Climate and Water Monitoring at Carlsbad Caverns National Park: Water Year 2024

Kristina Fahey, Kara Raymond, Tani Hubbard

Please cite this publication as:

Fahey, K., K. Raymond, and T. Hubbard. 2026. Climate and Water Monitoring at Carlsbad Caverns National Park: Water Year 2024. Science Report NPS/SR—2026/484. National Park Service, Fort Collins, Colorado. https://doi.org/10.36967/2318793

Abstract

The Chihuahuan Desert Inventory and Monitoring Network monitors climate and six springs each year at Carlsbad Caverns National Park, New Mexico. We report on climate and water resources together because surface water conditions are closely related to climate conditions. Climate data, including temperature, precipitation, and reconnaissance drought index, are retrieved from The Climate Analyzer (climateanalyzer.org). We assess the condition of each spring, measure spring discharge and wetted extent (area that contained water), collect core water quality and water chemistry data, note the wetland plants and invasive plants and animals present, and sample for environmental DNA (eDNA) to inventory springs for rare species, invasive species, and pathogens. Each spring is somewhat unique, and New Mexico has not adopted water quality standards that apply across the diversity of springs in the state. Therefore, we continue to collect water quality data at the springs to form a baseline reference of natural variance. There was less rainfall than average across WY2024, though October was very wet. The drought index indicated the park was drier than average for the third consecutive year. Overall, high and low temperatures were above normal, but highs varied by month. Wetted area was similar to prior years at all springs except Oak Spring where the springbrook was much shorter than previously measured, and the plunge pool was completely dry. Upper Lowe Ranch Spring has been wet year round since July of 2022, though one orifice was completely dry during the March 2024 visit. Rabbitsfoot grass, an invasive plant, was observed for the first time at Iron Pipe Seep. At Slaughter Pot Hole, Upper East Grammer Spring, and Upper Lowe Ranch Spring, we detected invasive Lehmann lovegrass for the first time. None of our eDNA target species were detected at any spring.

Desert grasses and shrubs on top of flat-topped mountains under wispy clouds.
Carlsbad Caverns National Park landscape.

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Overview

Together, climate and hydrology shape ecosystems and the services they provide, particularly in arid and semi-arid ecosystems. Understanding changes in climate and surface water is key to assessing the condition of park natural resources—and often, cultural resources.

At Carlsbad Caverns National Park (Figure 1), Chihuahuan Desert Inventory and Monitoring Network scientists study how ecosystems may be changing by taking measurements of key resources, or “vital signs,” year after year—much as a doctor keeps track of a patient’s vital signs. This long-term ecological monitoring provides early warning of potential resource problems, allowing managers to mitigate them before they become worse. At Carlsbad Caverns National Park, we monitor climate and springs, among other vital signs. Surface water conditions are closely related to climate conditions. Because they are better understood together, we report on climate in conjunction with water resources. Reporting is by water year (WY), which begins in October of the previous calendar year and goes through September of the water year (e.g., WY2024 runs from October 2023 through September 2024). In this report, we present the results of climate and springs monitoring at Carlsbad Caverns National Park in WY2024.

Figure 1. Map showing a weather station in the northeastern part of the park.
Figure 1. Monitored weather station at Carlsbad Caverns National Park.

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Climate and Weather

There is often confusion over the terms “weather” and “climate.” In short, weather describes short-term meteorological conditions (e.g., it’s currently raining or snowing, it’s a hot or frigid day), and climate reflects patterns of weather at a given place over longer periods of time (seasons to years). Climate is the primary driver of ecological processes on Earth. Climate and weather information provide context for understanding the status or condition of other park resources.

Methods

A National Oceanic and Atmospheric Administration Cooperative Observer Program (NOAA COOP) weather station (Carlsbad Caverns #291480) has been operational at Carlsbad Caverns National Park since 1935 (see Figure 1). This station typically provides a reliable climate dataset, but in WY2024 it was missing data on 81 days. As a substitute, climate analyses in this report use WY2024 and 30-year averages (1991–2020) of gridded surface meteorological (GRIDMET) data from the location of the station. Subsequent reports may revert to the weather station as the data source depending on future data quality.

GRIDMET is a spatial climate dataset (4-kilometer resolution) that is interpolated using weather station data, topography, and other observational and modeled land surface data. Temperature and precipitation estimated from GRIDMET may vary from actual weather at a particular location depending on the availability of weather station data and the difference in elevation between the location of interest and that assigned to a grid cell. Data from both the weather station and GRIDMET are accessible through The Climate Analyzer.

Results

Precipitation and Air Temperature

Highlights: It was drier than average across the year, except for a very wet October. Overall, high and low temperatures were above normal, but highs varied by month.

Annual precipitation at Carlsbad Caverns National Park in WY2024 was 10.13″ (25.73 cm), 4.58″ (11.63 cm) less than the 1991–2020 annual average. The October precipitation total (Figure 2) was approximately twice the 1991–2020 average. All other months were drier than average. The largest monthly precipitation deficits relative to average occurred in May and September, which had 1.24″ (3.15 cm) and 1.58″ (4.01 cm) less rain than average, respectively (Figure 2). The mean annual maximum temperature in WY2024 was 75.7°F (24.3°C), 0.1°F (0.1°C) above the 1991–2020 average. The mean annual minimum temperature in WY2024 was 55.0°F (12.8°C), 3.8°F (2.1°C) above average. Mean monthly maximum and minimum temperatures in WY2024 differed by as much as 5.9°F (3.3°C; see August as an example) relative to the 1991–2020 monthly averages (Figure 2). Mean monthly maximum temperatures oscillated above and below the 30-year averages all year. Mean monthly minimum temperatures were warmer than average in every month except January.

Figure 2. Climogram showing precipitation totals for WY2024 are lower than those for 1991–2020 in every month except October. Maximum temperatures for WY2024 fluctuate above and below those for 1991–2020. Minimum temperatures for WY2024 are higher than those for 1991–2020 in every month except January.
Figure 2. Climogram showing monthly precipitation and mean maximum and minimum air temperatures in water year (WY) 2024 and the 1991–2020 averages at Carlsbad Caverns weather station, Carlsbad Caverns National Park. Data source: GRIDMET via The Climate Analyzer (climateanalyzer.org).

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Drought

Highlight: The park was drier than average for the third consecutive year.

Reconnaissance drought index (Tsakiris and Vangelis 2005) provides a measure of drought severity and extent relative to the long-term climate. It is based on the ratio of average precipitation to average potential evapotranspiration (the amount of water loss that would occur from evaporation and plant transpiration if the water supply was unlimited) over short periods of time (seasons to years). The reconnaissance drought index for Carlsbad Caverns National Park indicates that WY2024 was drier than the 1991–2024 average for the third consecutive year from the perspective of both precipitation and potential evapotranspiration (Figure 3).

