Groundwater and wetlands in La Cienega area —
Santa Fe County, New Mexico
Peggy Johnson
Presentation by Stacy Timmons
December, 2012
New Mexico Bureau of Geology & Mineral Resources, A Division of New Mexico Tech
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Project team
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NM Bureau of Geology/NM Tech: Peggy
Johnson (P.I., hydrogeology, geochemistry,
conceptual model for springs) Dan Koning
(geologic mapping, geologic model), Stacy
Timmons (field team leader), Kitty Pokorny (field
support, database), Brigitte Felix (GIS/graphics)
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NM Office of State Engineer: Laura Petronis
(stream gaging, regional hydrology)
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NM Environment Dept: Maryann McGraw
(wetlands)
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Ecotone /J.W. Jansens: Community outreach,
technical oversight
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Funding: NM Bureau of Geology Aquifer Mapping
Program, Healy Foundation, US Environmental
Protection Agency
New Mexico Bureau of Geology & Mineral Resources
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Wetland hydrology
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Water Budget: Wetlands and uplands
continually receive or lose water
through exchange with the atmosphere,
streams and groundwater
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How water budget components interact
are unique to each wetland
La Cienega wetlands:
 Groundwater in, surface water out
 Evapotranspiration
 Favorable geologic setting
 Adequate and persistent water supply
Project covers surface water outflow,
ET, geology, and source/age of inflow
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“The formation, persistence, size and function of wetlands
are controlled by hydrologic processes. Distribution and
differences in wetlands … are caused primarily by geology,
topography, and climate.” V. Carter, 1996, in USGS Water-Supply
Paper 2425
New Mexico Bureau of Geology & Mineral Resources
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Geologic setting of southern Española Basin
22-14 MY
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Erosion of highlands form Tesuque Formation – Santa Fe Group aquifer
Older volcanic-derived sediments line the bottom of the basin – Espinaso Fm
14-3 MY erosion forms unconformity
2.8 MY deposition of Ancha gravels begins
New Mexico Bureau of Geology & Mineral Resources
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Geology &
hydrology
New Mexico Bureau of Geology & Mineral Resources
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Subsurface geology
New Mexico Bureau of Geology & Mineral Resources
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Base of the Ancha
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Valleys, ridges, topography
on pre-Ancha land surface
Paleo drainages
 El Dorado
 Ancestral Santa Fe River
High Tesuque surface
 Between Cieneguilla and
Arroyo Hondo
 Floodplain and lake
deposits, low K
 Significant feature 150 ft
above adjacent ancestral
Santa Fe River paleovalley
New Mexico Bureau of Geology & Mineral Resources
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Saturation in the
Ancha Formation
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Thick zones east of La
Cienega correlate to areas
of paleo-valley fill
Springs discharge from
Ancha Fm
 Contact with underlying
strata (north slope of Guicu
Creek, Las Lagunitas)
 Incised drainage (Cienega
Creek, Arroyo Hondo)
Paleo-valleys control
elevation of discharge and
location of wetlands
New Mexico Bureau of Geology & Mineral Resources
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Springs and
wetlands discharge
from Ancha
New Mexico Bureau of Geology & Mineral Resources
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Paleo-valleys and paleo-topography
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Existence of paleo-valleys first recognized by Z. Spiegel (1963)
El Dorado and Ancestral Santa Fe River paleo-valleys
Springs and wetlands associated with Ancha paleo-valleys
New Mexico Bureau of Geology & Mineral Resources
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Local watertable surface
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2012 groundwater
conditions for Santa Fe
Group aquifer
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22 spring elevations and
45 wells measured winter
2012
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Used existing data from
29 wells measured
between 1997 and 2007 to
fill data gaps
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Hydraulic gradient east
(6180) to west (5860)
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Water table mound
beneath Santa Fe River
New Mexico Bureau of Geology & Mineral Resources
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Groundwater
flow directions
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Horizontal flow direction
perpendicular to
contours
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Regional flow from east
