment is complete.

That order of events tilts the outcome.

Once money and contracts are committed, rejecting a project on environmental grounds carries legal and financial consequences. The seemingly rational way out is to reduce every risk to an ‘acceptable’ level and hope nothing goes wrong later. The assessment no longer decides whether to build, only how.

Show us the evidence

The 2040 draft marks a significant shift from precautionary restriction towards risk-based conditional development. That may be reasonable in some circumstances.

But the draft must show why the previous limits are no longer needed. It must also explain how project-by-project checks will deal with risks that build up across the landscape, worsen with climate change and cannot be undone once a hill is cut.

If Penang is deliberately moving beyond the precautionary framework to create more development opportunities, it should show us the evidence. That means the thresholds and landscape-level safeguards that justify the change, in the form of a hill and slope development master plan, published before the 2040 plan is gazetted, not after.

In the end, for most of us, this is not really a debate about slope angles, geotechnical reports or even the state structure plan.

It is about the hills we know, some of us since childhood. These are the hills we see from our windows, or on the drive home after a long day at work. On them lie the green trails we climb at weekends to take in the view of our beloved Penang from above.

It is also about feeling safe when the torrential rain comes. Can we sleep soundly knowing the hills near us will keep doing what they have always done: holding the soil, soaking up the water and slowing the runoff before it reaches our neighbourhoods?

Or will we rely more and more on concrete walls and drains to protect us from hills we ourselves have altered?

Note: The public display of the draft 2040 Penang Structure Plan ends on 9 October 2026, which is also the extended deadline for public feedback, which you can submit using this online form.

Dr Kam Suan Pheng is a soil scientist and co-founder of Penang Hills Watch, with a doctorate in agronomy-soil from Cornell University. Evelyn Teh is a Penang-based public policy researcher and environmental scientist specialising in ecological management, climate change and urban studies.

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