Penang’s shores in peril: a deadly mix of climate change and coastal development”

GEORGE TOWN – Is the coastal erosion in Penang purely a naturally occurring phenomenon, or was it triggered by human activities?

According to experts and a government agency, it is both, as the dreaded combination of climate change-induced extreme weather patterns and coastal developments that have accelerated the coastal erosion on beaches in Penang, which is already sparking concerns among Penangites.

Marine ecologist, Associate Professor Mahadi Mohammad of Universiti Sains Malaysia (USM) said that the coastal erosion problem in Penang has become a pressing environmental concern, which is affecting both the island and mainland, although the problem varies in intensity across different locations.

On Penang island, Mahadi said that the northern coastal areas such as Batu Ferringhi, Tg Bungah, and Teluk Bahang face significant erosion. These zones, known for their dense tourism-related infrastructure, are particularly vulnerable due to their development and exposure to wave action, he said. Meanwhile, on the mainland, erosion hotspots were identified in coastal stretches in Butterworth and Nibong Tebal, where low-lying areas are particularly at risk.

“Current data from the Department of Irrigation and Drainage (DID) and academic studies reveal an average erosion rate of 0.5 to 1 m annually in critical locations. However, the rate may be substantially higher during extreme weather events, including monsoons and storms,” said Mahadi in an email to Scoop.

Geographical, climate-induced factors

Mahadi also said that the rise in sea level, which is accelerated by climate change, has increased wave energy, thus inundating low-lying areas in Penang and intensifying the coastal erosion problems.

The academic noted that the strong waves and storm surges, particularly during the northeast and southwest monsoon seasons, have eroded coastal lands and exacerbated sediment displacement.

Echoing Mahadi’s views is the Penang DID, which told Scoop that the concurrence of big tides, strong winds and heavy downpours would cause overflow of seawater, coastal flooding, as well as damage to beach banks in certain parts of the state.

Geographic locations of the coastal areas also play a role in the erosion problem, with the Penang chapter of the Malaysian Nature Society (MNS Penang) saying that the position of the coastal areas is making them susceptible to multiple impacts of climate changes, especially sea level rise.

“Sea level rise could lead to changes in current speed, height and direction (of waves) which is translated to more eroding potential. Coupled with other climate forces such as frequent rainfall, increased storm frequency and intensity, coastal erosion will become an inevitable issue,” the green group told Scoop, adding that the erosion would be worse at the low-lying areas such as the river mouth and delta.

Human activities

All three parties are also unanimous in attributing Penang’s coastal erosion problem to human activities, as they point towards land reclamations, mangrove deforestation and coastal urbanisation that involves the development of structures which include resorts, hotels and seawalls.

Mahadi said that the construction of buildings along the coastal area, which is being done without sufficient environmental assessments, disrupts sediment flow and weakens natural coastal defences against erosion. He also cited both legal and illegal sand mining operations as a contributing factor, as they deplete sand reserves, thus accelerating shorelines’ vulnerability to erosion.

Additionally, DID cited pollution as a contributing factor as both sea and trash pollution could damage beach ecosystems by ruining the vegetation that grows on the beach, hence accelerating the erosion process.

Mahadi is concerned that the coastal erosion, which is not limited to Penang, would lead to loss of coastal habitat that would impact fauna species such as turtles, shorebirds and fish. Additionally, coral reefs and seagrass beds, which are critical for biodiversity and coastal protection, also suffer from sedimentation caused by erosion, he said.

“(Plus) erosion threatens tourism-dependent infrastructure, including hotels and beaches, resulting in financial losses. Fishing communities are facing reduced catch volumes due to habitat degradation, (which is) undermining (their) livelihoods.

“Receding shorelines (also) cause displacement and the loss of ancestral land in coastal communities, (impacting) mainly rural communities,” he added.

Mitigation measures

Mitigating the impacts of coastal erosion in Penang comprehensively would require a combination of proactive measures adopted by both the state and federal governments, with both Mahadi and MNS Penang suggesting the authorities adopt sustainable engineering solutions such as installing breakwaters, artificial reefs, and groynes to mitigate wave impacts while preserving natural processes.

“Hard structures such as revetment and seawall should be used as the last resort as they lack wave energy absorption properties,” added MNS Penang.

Both parties also recommended that the authorities protect existing mangrove forests and reforest degraded mangrove areas as well as other coastal vegetation as they are natural wave breakers.

They also encouraged the authorities to strengthen monitoring and enforcement against sand mining from beaches and nearby seabeds in all forms, as well as unregulated coastal development.

“(Authorities should also) impose stringent controls on any future development proposal near the coast such as jetty, port, building and land reclamation which would alter the natural flow of sediment, sand and current along the shores,” added Penang MNS.

Additionally, MNS’ president Anna Wong – who also spoke to Scoop – took a one-step further by suggesting that there should be no new development of condominiums, malls and infrastructure along the coastal area to reduce coastal erosion.

“(Also) there should be a buffer zone along the coastline which means no any activity to be carried out there. The width of the buffer zone (could) vary, from 30m to 100m from the coastline,” said Wong, who was a former senior lecturer at Universiti Malaysia Sabah’s (UMS) Institute for Tropical Biology and Conservation (ITBC) and Faculty of Tropical Forestry.

Ongoing actions by DID

Meanwhile, Penang DID shared that it has imposed conditions that new developments along the seashores and rivers comply with various guidelines and timely instructions issued by the national DID.

It also said that it is currently conducting a review of Penang’s Integrated Shoreline Management Plan (ISMP), which is expected to be completed in March next year. The ISMP will study the status of coastal erosion based on the categories fixed by the 2015 edition of the National Coastal Erosion Study (NCES) report.

The management plan, according to the department, would also evaluate selected erosion mitigation measures that were recommended in the 2015 report and select beach development management strategies along coastlines, among others.

Penang DID also said that it is currently implementing three beach bank construction and repair projects in the mainland: Bagan Ajam beachfront in Butterworth (expected completion in March 2026), Mak Minah beach in Juru (expected completion in August 2025), and Byram beach in Nibong Tebal (expected completion in September 2025).

As for the island, the department has applied for allocations under the 5th Rolling Plan of the 12th Malaysia Plan for the “Outfall Construction and Coastal Erosion Prevention Structure Project” in Tg Bungah and Batu Feringghi.

“The project’s objective is to control coastal erosion using suitable methods, which would allow river water to flow to the sea uninterrupted and improve the quality of seawater in the beaches of both Batu Feringghi and Tg Bungah and their surrounding for recreational activities.” – December 8, 2024