Mpala Research Centre Discovery Day 2014

1. Exploring the relationship between
water availability and small-scale
agricultural systems near Mount Kenya
Drew Gower; Advisor: Dr. Kelly Caylor
Department of Civil & Environmental Engineering,
Princeton University

2. Nanyuki Catchment
MRC

3. Hydrologic Variability
Source: Weismann et al., 2000

5. Irrigated Agriculture
• Hydrologic variability offset by irrigation using
river water
• Supports a range of operations from export-
driven large farms to household gardens
producing food for domestic consumption.
• Large farms draw water from the rivers through
separate irrigation systems and are buffered by
boreholes and reservoirs
• Households receive water for irrigation and
domestic use through community water projects

6. Source: Aeshbacher et al., 2005

7. Source: Gichuki, 2004

8. Climate Change Impacts
Source: USGS, 2010

9. Research Questions
• What is the current and past distribution of dry
season irrigation use in the Nanyuki Catchment?
• What populations are currently most dependent
on irrigation use for their livelihoods?
• How might climate change affect water
availability and livelihoods in the Nanyuki
Catchment?
• What factors affect the resilience of dryland
agricultural systems generally?

10. Previous Work
• Conducted weekly flow
measurements in 10 to 20
households in 25 projects
• Consisted of recording the
amount of time needed for
water to fill an 18 liter bucket
• Lasted between 5 and 6
months, depending on the
project
• Also recorded amount and
type of water use at one
household per project

11. 0
10
20
30
40
50
60
70
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
FlowRate(liters/minute)
0
10
20
30
40
50
60
70
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
FlowRate(liters/minute)
Kaga Water Project
Maka Water Project
Source: Paul McCord (Personal Communication)
Week

12. Household and Manager Surveys
• More than 1,050 household-
level surveys on water use,
agricultural practices,
cropping strategies, and
demographic information
• Eighty water project-level
manager surveys on rule
formation, water rotation
strategies, and water project
infrastructure

13. Ongoing Work
• Weekly stream gauging and
isotopic sampling at 10
locations in the Nanyuki
Catchment
• Weekly collection of natural
and agricultural vegetation
samples for isotopic analysis
• Helping projects to upgrade
their master meters to collect
project-level flow information

14. Current Gauge Station
Proposed Gauge Station
MRC

15. Socio-hydrologic Model
Hydrologic
Model
Crop Model
Agent-Based
Model
• Composed of a conceptual
hydrologic model, an agent-based
model and a crop model
• Validated with hydrologic
measurements and distribution of
agricultural yields
• Used to investigate socio-
hydrologic outcomes of climate
and land use change
• Outcomes evaluated by total crop
yield and fraction of users above a
minimum threshold of water
availability

16. Acknowledgements
This research was supported by the National Science Foundation,
Grant No. 1115009. I’d also like to thank the following people for
their advice and assistance:
• Dr. Kelly Caylor (Princeton University)
• Sally Goodman (Princeton University)
• Eliza Harkins (Princeton University)
• John Gitonga (Mpala Research Center)
• Dr. Tom Evans (Indiana University)
• Paul McCord (Indiana University
• Dr. Jampel Dell’Angelo (Indiana University)
• Mengistu Seketedi (Lewa Wildlife Conservancy)
• Linden McBride (Cornell University)

17. Questions?