This is lesson 1 for Three Day Residential Training Workshop on Cascade Water Resources Development and Management prepared for Climate Resilient Integrated Water Management Project Project

1. Three Day Residential Training Workshop on
Cascade Water Resources Development and Management
P.B. Dharmasena
Training Objectives:
After this training, the participants will be able to explain:
 The nature of Tank Cascade Systems in Sri Lanka;
 How the tank cascade system has evolved on dry zone landscape?;
 The important features of tank cascade systems;
 Present status of tank cascade systems in Sri Lanka;
 The contemporary issues found in cascade systems;
 What consequences and constraints experienced by village communities?;
 Why we need to plan water resources development in cascades?
 How we can prepare a water management plan for a cascade?
 Why we need participation of communities in cascade development and management? and
 Roles and responsibilities of implementing partners in cascade development and
management
Lesson 1 - Awareness on ancient tank cascade systems

2. Lesson 1 - Awareness on ancient tank cascade systems
Lesson Objective:
After this training, the participants will be able to explain:
1. The ancient water management master plan in Sri Lanka;
2. Tank cascade system and its evolution on the dry zone landscape;
3. The factors influenced on formation of tank cascade systems; and
4. Zonal distribution of tank cascade systems in Sri Lanka.

3. Topic Description
1 Ancient water management
master plan
Multipurpose water management in ancient Sri Lanka,
Country level, Inter-river basin level, Inter-reservoir
level, Sub-watershed or cascade level, Village level,
Field level
2 Evolution of tank cascade
systems
Hydraulic or water civilization of Sri Lanka, Historical
evidence, Tanks as clusters,
3 Factors influenced on
formation of tank cascade
systems
Rainfall, Landscape, Soil and Geology, Cascade ecology
4 Distribution of tank cascade
systems in Sri Lanka
Distribution of tanks, Cascade zonation
5 Discussion Brain storming
CONTENT
Lesson 1 - Awareness on ancient tank cascade systems

4. Country level
Inter-river basin level
Inter-reservoir level
Sub-watershed level
Village level
Field level
1. Ancient water management master plan
Lets observe these levels one by one ……..

5. Kevesastha (Northern)
Upulwangiri (Kala Oya)
Rakungiri (Malwathu Oya)
Mahagiri (Samanala mountain
area) – Kelani, Kalu, Walawe,
Mahaweli
Chalaka (Mi Oya)
Neelagiri (Modaragam Aru) Kawasthalabha (Yan oya)
Dhumaka Kaddeera (Deduru Oya)
Indra (Maduru Oya, Mundeni
Aru, Gal oya)
Agni (Kumbukkan Oya,
Menik Ganga, Kirindi Oya
Ancient Ten Administrative Divisions based on water (3000 BC)
1. Ancient water management master plan
Country level

6. Sharing water resources in the past
(600 BC – 1200 AD)
• Dambulu Oya - Malwathu
Oya diversion canal (860
AD)
• Malwathu Oya - Kanadara
Oya diversion canal (860
AD)
• Yoda Ela - Nachchduwa
feeder canal (540 AD)
Mahakanadarawa
Nachchaduwa
Kalawewa-
Balaluwewa
Dambulu oya
Malwathu oya
Kanadara oya
Kala Oya
Inter-river basin level
1. Ancient water management master plan

7. – Kalawewa - Thisawewa Yodha
Ela (470 AD)
– Nachchaduwa - Nuwarawewa
feeder canal (290 AD)
– Balaluwewa -
Siyambalangamuwa feeder
canal (290 AD)
– Basawakkulama - Maha
Vilachchiya feeder canal (470
AD) Kalawewa-Balaluwewa
Thisawewa
Siyambalangamuwa
Nachchaduwa
Nuwarawewa
Mahavilachchiya
Basawakkulama
Malwathu oya
Thalawa oya
Kala oya
Sharing water resources in the past
(600 BC – 1200 AD)
Inter-reservoir level
1. Ancient water management master plan

8. Sub-watershed or cascade level
1. Ancient water management master plan
Kendewa sub-watershed
Kapiriggama sub-watershed
Bandara Rathmale sub-watershed

9. 1. Ancient water management master plan
Sub-watershed or Cascade level
Mahakanumulla sub-watershed
Ulagalla sub-watershed
Thirappane sub-watershed

10. 1. Ancient water management master plan
Village level
• Tank bed (wewa)
• Tank bund (we kanda)
• Soil ridge (iswetiya)
• Upstream water hole
(goda wala)
• Upstream tree belt (gas
gommana)
• Rain-fed farms (hena)
• Hamlet (gangoda)
• Downstream interceptor
(kattkaaduwa)
• Hamlet buffer
(tisbambe)
• Paddy field (welyaya)
• Drainage (kiul-ela)
• Shrubland (landa)

11. 1. Ancient water management master plan
Field level
1. Terracing for efficient water management
2. Saving water during land preparation
3. Proper drainage layout to minimize salinity development
4. Rice variety depending upon water availability

12. 1. Ancient water management master plan
Field level
Keta horowwa - Traditional sluice
to control water issues
Karahana – water distribution structure

13. EVOLUTION OF SMALL
AGRICULTURAL SOCIETIES IN SRI LANKA
Three Stages of Evolution
Wild animals
Customs
Natural disasters
External invasions
Primary
Agricultural
Society
Discipline
Traditions
Sharing
Rearing
Farming
Water
Protection
Beliefs
Food Primary
Community Practices
Gathering
Hunting
Secondary
Agricultural
Society
Trading
Industry
Agriculture Culture
Technology
Politics
Kingship - leadership
Transport
2. Tank cascade system and its evolution on the dry zone landscape

14. Network of tanks
and streams
No flood and no
drought
2. Tank cascade system and its evolution on the dry zone landscape

15. Nachchaduwa
Kanadarawewa
Vilachchiya
Kalawewa and
Balaluwewa
Huruluwewa
Main factors:
1. Morphology (landscape)
• Lower elevation,
• Moderate undulation
2. Rainfall
• Bimodality
• ~1500 mm/ year
3. Soil and geology
• Regolith aquifers
• Low infiltration
• RBE – LHG
Network of tanks and streams in the form of cascades
3. Factors influenced on formation of tank cascade systems

16. 4. Zonal distribution of tank cascade systems in Sri Lanka

17. Tank cascades
are found in:
Northern;
North Central;
North Western;
Uva; and
Southern
Provinces
4. Zonal distribution of tank cascade systems in Sri Lanka

18. Tank cascades
are found in:
Mullaitivu;
Vavuniya;
Anuradhapura;
Trincomalee;
Puttalam;
Kurunegala;
Hambantota;
and
Monaragala
4. Zonal distribution of tank cascade systems in Sri Lanka

19. Tank cascades
are found at the
elevation range
of 100-500m
amsl
4. Zonal distribution of tank cascade systems in Sri Lanka

20. Tank cascades
are found in
Specific Agro-
ecological
regions
4. Distribution of tank cascade systems in Sri Lanka

21. Brainstorming Discussion