Managing Stormwater for Water Resource and Flood Control Tan Tien Ser Assistant Director Catchment & Waterways Department Public Utilities Board, Singapore

Managing the complete water cycle Rain Sea PUB is responsible for the sourcing, collection, purification and supply of drinking water, the treatment of used water and turning it into NEWater, as well as drainage of stormwater Desal Water NEWater NEWater Indirect Potable Use Direct Non-Potable Use

Integrating the Water Loop : Water for All

Half of Singapore already serves as a water catchment Catchment area will be increased to two-thirds by 2009 when new schemes are completed 1. Water from Local Catchment Punggol Reservoir Serangoon Reservoir Marina Reservoir Punggol Reservoir Marina Reservoir

Half of Singapore already serves as a water catchment

Catchment area will be increased to two-thirds by 2009 when new schemes are completed

INLAND RESERVOIRS ESTUARINE RESERVOIRS Poyan/Tengeh STORM WATER COLLECTION POND Tampines Pond B MacRitchie

2. Imported Water from Johor Two water agreements with Johor, Malaysia 1961 to 2011 1962 to 2061 State of Johor, Malaysia PUB pipelines carrying water from Johor

Two water agreements with Johor, Malaysia

1961 to 2011

1962 to 2061

Treated Used Water Reverse Osmosis 3. NEWater: Reclaimed Treated Used Water NEWater Microfiltration Ultra-Violet

NEWater: Fast Expanding Kranji (9 mgd, Jan 2003) Seletar (5 mgd, 2004) Bedok (7 mgd, Jan 2003) Ulu Pandan (32 mgd, Mar 2007)

4. Desalinated Water To augment and diversify our water resources At 30 mgd ( 136, 000 m 3 /d ), it is one of the largest seawater RO plants Opened by the Prime Minister on 13 Sep 05 Opening Ceremony Desalination Works Desalination Membranes Chemical Storage Silos

To augment and diversify our water resources

At 30 mgd ( 136, 000 m 3 /d ), it is one of the largest seawater RO plants

Opened by the Prime Minister on 13 Sep 05

Flood control aspect of Singapore’s Urban Management High rainfall and dense urbanization in 1970s and 1980s Singapore led to frequent urban flooding Exacerbated by high tides (3+m tide range) and low lying coastal areas Singapore has had an ongoing effort since the later 1960s to build an effective storm drainage network This is fully integrated with the development of “new towns” which today house much of the population This has been very successful – with flood prone areas reduced to less than 100 hectares (and with limited flood depths)

High rainfall and dense urbanization in 1970s and 1980s Singapore led to frequent urban flooding

Exacerbated by high tides (3+m tide range) and low lying coastal areas

Singapore has had an ongoing effort since the later 1960s to build an effective storm drainage network

This is fully integrated with the development of “new towns” which today house much of the population

This has been very successful – with flood prone areas reduced to less than 100 hectares (and with limited flood depths)

Flood Prone Areas

annual rainfall of around 2350mm 2 main seasons dictated by monsoons northeast monsoon (Nov to Mar) southwest monsoon (May to Sep) Physical conditions affecting drainage in Singapore island generally flat with pockets of low lying areas affected by high tides increased stormwater runoff from urbanisation 241.8 163.8 184.6 179.2 171.1 163.0 159.3 171.0 176.2 194.0 253.9 285.3 Amount of Rainfall (mm)

annual rainfall of around 2350mm

2 main seasons dictated by monsoons

northeast monsoon (Nov to Mar)

southwest monsoon (May to Sep)

island generally flat with pockets of low lying areas

affected by high tides

increased stormwater runoff from urbanisation

Past major floods in Singapore Dec 1978 1,000 people affected 7 people died Tide level = 3.2m Total flooded area = 3178 ha Dec 1969 3,000 people affected 5 people died Tide level = 3.2m Total flooded area = 2750 ha Dec 1954 50,000 people affected 5 people died Tide level = 3.2m Total flooded area = 2540 ha 326 467 512 No Record Dec 2006 8 nurseries, 29 families, 1 club house & 4 shophouses Tide level = 3.0m Total flooded area = 12 ha 366 Amount of Rainfall (mm) Year 1931 1940 1950 1960 1970 1980 1990 2000 2006 0 100 200 300 400 500 600

3200 ha in the 1970’s Braddell Road, Dec 1978 Past Floods Newton Circus, Dec 1969 Braddell Road, Dec 1978 Bideford Road, Dec 1969 Flood Photo 1954 Flood Photo 1954 Orchard Road, Dec 1954 Potong Pasir, Dec 1954

