Last look at Tg. Rimau before slope works begin

A large team surveyed before a 400m stretch of Sentosa Tanjong Rimau will be affected by slope stabilisation work. This shore has among our last natural cliffs with natural rocky shores. And the largest natural meadows of healthy Tape seagrass that remains, since the loss of these in most of our other southern shores.

It was a little challenging to survey in complete darkness. The tide turned at sunrise. The rest of the large team made lots of special finds. I will update with their sightings later.

Tg Rimau has the last best and largest natural meadow of Tape seagrass with long leaves. All Tape seagrasses are now completely gone or severely cropped short on Cyrene, Semakau and the other large southern submerged reefs. Surprisingly, long Tape seagrass is quite abundant on artificial shores like East Coast Park and Eagle Bay (Lazarus Island). Today the Tape seagrasses were still longish (about 30-40cm), some with shorter cropped leaves that stick out of the water. There were a lot of female flowers that had just bloomed, probably the day before, their long white petals still attached but withering. I could see any male flowers floating on the water surface or their bracts at the base of the leaves.

The patch of Sickle seagrass near Rasa Sentosa is still growing lush, leaves not cropped. Throughout the shore there were good sprinkles of Spoon seagrass (small leaves) and Needle seagrass (narrow leaves).

This shore is only one of the two Southern shores where we can see the Critically Endangered Nyireh laut. We probably have less than 10 of these trees on our shores. The mother tree seems okay. Her oldest Daughter no. 1 next to her is still alright. The next younger Daughter no. 2 growing near the pill box is now tall. All three of the trees are distinctly less leafy with bare branches and only a few yellow leaves. Another related species Nyireh batu, seasonally drop all their leaves after turning yellow. I suspect this is what is happening here. Daughter no. 3 which I last saw as a sapling in Apr 2014 has grown really tall and today had fresh green leaves. I couldn't find the small sapling that Nasry found on our last survey in Jan 2026. Hopefully it has been 'rescued' and is now being raised in the plant nursery?

The Critically Endangered Delek air is still doing very well, with lush leafy branches bearing lots of fruits. While the Vulnerable Raffles pitcher plant are still there, though only the crispy parts show up in the photo in the dark. Like many coastal forest plants of Singapore, they are now only found in a few places in Singapore.

I didn't see any signs of work starting, aside from a few poles on the shore, one had fallen over, and another seemed to have propped up a signboard that has separated from the pole. . On a positive note, I'm glad that we have been assured that very large litter will be removed as part of the works.

My thoughts about upcoming works on this shore

Sentosa Development Corporation (SDC) has made a good effort to regularly update and discuss with the nature community on the plans for this shore. We are grateful.  I am glad that slope protection works are being done. Erosion, slope failure and rock slides are a natural aspect of such cliffs. Although these form the picturesque rock formations on the shore that we find so attractive, these can kill also the precious plants and trees that grow here. Here's some photos of ongoing slope failure that I saw on our last survey in Jan 2026.

On other islands like St. John's in the past, the engineering solution was to simply pour a sheet on concrete on the slope. This eliminates any possibility of plants growing back on the slope. The current plan for Tg. Rimau is to create grid beams that will allow plants to continue to grow after stabilising the slope. This seems a far more reasonable approach.

Of most concern are the impact of the working footprint so heavy equipment and materials can be brought to the slope. According to the EIA for the works found that more than 12 per cent of seagrass meadows may be lost. SDC has reassured the community that the working site will be minimised as much as possible, and works monitored to ensure they don't go beyond the site. 

The other worry are the Xblocs: 0.7m (height) × 1.3m (width) × 1.7m (length), weighing 1-tonne each - similar to the photo. "A few hundred" interlocking blocks will be placed “at the toe of the slope to mitigate wave erosion". SDC reassured one reason XblocPlus was chosen was that it assembles more quickly, which shortens the construction impact period. Also, engineers will work to "replicate the structural complexity of existing natural rocky shores, and to support the diversity of intertidal fauna and algal communities already present at Tanjong Rimau."

We wish SDC and team all the best for this well intentioned effort to stabilise Tg. Rimau shores for the future. Works are expected to start soon.

Related blog posts
Sentosa Tg Rimau: EIA on slope stabilisation works Jul 2026
Sentosa Tg. Rimau: Interlocking 1-tonne blocks to be deployed Jun 2026


Photos by others on this survey


Zen Xuan He