Visitors to the Singapore River area may have noticed that two iconic bronze sculptures along the river have gone missing for some time.

The sculptures - named A Great Emporium and From Chettiars To Financiers - were removed 1½ years ago and started undergoing restoration at a workshop last month.

Two others, The River Merchants and The First Generation, are being restored onsite.

The restoration works will be completed by the end of November.

The four pieces are part of the People Of The River sculpture series, consisting of 17 bronze human figures that depict various historical scenes of people who lived and worked along the river.

The series was commissioned in the early 2000s by the Singapore Tourism Board and are cleaned and maintained every three months.

Ms Serene Tan, 38, the tourism board's director of lifestyle precincts development, says: "Due to wear and tear from the weather and human interaction, we have to conduct restoration works to ensure the sculptures are in an optimal condition for enjoyment by visitors."

For the restoration, the board has engaged home-grown materials, architectural and engineering consultancy firm Maek Consulting and Singapore metalworks company Metalworld.

The two sculptures being restored off-site are at Metalworld's workshop in Bedok Industrial Park. In March last year, they were removed to make way for enhancement works in the Civic District.

The floor tiles around the sculptures were hacked away by a specialist contractor, who then removed the pieces, packed them in styrofoam, plastic sheets and Japanese rice paper and sent them to a storage warehouse.

Due to their weight - From Chettiars To Financiers is about 1,000kg and A Great Emporium about 2,100kg - six people were required for the move.

Ms Serene Teoh, 25, a consultant with Maek Consulting, says: "We had to be extra careful because any wrong move might damage the sculptures further."

The condition of the sculptures was assessed using analytical technologies and chemical analysis, and a video scope was used to check their internal condition. Missing parts and areas that require localised repair were identified.

For example, missing from A Great Emporium - which depicts traders negotiating - is a counterweight weighing about 3.5kg. The River Merchants is missing a rope connecting an ox to a cart, which visitors have tugged on when taking photos. Both pieces have to be replaced.

At Metalworld's workshop, craftsmen fill pit holes and cracks using controlled gas welding. Green patina is removed using soft steel wool.

Mr Chua Choon Ling, 48, Metalworld's managing director, says: "One of the challenges is reaching cracks in hard-to-reach areas. At times, my staff have to work while lying on their backs on the floor."

For some areas, a layer of chemical is applied to achieve the sculpture's desired colour. A layer of protective wax is then applied, allowed to dry and the surface buffed.

To minimise future damage, some sculptures will be modified. For example, the rope in The River Merchants will be welded closely onto the ox and cart so that people will not be able to pull it easily.

Such modifications are kept to a minimum, though, and done with care and in consultation with the artist, conservator, consultant and the tourism board to maintain the original artistic integrity. The board declined to reveal the costs.

Each sculpture takes one to two weeks to restore. The sculptures in the workshop will be in new locations - next to the Asian Civilisations Museum - from December.

Ms Tan says: "Singaporeans and visitors can look forward to better photo opportunities as well as new signboards on the inspiration and design behind the sculptures once the restoration is completed.

"The sculptures are created to allow public interaction but, as with all public artworks, we hope that the public will respect and take good care of them."

Watch skilled crafts- men give the bronze sculptures a makeover. Go to str.sg/4Gfy

Life by the river

The People Of The River series of bronze sculptures recreates the real people and history of the Singapore River. These are the stories behind them.

THE RIVER MERCHANTS BY AW TEE HONG (2002)

This sculpture depicts one of Singapore's earliest merchants - Alexander Laurie Johnston - mediating between a Chinese trader and a Malay chief, as labourers load goods onto a bullock cart.

It is located in front of Maybank Tower, where Alexander Laurie Johnston & Co's godown - or warehouse - once stood.

As this location was nearest the river mouth, Johnston could catch the merchants as their longboats entered the river.

THE FIRST GENERATION BY CHEONG FAH CHONG (2000)

Just outside The Fullerton Hotel - and rivalling Colombian artist Fernando Botero's Fat Bird as the most famous sculpture along the river - this work features five naked boys diving off the banks.

The river was once not only a trade route, but also a swimming pool for local kids.

FROM CHETTIARS TO FINANCIERS BY CHERN LIAN SHAN (2001)

This sculpture melds the past and present of Singapore's finance industry. In the early days, the area contained many trading houses and financial businesses.

The moneylending trade was run primarily by people from South India, known as Chettiars. In this sculpture, a Chettiar is flanked by a Chinese clerk of yesteryear and a modern-day finance trader.

From December, it will be located next to the Asian Civilisations Museum (ACM) in Empress Place.

A GREAT EMPORIUM BY MALCOLM KOH (2001)

This work shows a typical scene of the Singapore River in days gone by - a group of traders negotiating the price of a sack of cinnamon.

The sculptor once said this piece was done from memory and is based on his experience.

His father worked in an office in a riverside godown and often took him there.

From December, it will be located next to the ACM.