Figure 3. Bar graph showing conditions were drier than average since water year 2022.
Figure 3. Reconnaissance drought index for Carlsbad Caverns National Park, water years (WY) 1991–2024. Drought index calculations are relative to the time period selected (1990–2024). Choosing a different set of start/end points may produce different results. Data source: The Climate Analyzer; climateanalyzer.org.

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Springs

Background

Springs, seeps, and tinajas (discrete pools in a rock basin or impoundments in bedrock) are small, relatively rare biodiversity hotspots in arid lands. They are the primary connection between groundwater and surface water and are important water sources for plants and animals. For springs, the most important questions we ask are about persistence (How long was there water in the spring?) and water quantity (How much water was in the spring?). WY2024 springs sampling at Carlsbad Caverns National Park occurred between 03 March and 18 March 2024. Water persistence is monitored continuously throughout the water year, but in this report, we only present WY2024 persistence data up to the sampling visit date for each spring.

Methods

Chihuahuan Desert Network springs monitoring is organized into the four modules described below (see McIntyre et al. 2018 for additional details) and eDNA inventories. All data have undergone certification processes to ensure they have been verified and validated for accuracy, are complete, and are fully documented. Data used in this report are available to park staff on the NPS DataStore and can be provided upon request.

Site Characterization

This module provides context for interpreting change in the other modules. We record GPS locations, draw a site diagram, and describe the spring type (e.g., helocrene, limnocrene, rheocrene, or tinaja) and its associated vegetation in this module. Helocrene springs emerge as low-gradient wetlands, limnocrene springs emerge as pools, and rheocrene springs emerge as flowing streams. This module is completed once every five years or after significant events.

Site Condition

We estimate the level of natural and anthropogenic disturbances and the level of stress on vegetation and soils at the spring on a scale of 1–4, where 1 = undisturbed, 2 = slightly disturbed, 3 = moderately disturbed, and 4 = highly disturbed. Types of natural disturbances can include flooding, drying, fire, wildlife impacts, windthrow of trees and shrubs, beaver activity, and insect infestations. Anthropogenic disturbances can include roads, off-highway vehicle trails, hiking trails, livestock and feral-animal impacts, removal of invasive non-native plants, flow modification, and other evidence of human use of the spring site. We take repeat photographs from the same location and perspective to show the spring and its landscape context. We note the presence of certain obligate wetland plant species (plant species that almost always occur only in wetlands), facultative wetland plant species (plant species that usually occur in wetlands, but also occur in other habitats), and invasive non-native crayfish and American bullfrog (Rana catesbeiana). We also record the density of invasive non-native plants using a qualitative scale (1–5 plants, scattered patches, evenly distributed patches, or a matrix). We complete the site condition module during each springs monitoring visit.

Water Quantity

We measure the persistence of surface water, amount of spring discharge, and wetted extent (area that contained water). To estimate persistence, we analyze the variance of temperature measurements taken by two logging thermometers placed at or near the orifice (spring opening). Because water mediates variation in diurnal temperatures, data from a submerged sensor will show less daily variation than data from an exposed, open-air sensor; this tells us when the spring was wet or dry. Surface discharge is measured with a timed sample of water volume. Wetted extent is a systematic measurement of the physical length (up to 100 m), width, and depth of surface water. It is assessed using a technique for either standing water (e.g., limnocrene and helocrene springs) or flowing water (e.g., rheocrene springs). We complete discharge and wetted extent measurements during each visit when possible. Water persistence measurements are continuous throughout the year.

Water Quality

We measure core water quality and water chemistry parameters. Core water quality parameters include water temperature, pH, specific conductivity (a measure of dissolved compounds and contaminants), dissolved oxygen (how much oxygen is present in the water), and total dissolved solids (an indicator of potentially undesirable compounds). Discrete measurements of these parameters are collected with a multiparameter meter. If the meter fails calibration checks, we do not present data. Water chemistry is assessed by collecting surface water samples and estimating the concentration of major ions with a photometer in the field. These parameters are collected at one or more sampling locations within a spring. Data are presented only for the primary sampling location within each spring. Each perennial spring is somewhat unique, and New Mexico has not adopted water quality standards that would apply across the diversity of springs described here. Ongoing, long-term data collection at each spring will improve our understanding of the natural range in water quality and water chemistry parameters for a given site. We complete the water quality module during each visit when possible.

eDNA Inventory of Rare and Invasive Species and Pathogens

We inventory rare species, invasive species, and pathogens in perennial springs using environmental DNA (eDNA) techniques. In 2023 and 2024, four or more water samples (250 mL/sample) were collected and filtered (0.45 µm) from each spring and then preserved in ethanol prior to DNA extraction and analysis by the Goldberg Lab at Washington State University. Our target organisms for the inventory include American bullfrog (Rana catesbeiana), chytrid fungus (Batrachochytrium dendrobatidis), ranavirus (Iridoviridae), red spotted toad (Bufo punctatus), Rio Grande leopard frog (Rana berlandieri), and Woodhouse’s toad (Anaxyrus woodhousii).

Results

Iron Pipe Seep

Highlights: The spring contained water when we visited but was dry for significant periods in WY2024. Discharge was much higher than average, and the wetted area was similar to prior years. We found rabbitsfoot grass, an invasive plant not previously observed at the spring.

Iron Pipe Seep (Figures 4 and 5) is a rheocrene spring (a spring that emerges into one or more stream channels) located in the upper elevations of an east-facing ridge overlooking West Slaughter Canyon below a rock outcrop. Cool, clear water trickles from a historical 1-inch-diameter pipe, protruding a few inches out from the hillside. It forms an intermittent channel that has measured up to 7.3 m (24.0 ft) long. Grasses, shrubs, and junipers dot the area immediately surrounding the spring. The WY2024 visit occurred on 16 March 2024, and the spring contained water.

Figure 4. A close-up image of a pipe emerging from the ground, surrounded by yellow and green grasses. Algae hangs from the pipe and in the water.
Figure 4. The primary emergence of Iron Pipe Seep at Carlsbad Caverns National Park, March 2024.

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Figure 5. A small wet area on a hillside amidst scattered rocks, grasses, shrubs, and trees.
Figure 5. Overview of Iron Pipe Seep and the surrounding landscape at Carlsbad Caverns National Park, March 2024. The primary emergence is among the grasses to the left of the green shrubs.