to west toward Rio
Grande and Santa Fe
River
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Local flow direction
varies – recharge from
or discharge to streams
or arroyos
New Mexico Bureau of Geology & Mineral Resources
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Recharge, discharge,
losing and gaining
streams
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Recharge: downstream
deflection of contours
 Losing stream reach
 Santa Fe River and upper
Arroyo Hondo
Discharge: upstream
deflection of contours
 Gaining stream reach
 Cienega Creek, Arroyo
Hondo, Guicu Creek,
Canorita de las Bacas
Wetlands are groundwater
discharge zones
L. Petronis & J.Veenhuis, 2012
New Mexico Bureau of Geology & Mineral Resources
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Wetlands and seasonal
water-table fluctuations
Winter
Seasonal water-table fluctuations
controlled by precipitation and
evapotranspiration (ET)
▶ Fall-Winter rise = ET decrease
▶ Spring-summer drop = ET increase
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Spring
Summer
4/24/2012
LC-025
Leonora Curtin
kiosk well
Fall
New Mexico Bureau of Geology & Mineral Resources
V. Carter, 1996
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Seasonal water-level
changes – summer/fall
2011 to winter 2012
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Two measurements in 38 wells
Winter increase (0.04 to 6.60 ft) in
84% (32 of 38) of wells
 Average WL rise 0.77 ft
 Wells in or adjacent to wetlands
or in drainages upstream of
wetlands
 Consistent with drop in ET
Winter decline (-0.13 to -0.50 ft) in
6 wells
 Wells located in dry uplands with
depth to water > 100 ft
 Change independent of ET
New Mexico Bureau of Geology & Mineral Resources
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Hydrographs
-0.25 feet/year
-0.11 feet/year
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-0.32 feet/year
-0.14 feet/year
-0.29 feet/year
Persistent trend of declining water levels
EB-220, 10 feet in 40 yrs (0.25 ft/yr)
EB-338 and EB-607, high frequency shows seasonal changes superimposed
on long-term decline
New Mexico Bureau of Geology & Mineral Resources
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Piper diagram
Indicates cation
exchange and
groundwater evolution
▶ Deeper wells with higher
Na
▶ Shallow wells, near
streams have lower Na,
higher Ca
▶ Wells and springs with
mixture of deep and
shallow sources
 Upper La Cienega
Creek and Guicu
Creek
 Arroyo Hondo
 Las Golondrinas
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New Mexico Bureau of Geology & Mineral Resources
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Isotopic
data
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Deep wells – less than -95 ‰ deuterium
Shallow wells and springs -86.5 to -74.7 ‰ deuterium
Springs have undergone evaporation
Isotopic differences in wetland zones are similar to ion chemistry
 More depleted in Arroyo Hondo and Las Golondrinas
New Mexico Bureau of Geology & Mineral Resources
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Contoured apparent 14C
ages and tritium
concentrations
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Apparent 14C ages range from
10,780 to 1,550 years before
present
Tritium ranges from <0.1 to 1.73
tritium units
Oldest groundwater is away
from streams and arroyos
Recharge from streams is
indicated in Cienega Creek and
downstream of WWTP
West slopes of lower Cienega
Creek have slightly older
mixtures of groundwater
New Mexico Bureau of Geology & Mineral Resources
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Mixing groundwater from different flowpaths
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Older deeper waters with high Na, depleted isotopic signature, older apparent 14C
age and no detectable tritium
Shallow waters along drainages have higher Ca, lower Na, more enriched
isotopic signature, younger apparent 14C , and higher tritium levels
V. Carter, 1996
New Mexico Bureau of Geology & Mineral Resources
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Geologic controls
on La Cienega
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Springs discharge from
Ancha Formation
Paleo-valleys control
discharge locations
 Ancecstral Santa Fe
River
 El Dorado paleovalley
Edge of basin and
thinning of Ancha
Formation
New Mexico Bureau of Geology & Mineral Resources
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Summary
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Locations of springs and
wetlands are controlled by
geology
Seasonal water-level changes in
vicinity of wetlands show typical
pattern of winter rise and summer
decline associated with
evapotranspiration
Progressive long-term water-level
declines are consistent with
regional groundwater pumping
and development
Ion chemistry, isotopic data and
age dating methods indicate a mix
of shallow and deep sources of
groundwater to La Cienega region
Findings can help direct future
restoration plans
New Mexico Bureau of Geology & Mineral Resources
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