ACIAR - Southern Lao Project Water Component

ACIAR - Southern Lao ProjectACIAR - Southern Lao Project Water ComponentWater Component

Participants include:Participants include: Phil Eberbach, Phil Eberbach, Thavone Inthavong, Thavone Inthavong, Ketema Zeleke; Ketema Zeleke; Somsamay Vongthilath, Ruben Lampayan, Ben Samson, Stefan HaefeleSomsamay Vongthilath, Ruben Lampayan, Ben Samson, Stefan HaefelePany Vanmanivong Keo Souvanh, Phouvieng Songseum, Pany Vanmanivong Keo Souvanh, Phouvieng Songseum, Khamma Keovised, Jono NewbyKhamma Keovised, Jono Newby

Wet Wet seasonseason

Dry Dry seasonseason

Rice

Rice Alternate crops or forages

Rainfed – rice Rainfed – rice

Rice breeding for Rice breeding for flood and drought tolerance flood and drought tolerance

– 4.3– 4.3 Supplemental Supplemental irrigated irrigated waterwater

Groundwater – Groundwater – 4.14.1

Farm or community Farm or community ponds 4.1 - 4.2ponds 4.1 - 4.2

Carryover of Carryover of residual water residual water 4.14.1 Water saving strategies – 4.2Water saving strategies – 4.2

Social and economic impact of Social and economic impact of improve access to water -4.4improve access to water -4.4

SLP Water componentSLP Water component

4.1 Water Balance of the Champasak Province4.1 Water Balance of the Champasak Province

Irrigation = Evapotranspiration – rainfall – residual carryover soil water - drainage Irrigation = Evapotranspiration – rainfall – residual carryover soil water - drainage

4.14.1 Assessment of water availability and deficit Assessment of water availability and deficit irrigation for non-rice crops in rainfed region of irrigation for non-rice crops in rainfed region of

Southern Lao PDR Southern Lao PDR •Modelling approach to estimate the probable amount of Modelling approach to estimate the probable amount of residual water remaining at the end of the wet season.residual water remaining at the end of the wet season.•Simplified modelling approach NAFRI/UQ (SWBM) adopted Simplified modelling approach NAFRI/UQ (SWBM) adopted •Apply the output spatiallyApply the output spatially

Start of growing season

End of growing season

Soil data

Clay%

Downward (D) Sat, FC, WP, Air

(Saxton & Rawls)

Climate data

Rainfall ETc

•Point based (daily)Point based (daily)•Gridded surface Gridded surface (weekly)(weekly)

Deficit irrigation recommendation

Assessment of water availability and deficit Assessment of water availability and deficit irrigation for non-rice crops in rainfed region of irrigation for non-rice crops in rainfed region of

Southern Lao PDR Southern Lao PDR

•Need to apply the model spatially in Champasak provinceNeed to apply the model spatially in Champasak province

•Challenged by a lack of spatial rainfall dataChallenged by a lack of spatial rainfall data

• Output of a probabilistic spatial carryover soil-water map Output of a probabilistic spatial carryover soil-water map to advise on irrigation requirementsto advise on irrigation requirements

Photo: T InthavongPhoto: T Inthavong

• Minor amount of groundwater data is available for Savannakhet but there Minor amount of groundwater data is available for Savannakhet but there is a paucity in knowledge of the groundwater associated with the Mekong is a paucity in knowledge of the groundwater associated with the Mekong alluvium in Champasak provincealluvium in Champasak province

•Currently rates of development in Champasak necessitate an Currently rates of development in Champasak necessitate an understanding of the resilience of the system for sustainable managementunderstanding of the resilience of the system for sustainable management

•Current estimates of recharge indicate about 69 – 76 mm of rainfall Current estimates of recharge indicate about 69 – 76 mm of rainfall (about 2-5%) in Savannakhet enters groundwater while in Champasak initial (about 2-5%) in Savannakhet enters groundwater while in Champasak initial estimates indicate up to 15% of rainfall may recharge groundwaterestimates indicate up to 15% of rainfall may recharge groundwater

Photo: K ZelekePhoto: K Zeleke

Boreholes which can be used for groundwater and salinity monitoring for detailed groundwater study in the Soukhouma and Champasak provinces.