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Site Condition

In WY2024, we rated Iron Pipe Spring moderately disturbed by flow modification because the primary source of flow is an iron pipe protruding from the bank. Tracks, game trails, and scat indicate wildlife is using the spring. No other natural or human-caused disturbances were observed at Iron Pipe Seep in WY2024.

As in past years, we did not observe invasive non-native crayfish or American bullfrog (Rana catesbeiana) at Iron Pipe Seep in WY2024. We observed one invasive non-native plant species at the spring: scattered patches of annual rabbitsfoot grass (Polypogon monspeliensis, not previously observed).

We observed two obligate/facultative wetland plant species: a member of the rush family (Juncacaeae, observed in 2018–2023) and a sedge (Carex sp., observed in 2018–2022).

eDNA Inventory of Rare and Invasive Species and Pathogens

In WY2024, four water samples were collected from Iron Pipe Seep. None of our target organisms were detected. In WY2023, three water samples were collected, and red spotted toad (Bufo punctatus) was detected in one of the samples.

Water Quantity

Sensors are deployed and data are downloaded during our annual visit; the dates of these visits are indicated by black diamonds in the persistence graph (Figure 6). The temperature sensor indicated that Iron Pipe Seep was wetted (contained water) for 57 of 168 days (33.9%) measured in WY2024 up to the visit. In prior water years, the spring was wetted 6.1–72.9% of the days measured across entire years.

Figure 6. Area chart showing the spring was intermittently wetted with longer dry periods during the summer months. Water years 2021 to 2023 experienced increased periods of water persistence in the winter and spring months. The first half of water year 2024 was intermittently dry.
Figure 6. Water persistence through 16 March 2024 in Iron Pipe Seep, Carlsbad Caverns National Park. White areas indicate dates before sensors were first deployed or after the WY2024 visit. Black diamonds indicate sensor deployment dates.

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In WY2024 the estimated volumetric discharge was 3.0 ± 0.1 L/min (0.8 ± 0.03 gal/min), representing a substantial increase compared to a prior range of means between 0.0 and 0.3 L/min (0.0–0.1 gal/min) from 2018 to 2023 (Table 1). Wetted extent was evaluated using a method for flowing water. The total springbrook length was 6.4 m (21.0 ft), which falls within the historical range of 0.5–7.3 m (1.6–24.0 ft). In WY2024, width and depth along the springbrook averaged 21.4 cm (8.4 in) and 0.3 cm (0.1 in), respectively. Width in WY2024 was within the range of prior values, while depth was slightly lower than previously recorded (Table 2).

Table 1. Discharge data (L/min; mean ± SD) for Iron Pipe Seep in water year (WY) 2024 and a range of means from prior years.
Sampling Location WY2024 Mean
(Range of Prior Means)		 Prior Years Measured
(# of Visits with Measurements)
001 3.0 ± 0.1 (0.0–0.3) 2018–2023 (6)

Table 2. Length and average (± SD) width and depth of Iron Pipe Seep (measured within the first 100 m of springbrook length) in water year (WY) 2024 and ranges of length values and width and depth means from prior years.
Measurement WY2024 Value
(Range of Prior Values/Means)		 Prior Years Measured
(# of Visits with Measurements)
Width (cm) 21.4 ± 32.8 (13.6–31.2) 2018–2023 (6)
Depth (cm) 0.3 ± 0.4 (0.4–0.7) 2018–2023 (6)
Length (m) 6.4 (0.5–7.3) 2018–2023 (6)
Water Quality

Core water quality (Table 3) and water chemistry (Table 4) data were collected at the primary sampling location in WY2024, directly from the iron pipe. Dissolved oxygen, pH, and water temperature were within the ranges of previously recorded values (2018–2023), while specific conductivity and total dissolved solids were slightly lower. Levels of alkalinity, calcium, magnesium, potassium, and sulphate were within prior value ranges (2018–2023), while chloride was lower.

Table 3. Core water quality data for Iron Pipe Seep in water year (WY) 2024 and a range of values from prior years.
Sampling Location Parameter WY2024 Value
(Range of Prior Values)		 Prior Years Measured
(# of Measurements)
001 Dissolved oxygen (mg/L) 2.51 (1.71–7.35) 2018–2023 (7)
001 pH 7.04 (6.86–7.05) 2018–2023 (5)
001 Specific conductivity (µS/cm) 661 (662–764) 2018–2023 (6)
001 Temperature (°C) 13.6 (13.2–19.6) 2018–2023 (9)
001 Total dissolved solids (mg/L) 429.5 (430.0–497.0) 2018–2023 (6)

Table 4. Water chemistry data (mg/L) for Iron Pipe Seep in water year (WY) 2024 and a range of values from prior years.
Sampling Location Parameter WY2024 Value
(Range of Prior Values)		 Prior Years Measured
(# of Measurements)
001 Alkalinity (CaCO3) 295 (285–390) 2018–2023 (6)
001 Calcium (Ca) 52 (18–56) 2018–2023 (6)
001 Chloride (Cl) 2 (5–61) 2018–2023 (6)
001 Magnesium (Mg) 70 (48–90) 2018–2023 (6)
001 Potassium (K) 0.8 (0.1–1.6) 2018–2023 (6)
001 Sulphate (SO4) 8 (3–9) 2018–2023 (6)

Oak Spring

Highlights: The spring contained water when we visited and was wet over 80% of the days measured in WY2024. However, the springbrook was much shorter than in prior years, and the plunge pool was completely dry.

Oak Spring (Figures 7 and 8) is a rheocrene spring (a spring that emerges into one or more stream channels) originating from several distinct orifices in an east-facing drainage lined with oak and juniper, about 1 km northwest of the Carlsbad Caverns Visitor Center. The primary orifice seeps cool, clear water from a bedrock seam inside the drainage, where a man-made rock dam confines the flow into a crescent-shaped pool. Additional seeps produce flow along the bedrock walls in the drainage and contribute to a plunge pool further down the channel. The WY2024 visit occurred on 01 March 2024, and the spring contained water.

Figure 7. A person crouches next to a crescent-shaped pool of shallow water in a depression in bedrock and points to its surface. There is leaf litter in the water and on surrounding rocks.
Figure 7. The primary emergence of Oak Spring at Carlsbad Caverns National Park, March 2024.

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Figure 8. A u-shaped pool in a bedrock canyon bottom that is lined with trees and shrubs.
Figure 8. Overview of Oak Spring and the surrounding landscape at Carlsbad Caverns National Park, March 2024.

