1. Aguas
Subterráneas el la
Cordillera Blanca,
Peru
Jeffrey McKenzie (McGill University)
Daniel Chavez (McGill University)
Ryan Gordon (Syracuse University)
Laura Maharaj (McGill University)
Michel Baraer (École de technologie supérieure)
Bryan Mark (The Ohio State University)
Laura Lautz (Syracuse University)

2. Importance of Groundwater in
the Proglacial Zone
Baseflow to Rivers and Streams,
Sustaining Dry Season Flows
Temporal Storage and Release of
Water
Potential Impacts on Water
Quality
Water for Ecological Systems,
such as wetlands

3. Groundwater Questions
1) After peak-water, is groundwater
contribution to water resources
significant?
2) What is the source and flow paths
of groundwater?
3) Can we assess the groundwater
‘residence time’?
4) Is groundwater vulnerable?

4. Pampas – An Important Landform
for groundwater in the Cordillera
Blanca?
(Knox, 2009)
Quilcayhuanca
Yanamarey

5. Downstream Confluence
Hydrochemical mixing models
GlacierizedNon- glacierized
Glacier
No Glacier
YAN
Q3
Q2
Q1
YAN
Q1
Q3
Q2
mixingline
1999 Mix (Q3) = 70% Non-Glacier Water
Q3
Q1
Q2
YAN
Mix
2004 Mix (Q3) = 50% Non-Glacier Water
Mark et al., 2004

6. Hydrochemical Basin
Characterization Method
(HBCM; Baraer et al., 2007)
Yanamarey Watershed

7. HBCM
Dry Season Groundwater in Other Valleys
(1) Llanganuco
(2) Quilcay
(3) Querococha
Baraer et al., 2009
(4) Pachacoto

8. Rain Fed Groundwater Systems
Chavez et al., 2012
Talus
Bedrock
Glaciolacustrine
GPR Results

9. Mixed-Source Groundwater Systems
Llanganuco Upper Pampa, Viewed from Laguna 69

10. Debris
Fan
Talus
Meadow
Moraines
Laguna
69
Lag.
Broggi
Llanganuco Upper Pampa

11. Big spring
82.1 L/s
Flow
from fan
22.8 L/s total
Flow from
Moraine
5.2 L/s
Outflow from
Lag. 69
21.8 L/s
Outflow from
Lag. Broggi
35.8 L/s
Outlet
115 L/s
Discharge
and net
changes
METHOD - Double-slug
dilution gauging method
which provides:
 discharge (Q)
 net change in discharge
(∆Q)
 gross gains and losses
(Qgain and Qloss )
Laura Lautz & Ryan Gordon
Syracuse University

12. Groundwater Travel Time
Geochemical Results
 Travel time is ~ 1.5 to 3 years
Darcy Velocity Calculations
 Groundwater velocity through
talus is ~ 3 mm/d
 Minimum travel time is greater
than 1 year

13. Threats to Groundwater
• Receding glaciers may impact
groundwater recharge in mixed-sourced
aquifers
• Changes in precipitation regime due to
climate change will affect recharge
• Human contamination of groundwater 
Very Difficult to Fix
• Increased ET due to warmer temperatures

14. Conclusions
RECHARGE
Groundwater is
recharged from
precipitation
and glacier melt
STORAGE
Groundwater is
stored over
years in coarse
grained aquifers
RESOURCE
Groundwater is
an important
contributor to
dry season flows
THREATS
Groundwater is
Vulnerable to
Climate Change
and
Contamination
jeffrey.mckenzie@mcgill.ca