0

1

2

3

4

5

6

7

8

9

0 20 40 60 80 100 120 140 160GW level depth (m)

Days after 1 October 2011

Boungkeo

Hieng

Nongnang

Pakor

Samkha

Thadan

Tupchane

As bores are used conjunctively to support households it is difficult to separate domestic pumping fromAs bores are used conjunctively to support households it is difficult to separate domestic pumping frombehaviour of the local groundwater system behaviour of the local groundwater system

4.1 Surface water availability and use from 4.1 Surface water availability and use from farm ponds in southern Laosfarm ponds in southern Laos

Describes the existing uses and management of farm ponds and factors affecting availability

Optimal farm design to utilizing farm dams, and management to optimize water use

Seven dams monitored in Savannakhet and Champasak provinceSeven dams monitored in Savannakhet and Champasak province

Photo: R LampayanPhoto: R Lampayan

Location Water depth (cm)

Max

Current depth*

% remaining

1. Khok Nounbua, Sokhuma 283.8 140.6 49.5

2. Bak, Sokhuma 191.4 74.8 39.1

3. Oparath, Phontone 170.7 84.2 49.3

4. Nasomvang, Phontone 243.2 100.7 41.4

5. Na Chanoa, Outhompone 226.8 140.8 62.1

6. Phin Nuang, Othompone 192.0 95.4 49.7

7. Champone 189.2 73.9 39.1*Current water depth as of Jan 30, 2012

Maximum and current pond water depths for 7 ponds

0.0

50.0

100.0

150.0

200.0

250.0

300.0Ponding depth (cm) Pond No. 1 (Khok Nounbua, Sokhuma)

0

50

100

150

200

250Ponding depth (cm) Pond No. 2 (Bak Village, Sokhuma)

020406080

100120140160180

Ponding depth (cm) Pond No 3 (Oparath Village, Phontone)

0

50

100

150

200

250

300Ponding depth (cm) Pond No 4 (Nasomvang Village, Phontone)

VillageVillageChampasakChampasak

Have pond Have pond (% of HH (% of HH

surveyed)surveyed)Pond has water Pond has water

all year all year Use for NurseryUse for NurseryUse for Use for

Crop/VegCrop/VegPhalingPhaling 10%10% 67%67% 33%33% 0%0%OupalathOupalath 43%43% 69%69% 23%23% 62%62%NonePhajaoNonePhajao 17%17% 20%20% 0%0% 0%0%BoungkeoBoungkeo 27%27% 100%100% 25%25% 25%25%KhokeNongbuaKhokeNongbua 13%13% 100%100% 0%0% 25%25%HiengHieng 3%3% 0%0% 0%0% 0%0%TotalTotal 19%19% 71%71% 18%18% 32%32%

4.2 On farm trials of integrated water saving and water 4.2 On farm trials of integrated water saving and water productivity to secure WS rice and secure DS productivity to secure WS rice and secure DS crop/fodder optioncrop/fodder option

Alternate Wetting and Drying Dry season rice Alternate Wetting and Drying Dry season rice productionproduction

-Evidence suggests -Evidence suggests substantial water substantial water savings are possiblysavings are possibly

- Yield appears - Yield appears largely unaffected largely unaffected

-20

-15

-10

-5

0

5

10

15 FP

AWD

Field water depth (cm)Soukuma, 2011 DS

Photo: R LampayanPhoto: R Lampayan

4.3 Agronomic evaluations and dissemination of new 4.3 Agronomic evaluations and dissemination of new drought rice varietiesdrought rice varieties Early wet season droughts commonly affect WS Early wet season droughts commonly affect WS

rice crops in Laorice crops in Lao Drought tolerant lines Drought tolerant lines

developed by IRRI developed by IRRI have been tested in have been tested in Lao and shown Lao and shown enhance rice survival enhance rice survival during early rainless during early rainless periodsperiods

Photo: S HaefelePhoto: S Haefele

Improve the understanding the nature of water sources in Lao and of the relationship between Lao people and these sources of water

4.4 Strengthen community water management schemes 4.4 Strengthen community water management schemes and adoption of water-saving technologies at the system and adoption of water-saving technologies at the system or community levelor community level

Photos: Jono NewbyPhotos: Jono Newby