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Site Condition

In WY2024, we rated Oak Spring slightly disturbed by drying based on the complete drying of a plunge pool that previously held water and the presence of upland species in the riparian area (rated undisturbed to moderately disturbed in the past; Figure 9). We rated the spring slightly disturbed by fire with charred stumps in the vicinity (rated undisturbed to slightly disturbed in the past); and moderately disturbed by flow modification related to pipes, rock walls, and dams (rated undisturbed to highly disturbed in the past). No other natural or human-caused disturbances were observed at Oak Spring in WY2024.

Figure 9. A person points to a depression with green vegetation in a canyon bottom dotted with rocks and lined with yellow grasses and leafless trees.
Figure 9. Example of disturbance (drying of the plunge pool) at Oak Spring in WY2024.

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As in past years, we did not observe invasive non-native crayfish or American bullfrog (Rana catesbeiana) at Oak Spring in WY2024. We observed two species of invasive non-native plants at the spring: evenly distributed patches of Bermudagrass (Cynodon dactylon, evenly distributed patches to a matrix observed in 2017–2023) and scattered patches of horehound (Marrubium vulgare, scattered patches to evenly distributed patches observed in 2017–2023).

We observed two obligate/facultative wetland plant species: maidenhair fern (Adiantum sp., a fern observed in 2018–2023) and a sedge (Carex sp., observed in 2018–2023).

eDNA Inventory of Rare and Invasive Species and Pathogens

In WY2024, five water samples were collected from Oak Spring. None of our target organisms were detected, similar to WY2023.

Water Quantity

Sensors are deployed and data are downloaded during our annual visit; the dates of these visits are indicated by black diamonds in the persistence graph (Figure 10). The temperature sensor indicated that Oak Spring was wetted (contained water) for 126 of 153 days (82.4%) measured in WY2024 up to the visit. In prior water years, the spring was wetted 69.9–100% of the days measured across entire years.

Figure 10. Area chart showing the spring was mostly wet during measured periods from water year 2018 through water year 2020. From that point to April 2023, there were sensor failure issues and only a few short periods of data were available in spring 2021 and spring 2022 that show the spring was wet all the time. The second half of water year 2023 and all of water year 2024 were largely wet with intermittent dry periods.
Figure 10. Water persistence through 01 March 2024 in Oak Spring, Carlsbad Caverns National Park. White areas indicate dates before sensors were first deployed or after the WY2024 visit. Black diamonds indicate sensor deployment dates.

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Discharge was not measured in WY2024 because of a lack of measurable surface flow. Discharge estimates have ranged from 0.4–0.6 L/min (0.1–0.2 gal/min) in past years (Table 5). Wetted extent was evaluated using a method for flowing water. The total springbrook length was 2.4 m (7.9 ft), which was notably shorter than the previously recorded range of 10.9–43.6 m (35.8–143.0 ft). Average springbrook width was 127.2 cm (50.1 in), and depth was 1.8 cm (0.7 in). Width was greater than in prior years, while depth remained within the historical range (Table 6).

Table 5. Discharge data (L/min; mean ± SD) for Oak Spring in water year (WY) 2024 and a range of means from prior years. c.n.s. = could not sample.
Sampling Location WY2024 Mean
(Range of Prior Means)		 Prior Years Measured
(# of Visits with Measurements)
004 c.n.s. (0.4–0.6) 2018–2019 (2)

Table 6. Length and average (± SD) width and depth of Oak Spring (measured within the first 100 m of springbrook length) in water year (WY) 2024 and ranges of length values and width and depth means from prior years.
Measurement WY2024 Value
(Range of Prior Values/Means)		 Prior Years Measured
(# of Visits with Measurements)
Width (cm) 127.2 ± 52.3 (26.4–64.5) 2018–2023 (6)
Depth (cm) 1.8 ± 2.4 (0.4–2.1) 2018–2023 (6)
Length (m) 2.4 (10.9–43.6) 2018–2023 (6)
Water Quality

Core water quality (Table 7) and water chemistry (Table 8) data were collected at the primary sampling location in WY2024. Specific conductivity, pH, and total dissolved solids were within the ranges of prior measurements, while dissolved oxygen and water temperature were lower than in prior years. The values for calcium, chloride, magnesium, potassium, and sulphate were within the ranges previously recorded, and the alkalinity level was slightly lower.

Table 7. Core water quality data for Oak Spring in water year (WY) 2024 and a range of values from prior years.
Sampling Location Parameter WY2024 Value
(Range of Prior Values)		 Prior Years Measured
(# of Measurements)
001 Dissolved oxygen (mg/L) 2.75 (4.64–8.02) 2019–2023 (4)
001 pH 7.80 (7.75–8.12) 2018–2023 (4)
001 Specific conductivity (µS/cm) 558.0 (525.0–594.8) 2018–2023 (5)
001 Temperature (°C) 8.4 (8.7–15.8) 2018–2023 (8)
001 Total dissolved solids (mg/L) 362.7 (342.0–389.0) 2018–2023 (6)

Table 8. Water chemistry data (mg/L) for Oak Spring in water year (WY) 2024 and a range of values from prior years.
Sampling Location Parameter WY2024 Value
(Range of Prior Values)		 Prior Years Measured
(# of Measurements)
001 Alkalinity (CaCO3) 240 (250–270) 2018–2023 (6)
001 Calcium (Ca) 50 (46–64) 2018–2023 (6)
001 Chloride (Cl) 5 (2–31) 2018–2023 (6)
001 Magnesium (Mg) 40 (0–65) 2018–2023 (6)
001 Potassium (K) 1.3 (0.5–1.7) 2018–2023 (6)
001 Sulphate (SO4) 0 (0–21) 2018–2023 (6)

Slaughter Pot Hole

Highlights: The spring contained water when we visited, but we have no persistence data for the year. The wetted area was similar to prior years. We observed one new invasive plant species: Lehmann lovegrass.

Slaughter Pot Hole (Figures 11 and 12) is a tinaja (a small pool in a rock basin or impoundment in bedrock) located in the upper elevations of Slaughter Canyon. The north, east, and west sides of the pool have sloping, slickrock walls, and the southwest side has a gentler slope that opens to a dry cobblestone wash where the Slaughter Canyon Trail passes through. The WY2024 visit occurred on 04 March 2024, and the spring contained water.

Figure 11. A brown-tinged pool in a bedrock basin with a crouched person at the edge of the pool pointing down at the water.
Figure 11. Slaughter Pot Hole at Carlsbad Caverns National Park, March 2024.

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Figure 12. A desert canyon landscape with a brown-tinged pool in a bedrock basin in the foreground. There are hillsides dotted with rocks and shrubs in the background.
Figure 12. Overview of Slaughter Pot Hole and the surrounding landscape at Carlsbad Caverns National Park, March 2024.

