19 April 2026 · Bishan · Ang Mo Kio · 6.1 km · 92 min · 30°C, bright, water high after Thursday's rain
The River They Put Back
For most of my childhood the Kallang River through Bishan was a straight concrete channel with a fence on both sides. It did its job. Water came in at one end during a storm and left at the other, fast, and nobody was expected to have feelings about it.
Between 2009 and 2012 that channel was demolished and the river was rebuilt as a river: about three kilometres of it, winding, with sloped banks planted to hold the soil instead of walls to contain it. It was done under the ABC Waters programme, the national programme for turning drains and reservoirs into places people actually go.
The engineering is the point
What I like about it professionally is that it is not decoration. The banks are held by plants, coir rolls and rock — soil bioengineering — and the park itself is the flood plain. On a dry day children stand in the shallows. After heavy rain upstream the same ground is under water by design, and there are warning lights and sirens to move people off it in time.
- The banks are held by plants and coir rolls, not walls.
- The park floods on purpose when the river rises.
- Warning lights and sirens clear the low ground in time.
- Cleansing biotopes filter the water on the way through.
That is a genuinely uncomfortable idea to sell to a public: we have built you a park that will sometimes be a river. It works because the timing is managed and the signage is unambiguous.
The otters
The smooth-coated otters arrived on their own, a few years after the park reopened. They are not a landscaping feature. They are a wild family that decided the new banks were good for denning and the restocked water was good for fishing, and they have since become the most photographed residents of the town.
I did not see them. I have seen them exactly twice in four years of walking here, both times at an hour I do not normally keep. What I saw instead was a heron standing in the meander doing nothing at all, for the entire eleven minutes I watched it.
6.1 km along the water, 92 minutes with stops, ending at Ang Mo Kio Avenue 1 where the park stops being a park and goes back to being a drain.