Work to start on extension to Botanic Gardens

Grace Chua Straits Times 4 Mar 13;

ALONG Tyersall Avenue, just off Holland Road, stands a set of spiked, forbidding-looking gates.

Inside, the paved path is buried under moss and just visible under a thick carpet of fallen leaves and fruit. The area is overgrown with trees such as tembusu, banana and albizia.

But in a few years' time, visitors to the Botanic Gardens will get to wander through this forest and a new marshland on an elevated walkway, perhaps even at night when the area comes alive with a chorus of creatures.

This 9.8ha patch, about as big as some 12 football fields and once part of the estate of the late Sultan Abu Bakar of Johor, will be the latest extension to the Botanic Gardens.

The forested area will bring the total size of the 154-year-old Botanic Gardens to nearly 74ha.

This year, work will begin on the long-delayed project, called the Tyersall extension. It was first announced in 2009, but in 2011, the completion date was extended from last year to this year. Now, work is slated to be done in 2015.

Singapore Botanic Gardens director Nigel Taylor said plans and specifications for a stormwater detention pond under a parking area for buses and cars at the Tyersall extension had to be finalised with PUB, the national water agency.

The century-old, regenerated forest of the Tyersall extension provides a rare chance to study forest regrowth, Dr Taylor added. "That's an interesting message: If you leave nature to get on with itself, in some cases, it can recover," said the botanist and former head curator of the Royal Botanic Gardens at Kew in London.

Within the forest patch are towering tembusu trees planted along the entry path to the Istana Tyersall, the Sultan's residence here which burned down in 1905.

It is likely that these, along with other plants and fungi, enabled the forest to regenerate, Dr Taylor said. A 6ha rainforest pocket at the main Botanic Gardens was also a likely source of fruit and seeds that were transported by birds.

Most of the biodiversity will be left undisturbed, he said. While invasive species like oil palm and some types of yam will have to be cleared, others like passion fruit, pili nuts and other medicinal herbs will stay.

Botanic Gardens staff even found a species of the rare Nipis Kulit tree, which was thought to have vanished from Singapore, in the forest.

The Tyersall extension will also feature a new freshwater swamp forest habitat. Elevated walkways will serve to protect both visitors and biodiversity.

Tyersall Avenue will also be realigned to skirt the edge of the extension. Dr Taylor did not disclose how much the project will cost since that will depend on tender results. Singapore Press Holdings is giving $1.2 million to develop outreach programmes.

"Man has so altered the environment that if you want a natural or semi-natural environment to prosper, you have to manage it," Dr Taylor said.

Botanic Gardens' Tyersall site dates back to 1854
Grace Chua Straits Times 4 Mar 13;

THE Singapore Botanic Gardens' Tyersall extension, which will feature tropical forest and marsh habitats, towering tembusu trees and an aerial walkway when it is completed, has a long history.

The 9.8ha is part of a larger 24.4ha swathe which was first occupied by lawyer and newspaper editor William Napier who, in 1854, built a house on it named Tyersall.

Later, the area became the estate of the Sultanate of Johor.

Sultan Abu Bakar built the Istana Tyersall, his Singapore residence, on it, as well as Woodneuk, a house which he gave to his wife Khadijah.

The Istana Tyersall was lost in a fire in 1905 and the land fell into disuse.

In 1990, the Government first announced plans to acquire a slice of the site. Today, the 9.8ha strip is under the Singapore Botanic Gardens' purview, while a larger plot to the west, bordering Holland Road, is private land.

The extension was first announced by then National Development Minister Mah Bow Tan in 2009, but its completion date was pushed back from 2012 to this year and now to 2015, as plans for a stormwater detention pond had to be worked out. Work will begin on the project later this year.

The new Botanic Gardens extension will do double duty as a visitor attraction and flood protection facility: Under its carpark for coaches and cars will sit a detention pond to protect the Stamford Canal catchment area from flooding during heavy storms.

The pond, with the capacity of some 15 Olympic-size pools, will hold excess stormwater temporarily to protect flood-prone areas.

When it rains, water from the catchment area will be channelled into the pond before it is released later into Marina Reservoir via Holland Road drains, a diversion canal and the Singapore River.

Finally, when the Tyersall extension takes shape, it will be part of a green network that extends north to the Central Catchment reserve and includes residents' gardens and community planting in Kheam Hock Road, and that will allow birds and butterflies to move in an ecological corridor.