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Site Condition

No natural or human-caused disturbances were observed at Slaughter Pot Hole in WY2024.

As in past years, we did not observe invasive non-native crayfish or American bullfrog (Rana catesbeiana) at Slaughter Pot Hole in WY2024. We observed two species of invasive non-native plants at the spring: 1–5 Lehmann lovegrass plants (Eragrostis lehmanniana, not previously observed) and 1–5 common mullein plants (Verbascum thapsus, 1–5 plants observed in 2017–2018). We did not observe any obligate/facultative wetland plants.

eDNA Inventory of Rare and Invasive Species and Pathogens

In WY2024, four water samples were collected from Slaughter Pot Hole. None of our target organisms were detected, similar to WY2023.

Water Quantity

Sensors are deployed and data are downloaded during our annual visit; the dates of these visits are indicated by black diamonds in the persistence graph (Figure 13). Temperature sensor data are missing for the primary sampling location at Slaughter Pot Hole because the sensor was moved to a new sampling location, so there is no estimate of persistence for WY2024. In prior water years, the spring was wetted 46.2–100% of the days measured across entire years.

Figure 13. Area chart showing missing data from March 2017 to April 2018, July 2018 to April 2019, and April 2021 to April 2024. Outside those times, the tinaja was wet except January to April 2021.
Figure 13. Water persistence through 04 March 2024 in Slaughter Pot Hole, Carlsbad Caverns National Park. White areas indicate dates before sensors were first deployed or after the WY2024 visit. Black diamonds indicate sensor deployment dates.

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As in past years, there was no measurable discharge from the tinaja. Slaughter Pot Hole was evaluated using a method for standing water. Width averaged 195.5 cm (77.0 in), length averaged 3.04 m (9.97 ft), and depth averaged 68.3 cm (26.9 in), all of which were within the ranges of prior measurements over the last seven years (Table 9).

Table 9. Average (± SD) width, depth, and length of Slaughter Pot Hole in water year (WY) 2024 and a range of means from prior years.
Measurement WY2024 Mean
(Range of Prior Means)		 Prior Years Measured
(# of Visits with Measurements)
Width (cm) 195.5 ± 44.0 (63.2–404.3) 2017–2023 (7)
Depth (cm) 68.3 ± 55.6 (24.3–109.5) 2017–2023 (7)
Length (m) 3.04 ± 1.01 (0.96–4.46) 2017–2023 (7)
Water Quality

Core water quality (Table 10) and water chemistry (Table 11) data were collected at the primary sampling location in WY2024. All water quality and chemistry parameters were within the ranges of prior measurements.

Table 10. Core water quality data for Slaughter Pot Hole in water year (WY) 2024 and a range of values from prior years.
Sampling Location Parameter WY2024 Value
(Range of Prior Values)		 Prior Years Measured
(# of Measurements)
001 Dissolved oxygen (mg/L) 10.82 (0.56–17.40) 2018–2023 (6)
001 pH 8.92 (8.91–9.51) 2018–2023 (5)
001 Specific conductivity (µS/cm) 335.4 (182.4–644.0) 2018–2023 (6)
001 Temperature (°C) 12.1 (10.6–17.0) 2018–2023 (8)
001 Total dissolved solids (mg/L) 217.9 (118.0–419.0) 2018–2023 (6)

Table 11. Water chemistry data (mg/L) for Slaughter Pot Hole in water year (WY) 2024 and a range of values from prior years. b.d.l. = below detection limit.
Sampling Location Parameter WY2024 Value
(Range of Prior Values)		 Prior Years Measured
(# of Measurements)
001 Alkalinity (CaCO3) 150 (90–350) 2017–2023 (7)
001 Calcium (Ca) 38 (22–54) 2017–2023 (7)
001 Chloride (Cl) b.d.l. (b.d.l.–12) 2017–2023 (7)
001 Magnesium (Mg) 18 (b.d.l.–58) 2017–2023 (7)
001 Potassium (K) 7.2 (2.3–36.0) 2017–2023 (7)
001 Sulphate (SO4) 0 (b.d.l.–6) 2017–2023 (7)

Upper East Grammer Spring

Highlights: The spring contained water when we visited. It was mostly wet in the fall and dry in the winter and early spring of WY2024. The wetted area was similar to prior years. We observed one new invasive plant species: Lehmann lovegrass.

Upper East Grammer Spring (Figures 14 and 15) is a rheocrene spring (a spring that emerges into one or more stream channels) located in a south-facing side drainage of Walnut Canyon that has ranged from 16.5 to 43.5 m (54.1–142.7 ft) in length in recent years. The spring is a slow seep that emerges from a rounded limestone bedrock seam inside the rocky drainage. It forms shallow pools in shaded areas and flows subsurface intermittently. The WY2024 visit occurred on 01 March 2024, and the spring contained water.

Figure 14. A person points to a wet patch under tree branches inside a desert drainage lined with bedrock.
Figure 14. The primary emergence at Upper East Grammer Spring at Carlsbad Caverns National Park, March 2024.

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Figure 15. A bedrock-lined drainage dotted with shrubs and grasses.
Figure 15. Overview of Upper East Grammer Spring and the surrounding landscape at Carlsbad Caverns National Park, March 2024.

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Site Condition

In WY2024, we rated Upper East Grammer Spring slightly disturbed by feral animals because of non-native Barbary sheep (Ammotragus lervia) scat and trails (rated undisturbed to moderately disturbed in the past). Tracks, scat, and game trails indicate wildlife are using the spring. No other natural or human-caused disturbances were observed at Upper East Grammer Spring in WY2024.

As in past years, we did not observe invasive non-native crayfish or American bullfrog (Rana catesbeiana) at Upper East Grammer Spring in WY2024. We observed one invasive non-native plant species at the spring: scattered patches of Lehmann lovegrass (Eragrostis lehmanniana, not previously observed).

We found three obligate/facultative wetland plant species: bluestem (Andropogon sp., a grass observed in 2018–2023); maidenhair fern (Adiantum sp., a fern observed in 2017–2023); and a sedge (Carex sp., observed in 2018–2023).

eDNA Inventory of Rare and Invasive Species and Pathogens

In WY2024, four water samples were collected from Upper East Grammer Spring. None of our target organisms were detected, similar to WY2023.

Water Quantity

Sensors are deployed and data are downloaded during our annual visit; the dates of these visits are indicated by black diamonds in the persistence graph (Figure 16). The temperature sensor indicated that Upper East Grammer Spring was wetted (contained water) for 71 of 153 days (46.4%) measured in WY2024 before the sampling visit. In prior water years, the spring was wetted 97.5–100% of the days measured across entire years.

