Rehabilitation of Cultural Landscape: Ancient Hydraulic System

HANG Peou, P. Eng., Dr., Hydraulic & Hydrology

APSARA National Authority

Siem Reap, January 12, 2016 Overview of Angkor cultural landscape

Cultural landscape: Monument, Water & Forest Overview of Angkor cultural landscape

North

East Baray

Angkor Vat Chau Srei Vibol

Lolei Baray

Vat Chet Dei LiDAR 2012 5 km

4 km

27 km

Angkor 13 km

6 km

5 km

Tonlé Sap GIS: Watersheds

Topographical Watersheds: • : 836.74 Km2 • Pourk : 935.62 Km2 • Rolous : 1031.84 Km2

Angkor

Siem Reap city Water and Monuments

Angkor Park need the water, not only for living people inside the protected zones and visitors but also for the Temples!

Temple

Groundwater level

Water play a role very important in the stability of temple especially the groundwater because all the temples in the Angkor Park are built on the sand layer and the resistance of sand is depend on its degree of saturation (water) and the sand layer has direct connection with the groundwater and the Moats. Siem Reap Water Supply • Before 1995: – Small town – Water source from • From 1995: – Increasing of water demand – Limit capacity of Siem Reap river in dry season – Change water source to Groundwater – 1,440 m3/day • In 2005: Groundwater – New Water Treatment Plant of SRWSA with actual 14,000 m3/day – Private wells

Angkor: 130 000 (estimation in 2013) Temple Temple

• Siem Reap: Pumping Machine • Population : 203 483 in 2009 • Tourism : 2 000 000 in 2012 • Projection (JICA 2009) Groundwater level • 2015 : 27,900 m3/j Groundwater level • 2030 : 83,300 m3/j Before After

Rehabilitation of Angkorian water

The moat: structures • moat • Angkor Thom moat • moat • moat

The Baray (reservoir): • (royal basin) • West Baray (11th century) • North Baray (Jayatataka – 12th century)

The North Baray project has four main objectives:  Research on Ancient Hydraulic System that built in 12th century and dry up in 16th century to understand the whole system and refill water to Jayatataka (with dimension 3600 m X 930 m and its original capacity of 5 /10 Mm3).  Restore historical cultural landscape and develop a new support for circuit of visit to attract more tourism to Angkor Park.  Bring more water for local people living in the Angkor Park and give them a model of sharing water between local community and temples in the region, and  Recharge the groundwater to balance an uncontrolled extraction of groundwater in Siem Reap city. Rehabilitation of Jayatataka (North Baray) • North Baray (Jayatataka) – Dimension : 3600m X 930m – Storage : 5/10 Mm3 • Watershed – Surface: 105.27 Km2 – Runoff : 36.84 Mm3 – Base flow : 0 • Storage • 2008 : 700 000 m3 • 2009 : 3 000 000 m3 • 2010 : 3 786 000 m3 • 2011-2015 : 5 000 000 m3 • Recharge ground water • Preah Khan moat • down stream of Baray • Flood control • Villages • Angkor Thom

Rehabilitation of Jayatataka (North Baray)

Neak Peaon

Preah Preah khan2 Kraing Kroch Khan1

December 14th, 2008

21 May 2007 30 Octobre 2008 (209 cm)

24 Décembre 2008 (168 cm) October 17th, 2009

November 28th, 2009

November 20th, 2009

January 6th, 2009

November 20th, 2009 November 9th, 2009 Flood events

Banteay Srei

APSARA Flood in 2009 Flood in 2010 Flood in 2011 Ancient Hydraulic System Without restoration of ancient hydraulic system: • 2009, • 2010, • 2011.  20 M$ for infrastructure Without restoration of Flood in 2012: ancient hydraulic system: • September 3-6th , • 2009, • September 15-18th , • 2010, • September 21-24th and • 2011. • September 29th to October 2nd West Baray

Mebon before flood

Mebon after flood with more than 56 Millions Cubic meters With ancient hydraulic system, we can protect the temples, airport and city center of Siem Reap from flood since 2012:

Flood in 2012: Flood in 2013: nd September 3-6th , August 1-2 , September 15-18th , September 20-28th , September 21-24th and October 2-7th September 29th - October 2nd Future vision

PAAGERA project (-France)

Telemetry : Decission tool

APSARA • Water level • Weather • METEO-SAT/Radar Remote Management

4.PeakAngkromol(1) Sneng road(0) 5.Phlong(4) 1.Spean Thom(6) et 3.Dei Sar(3) Inlet North Baray(4) 2.Spean Thom canal (3)

12.Norkor Krao 9.Dei Chnaing(5) 8.Oulet North Baray(2) Phnom Bauk(2) 6.North-west Angkor Thom(5) Canal A(2) French Weir(1) (1) 7.KOICA road(4) Ta kaov(2) Canal(1) 10.Dead gate(1) Canal 2005(2) 11.TaTa Kaov2(2) Kaov3(2) Ta Promh(2) Tonle Om(2) Outlet West Baray(4) Srah Srang(1) South-west Angkor Thom(1) North Angkor Wat(2) Eat Angkor Wat(2)

APSARA Monument conservation

Angkorian Sustainable Cultural Hydraulic development of landscape system region

Optimization water management & Flood management Thank for your kind attention