Recent Floods Beng Wan Road (4 Apr 05) Jurong Port Road (17 Apr 06) Pasir Ris Farmway 2 (16 Oct 05) Veerasamy Road (13 Apr 07) Commonwealth Ave (18 Jan 07) Bedok Ave 3 (14 Apr 06)

Strategies to prevent and alleviate floods Drainage master planning and development control maintain and update the drainage master plans in tandem with land developments ensure that proper and adequate drainage facilities are provided to serve new developments (ii) Drainage improvement projects ensure that drains and canals are upgraded in time to serve new developments remove constrictions in old drains/canals (iii) Maintenance & enforcement programme

Drainage master planning and development control

maintain and update the drainage master plans in tandem with land developments

ensure that proper and adequate drainage facilities are provided to serve new developments

(ii) Drainage improvement projects

ensure that drains and canals are upgraded in time to serve new developments

remove constrictions in old drains/canals

(iii) Maintenance & enforcement programme

Canal Outlet drain Closed roadside drain Open roadside drain River Types of drains/canals 820 ha safeguarded for drains and canals (excludes roadside drains within road reserves)

flood protection measures… working with developing agencies….. Commonwealth Ave/Queensway Interchange Jurong Island Complex Crest protection for MRT Clarke Quay Station 1.0m Crest Higher platform level for wafer fabrication plants

Bukit Timah Phase 2A Flood Alleviation 3 1 2 1 2 3 2 1 3 4 2 1 3 4 Newton Circus , 13 May 1988 Bukit Timah Rd / Evans Rd, 13 May 1988 Thomson Road , 3 Dec 1978

Reservoir in the city – Marina Barrage Marina Barrage – 3-in-1 project Flood alleviation – to act as a tidal barrier to control floods in the city Water supply – to be a freshwater reservoir Lifestyle attraction – vibrant waterfront with water based activities Vision … an exciting & vibrant waterfront Completed . . .

Flood alleviation – to act as a tidal barrier to control floods in the city

Water supply – to be a freshwater reservoir

Lifestyle attraction – vibrant waterfront with water based activities

Marina Barrage … further reduce flood-prone areas Low-lying areas in Chinatown, Jalan Besar, Rochor will be protected Marina Barrage

TNP Big Walk 2008 at Marina Barrage (2 Nov 08)

Blue Map of Singapore 14 reservoirs 32 major rivers 7,000+km of waterways

14 reservoirs

32 major rivers

7,000+km of waterways

Active Beautiful Clean (ABC) Waters Programme Long-term initiative by PUB to transform our utilitarian concrete drains, canals and reservoirs into vibrant, aesthetically pleasing and clean flowing streams, rivers and lakes “… Turn Singapore into a City of Gardens and Water” – PM Lee, ABC Waters Public Exhibition - Feb 2007

Long-term initiative by PUB to transform our utilitarian concrete drains, canals and reservoirs into vibrant, aesthetically pleasing and clean flowing streams, rivers and lakes

ACTIVE Beautiful & Clean Providing new community space Bringing people closer to our waters Active Beautiful Clean (ABC) Waters Programme

ACTIVE Beautiful & Clean

Providing new community space

Bringing people closer to our waters

Active BEAUTIFUL & Clean Integrating reservoirs and waterways with the urban landscape Creating aesthetically pleasing lifestyle attractions Active Beautiful Clean (ABC) Waters Programme

Active BEAUTIFUL & Clean

Integrating reservoirs and waterways with the urban landscape

Creating aesthetically pleasing lifestyle attractions

Active Beautiful & CLEAN - Improving water quality - Cultivating environmental responsibility among people Active Beautiful Clean (ABC) Waters Programme

Active Beautiful & CLEAN

- Improving water quality

- Cultivating environmental responsibility among people

The ABC Waters Master Plan WESTERN CENTRAL EASTERN 28 projects over the next 5 years Over 100 projects in the long term

28 projects over the next 5 years

Over 100 projects in the long term

Kolam Ayer ABC Waterfront Before

Bedok Reservoir Car park Seating Gallery Floating Gallery - decks and stage

Bedok Reservoir ABC Waters Project Features Landscaping Floating deck with performance stage and fishing deck Viewing galleries on reservoir banks

Features

Landscaping

Floating deck with performance stage and fishing deck

Viewing galleries on reservoir banks

Facilities @ Bedok Reservoir

Sengkang Floating Island

Sengkang Floating Island Artist’s Impressions Today A floating boardwalk camouflaged by plants connects the island and the fruit park A fixed bridge connecting floating island to the Anchorvale CC The floating island helps to filter water while providing an interesting transition from the community club to the fruit park

Sengkang Floating Island Artist’s Impression Fruit-themed pavilion creates a thematic link to the fruit park

Thank You