Figure 16. Area chart showing the spring was wetted April 2018 to April 2022 and April 2023 to October 2023 except very short periods of intermittent dryness in spring 2019 and winter/spring 2024 when the spring was dry more often than wet. Sensors were first deployed in March 2018 and data are missing April 2022 to April 2023.
Figure 16. Water persistence through 01 March 2024 in Upper East Grammer Spring, Carlsbad Caverns National Park. White areas indicate dates before sensors were first deployed or after the WY2024 visit. Black diamonds indicate sensor deployment dates.

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Discharge was not measured in WY2024 at the primary sampling location because there was no measurable flow. Discharge ranged from 0.6 to 0.9 L/min (0.1–0.2 gal/min) in 2018–2019 (Table 12). Wetted extent was evaluated using a method for flowing water. Overall, the wetted extent at Upper East Grammer Spring was comparable with prior years. The total springbrook length was 19.3 m (63.3 ft), which was within the past range of 16.5–43.5 m (54.1–142.7 ft), but on the lower end. Average width of the springbrook was 58.7 cm (23.1 in), and depth was 0.6 cm (0.2 in), both falling within the historical ranges (Table 13).

Table 12. Discharge data (L/min; mean ± SD) for Upper East Grammer Spring in water year (WY) 2024 and a range of means from prior years. c.n.s. = could not sample.
Sampling Location WY2024 Mean
(Range of Prior Means)		 Prior Years Measured
(# of Visits with Measurements)
002 c.n.s. (0.6–0.9) 2018–2019 (2)

Table 13. Length and average (± SD) width and depth of Upper East Grammer Spring (measured within the first 100 m of springbrook length) in water year (WY) 2024 and ranges of length values and width and depth means from prior years.
Measurement WY2024 Value
(Range of Prior Values/Means)		 Prior Years Measured
(# of Visits with Measurements)
Width (cm) 58.7 ± 42.4 (47.9–129.7) 2018–2023 (6)
Depth (cm) 0.6 ± 0.3 (0.3–3.0) 2018–2023 (6)
Length (m) 19.3 (16.5–43.5) 2018–2023 (6)
Water Quality

In WY2024, core water quality (Table 14) and water chemistry (Table 15) data were collected at the primary sampling location in the largest pool, 6 m downstream from the orifice. Values for dissolved oxygen, pH, and water temperature were within the ranges of prior measurements, while specific conductivity and total dissolved solids were higher. Levels of alkalinity, calcium, chloride, and potassium levels were within the ranges of measurements in prior years, while sulphate was lower, and magnesium was higher.

Table 14. Core water quality data for Upper East Grammer Spring in water year (WY) 2024 and a range of values from prior years.
Sampling Location Parameter WY2024 Value
(Range of Prior Values)		 Prior Years Measured
(# of Measurements)
001 Dissolved oxygen (mg/L) 7.14 (6.39–11.36) 2018–2023 (6)
001 pH 7.83 (7.46–8.34) 2018–2023 (4)
001 Specific conductivity (µS/cm) 635 (555–601) 2018–2023 (6)
001 Temperature (°C) 15.0 (9.0–15.7) 2018–2023 (8)
001 Total dissolved solids (mg/L) 413.1 (361.0–390.6) 2018–2023 (6)

Table 15. Water chemistry data (mg/L) for Upper East Grammer Spring in water year (WY) 2024 and a range of values from prior years. b.d.l. = below detection limit.
Sampling Location Parameter WY2024 Value
(Range of Prior Values)		 Prior Years Measured
(# of Measurements)
001 Alkalinity (CaCO3) 290 (240–300) 2018–2023 (6)
001 Calcium (Ca) 60 (16–72) 2018–2023 (6)
001 Chloride (Cl) 3 (b.d.l.–130) 2018–2023 (6)
001 Magnesium (Mg) 60 (b.d.l.–50) 2018–2023 (6)
001 Potassium (K) 1.3 (b.d.l.–1.9) 2018–2023 (6)
001 Sulphate (SO4) 0 (10–53) 2018–2023 (6)

Upper Lechuguilla Spring

Highlights: The spring was wet every day up to our visit in WY2024. Similar to prior years, the spring was wet in fall and winter and relatively dry in spring and summer. Barbary sheep use the spring site.

Upper Lechuguilla Spring (Figures 17 and 18) is a rheocrene spring (a spring that emerges into one or more stream channels) in an east-facing stretch of West Lechuguilla Canyon that trickles out from under rocks to form a shallow, intermittently wetted springbrook. The springbrook has ranged from 3.2 to 50.5 m (10.5–165.7 ft) in length. The WY2024 visit occurred on 02 March 2024, and the spring contained water.

Figure 17. A person points to a shallow pool of water with a green surface that emerges from under rocks in a drainage dotted with rocks, dried grasses, and shrubs.
Figure 17. The primary emergence of Upper Lechuguilla Spring at Carlsbad Caverns National Park, March 2024.

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Figure 18. A hillslope covered in small trees, shrubs, and dried grasses. Rocks dot the slopes.
Figure 18. Overview of Upper Lechuguilla Spring and the surrounding landscape at Carlsbad Caverns National Park, March 2024. The spring is in the center of the photo.

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Site Condition

In WY2024, we rated Upper Lechuguilla Spring slightly disturbed by feral animals based on non-native Barbary sheep (Ammotragus lervia) tracks at the site (rated undisturbed to moderately disturbed in the past); slightly disturbed by drying because two previously wetted spring orifices were complete dry (rated undisturbed to highly disturbed in the past; Figure 19); and slightly disturbed by fire with charred stumps in the vicinity (rated undisturbed to slightly disturbed in the past). Tracks and scat indicate wildlife are using the spring. No other natural or human-caused disturbances were observed at Upper Lechuguilla Spring in WY2024.

Figure 19. A person points to the ground in a rocky drainage dotted with shrubs and dried grasses.
Figure 19. This previously wetted spring orifice is dry at Upper Lechuguilla Spring in WY2024.

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As in past years, we did not observe invasive non-native crayfish or American bullfrog (Rana catesbeiana) at Upper Lechuguilla Spring in WY2024, nor did we observe any invasive non-native plants at the spring.

We observed three obligate/facultative wetland plant species: a member of the rush family (Juncaceae, observed in 2018–2023); a sedge (Carex sp., observed in 2017–2023); and spikerush (Eleocharis sp., a sedge observed in 2018–2023).

eDNA Inventory of Rare and Invasive Species and Pathogens

In WY2024, five water samples were collected from Upper Lechuguilla Spring. None of our target organisms were detected, similar to WY2023.

Water Quantity

Sensors are deployed and data are downloaded during our annual visit; the dates of these visits are indicated by black diamonds in the persistence graph (Figure 20). The temperature sensor indicated that Upper Lechuguilla Spring was wetted (contained water) for all 154 days (100%) measured in WY2024 up to the visit. In prior water years, the spring was wetted 41.6–54.2% of the days measured across entire years.

Figure 20. Area chart showing alternating periods of wet and dry throughout the year from April 2018 to April 2024. Generally, the spring shows a pattern of being wet in the fall and winter and dry in the summer months.
Figure 20. Water persistence through 02 March 2024 in Upper Lechuguilla Spring, Carlsbad Caverns National Park. White areas indicate dates before sensors were first deployed or after the WY2024 visit. Black diamonds indicate sensor deployment dates.

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Discharge was not measured in WY2024 at the primary sampling location because there was no measurable surface flow. Discharge estimates have ranged from 0.1 to 1.7 L/min (0.04–0.7 gal/min) in past years (Table 16). Wetted extent was evaluated using a method for flowing water. Overall, the wetted extent at Upper Lechuguilla Spring was comparable with prior years. The total springbrook length was 3.4 m (11.2 ft), which was within but on the lower end of the previously recorded range of 3.2–50.5 m (10.5–165.7 ft). The average springbrook width was 54.1 cm (21.3 in), and depth was 1.7 cm (0.7 in); both were within the historical ranges (Table 17).

Table 16. Discharge data (L/min; mean ± SD) for Upper Lechuguilla Spring in water year (WY) 2024 and a range of means from prior years. c.n.s. = could not sample.
Sampling Location WY2024 Mean
(Range of Prior Means)		 Prior Years Measured
(# of Visits with Measurements)
004 c.n.s. (0.1–1.7) 2020–2023 (2)

Table 17. Length and average (± SD) width and depth of Upper Lechuguilla Spring (measured within the first 100 m of springbrook length) in water year (WY) 2024 and ranges of length values and width and depth means from prior years.
Measurement WY2024 Value
(Range of Prior Values/Means)		 Prior Years Measured
(# of Visits with Measurements)
Width (cm) 54.1 ± 30.4 (16.9–41.4) 2018–2023 (6)
Depth (cm) 1.7 ± 1.1 (0.1–1.8) 2018–2023 (6)
Length (m) 3.4 (3.2–50.5) 2018–2023 (6)
Water Quality

Core water quality (Table 18) and water chemistry (Table 19) data were collected at the primary sampling location in the largest pool in WY2024. Dissolved oxygen levels were unstable even after waiting five minutes to read the value. As a result, the dissolved oxygen result may be inaccurate. Similar to last year, a syringe was used to collect the sample for water chemistry, which may affect our results. Compared to previous measurements, dissolved oxygen, pH, and specific conductivity levels were higher, while water temperature and total dissolved solids were within the ranges of prior values. The values for chloride, magnesium, and sulphate were within the ranges of prior values, while alkalinity and potassium were higher and calcium was lower.

Table 18. Core water quality data for Upper Lechuguilla Spring in water year (WY) 2024 and a range of values from prior years.
Sampling Location Parameter WY2024 Value
(Range of Prior Values)		 Prior Years Measured
(# of Measurements)
005 Dissolved oxygen (mg/L) 20.50 A (10.40–15.54) 2022–2023 (2)
005 pH 8.15 (7.71–7.83) 2022–2023 (2)
005 Specific conductivity (µS/cm) 745 (696–732) 2022–2023 (2)
005 Temperature (°C) 11.1 (5.8–16.0) 2021–2023 (3)
005 Total dissolved solids (mg/L) 484.6 (452.0–490.0) 2021–2023 (3)

A In WY2024, dissolved oxygen levels were unstable even after waiting five minutes to read the result. As a result, the dissolved oxygen result may be inaccurate.

Table 19. Water chemistry data (mg/L) for Upper Lechuguilla Spring in water year (WY) 2024 and a range of values from prior years. A syringe was used to collect the sample in WY2024, which may affect our results. b.d.l. = below detection limit.
Sampling Location Parameter WY2024 Value
(Range of Prior Values)		 Prior Years Measured
(# of Measurements)
005 Alkalinity (CaCO3) 370 (275–340) 2021–2023 (3)
005 Calcium (Ca) 56 (60–160) 2021–2023 (3)
005 Chloride (Cl) 0 (b.d.l.–11) 2021–2023 (3)
005 Magnesium (Mg) 60 (15–60) 2021–2023 (3)
005 Potassium (K) 1.4 (b.d.l.–0.2) 2021–2023 (3)
005 Sulphate (SO4) 45 (31–56) 2021–2023 (3)

Upper Lowe Ranch Spring

Highlights: The spring has been wet year round since July of 2022, though one orifice was completely dry when we visited. The wetted area was on the lower end of average. We observed invasive Lehmann lovegrass for the first time.

Upper Lowe Ranch Spring (Figures 21 and 22) is a rheocrene spring (a spring that emerges into one or more stream channels) inside a north-facing drainage east of Rattlesnake Canyon. Multiple seeps along the base of a limestone shelf form shallow pools and saturate the soil in the immediate area. The springbrook has ranged from 2.5 m (8.2 ft) to over 100 m (328 ft) in length. The WY2024 visit occurred on 02 March 2024, and the spring contained water.

Figure 21. A person points to a shallow pool of water at the base of a rock shelf, surrounded by dried vegetation and a few green shrubs and patches of grass.
Figure 21. The primary emergence at Upper Lowe Ranch Spring at Carlsbad Caverns National Park, March 2024.

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Figure 22. A canyon bottom in a desert shrubland landscape with a few leafless trees, green shrubs, and dried vegetation.
Figure 22. Overview of Upper Lowe Ranch Spring at Carlsbad Caverns National Park, March 2024. The primary emergence is beneath the rock ledge on the left side.

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Site Condition

In WY2024, we rated Upper Lowe Ranch Spring slightly disturbed by recent flooding, with wrack on trees and shrubs (rated undisturbed to slightly disturbed in the past); slightly disturbed by drying because at least one previously wetted orifice was completely dry (rated undisturbed to highly disturbed in the past; Figure 23); slightly disturbed by fire because of a few charred stumps in the vicinity (rated undisturbed to moderately disturbed in the past); and slightly disturbed by wildlife based on abundant wildlife tracks and large ungulate bones within the springbrook (rated slightly to moderately disturbed in the past). No other natural or human-caused disturbances were observed at Upper Lowe Ranch Spring in WY2024.

Figure 23. One image is of a person pointing to the ground at the base of a rock ledge. The ground is covered in dried vegetation. There are green shrubs in the background. A second image is of a pile of bones resting on leaf litter on the ground beneath branches. There are rocks and tree trunks in the background.
Figure 23. Examples of disturbance at Upper Lowe Ranch Spring in WY2024. Left to right: drying of orifice A; ungulate remains indicate wildlife is present (predation).

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As in past years, we did not observe invasive non-native crayfish or American bullfrog (Rana catesbeiana) at Upper Lowe Ranch Spring in WY2024. We observed five species of invasive non-native plants at the spring: scattered patches of Lehmann lovegrass (Eragrostis lehmanniana, not previously observed); scattered patches of redstem stork’s bill (Erodium cicutarium, scattered patches observed in 2020); scattered patches of horehound (Marrubium vulgare, scattered patches observed in 2018–2023); scattered patches of Johnsongrass (Sorghum halepense, scattered patches observed in 2018–2023); and evenly distributed patches of common mullein (Verbascum thapsus, 1–5 plants to scattered patches observed in 2018–2023).

We observed two obligate/facultative wetland plant species: a member of the rush family (Juncaceae, observed in 2019–2023) and a sedge (Carex sp., observed in 2023).

eDNA Inventory of Rare and Invasive Species and Pathogens

In WY2024, four water samples were collected from Upper Lowe Ranch Spring. None of our target organisms were detected, similar to WY2023.

Water Quantity

Sensors are deployed and data are downloaded during our annual visit; the dates of these visits are indicated by black diamonds in the persistence graph (Figure 24). The temperature sensor indicated that Upper Lowe Ranch Spring was wetted (contained water) for all 154 days (100%) measured in WY2024 up to the visit. In prior water years, the spring was wetted 29.9–100% of the days measured across entire years.

Figure 24. Area chart showing the spring had alternating periods of wet and dry, except in water year 2024 when it was wet the entire water year. Spring and summer 2018, winter 2019, 2020, and 2023 up through the site visit in 2024 were wet. Spring and summer 2019 and 2020 were mostly dry and there were extensive dry periods in winter and spring 2021 and 2022.
Figure 24. Water persistence through 02 March 2024 in Upper Lowe Ranch Spring, Carlsbad Caverns National Park. White areas indicate dates before sensors were first deployed or after the WY2024 visit. Black diamonds indicate sensor deployment dates.

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Discharge was not measured in WY2024 at the primary sampling location because there was no measurable surface flow. Discharge was estimated at 5.1 L/min (1.3 gal/min) in WY2020 (Table 20). Wetted extent was evaluated using a method for flowing water. The total springbrook length was 2.6 m (8.5 ft), which was near the lower end of the previously recorded range of a measured 2.5 m (8.2 ft) to an estimated 100–200 m (328–656 ft). The average springbrook width was 31.7 cm (12.5 in), and average depth was 1.6 cm (0.6 in). Width was lower than in prior years, while depth remained within the historical range (Table 21).

Table 20. Discharge data (L/min; mean ± SD) for Upper Lowe Ranch Spring in water year (WY) 2024 and a range of means from prior years. c.n.s. = could not sample.
Sampling Location WY2024 Mean
(Range of Prior Means)		 Prior Years Measured
(# of Visits with Measurements)
003 c.n.s. (5.1) 2020 (1)

Table 21. Length and average (± SD) width and depth of Upper Lowe Ranch Spring (measured within the first 100 m of springbrook length) in water year (WY) 2024 and ranges of length values and width and depth means from prior years.
Measurement WY2024 Value
(Range of Prior Values/Means)		 Prior Years Measured
(# of Visits with Measurements)
Width (cm) 31.7 ± 24.0 (42.8–164.1) 2018–2023 (6)
Depth (cm) 1.6 ± 1.5 (0.8–2.6) 2018–2023 (6)
Length (m) 2.6 (2.5–100.0) 2018–2023 (6)
Water Quality

Core water quality (Table 22) and water chemistry (Table 23) data were collected at the primary sampling location in WY2024. A syringe was used to collect the sample for water chemistry, which may affect our results. Water temperature was within the range of prior values, while dissolved oxygen and pH levels were higher and specific conductivity and total dissolved solids levels were much lower than in prior years. The values for chloride, potassium, and sulphate were within the ranges of prior values, while alkalinity, calcium, and magnesium were lower.

Table 22. Core water quality data for Upper Lowe Ranch Spring in water year (WY) 2024 and a range of values from prior years.
Sampling Location Parameter WY2024 Value
(Range of Prior Values)		 Prior Years Measured
(# of Measurements)
001 Dissolved oxygen (mg/L) 16.36 (4.11–14.65) 2019–2023 (6)
001 pH 8.75 (7.57–8.39) 2018–2023 (7)
001 Specific conductivity (µS/cm) 387.3 (506.0–582.0) 2018–2023 (7)
001 Temperature (°C) 21.9 (10.4–22.3) 2018–2023 (10)
001 Total dissolved solids (mg/L) 251.8 (329.0–378.0) 2018–2023 (7)

Table 23. Water chemistry data (mg/L) for Upper Lowe Ranch Spring in water year (WY) 2024 and a range of values from prior years. A syringe was used to collect the sample for water chemistry, which may affect our results.
Sampling Location Parameter WY2024 Value
(Range of Prior Values)		 Prior Years Measured
(# of Measurements)
001 Alkalinity (CaCO3) 170 (225–295) 2018–2023 (6)
001 Calcium (Ca) 44 (52–64) 2018–2023 (6)
001 Chloride (Cl) 0 (0–265) 2018–2023 (6)
001 Magnesium (Mg) 29 (34–65) 2018–2023 (6)
001 Potassium (K) 0.3 (0.0–1.3) 2018–2023 (6)
001 Sulphate (SO4) 2 (0–8) 2018–2023 (6)

Past Reports

Previous annual reports can be found at the following links:

Literature Cited

Author Information

Kristina Fahey 1

Kara Raymond 2  ORCID.org logo https://orcid.org/0009-0004-7265-5919

Tani Hubbard 3  ORCID.org logo  https://orcid.org/0009-0009-8777-4773

1 National Park Service
Chihuahuan Desert Network
New Mexico State University
MSC 3ARP, 3655 Research Dr.
Genesis Building D
Las Cruces, NM 88003

2 National Park Service
Southern Arizona Office
12661 E. Broadway Blvd.
Tucson, AZ 85748

3 Northern Rockies Conservation Cooperative and National Park Service
12661 E. Broadway Blvd.
Tucson, AZ 85748

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