USGS Water-Year Summary 2025

433528092265103 NTR2-3A North Drained Site Transect 2

Sand and gravel aquifers (glaciated regions)
Pleistocene Series

LOCATION - Lat 43°35'28.37", long 92°26'51.00" referenced to North American Datum of 1983, in NW 1/4 SW 1/4 sec.31, T.102 N., R.13 W., Fillmore County, MN, Hydrologic Unit 07060002, The piezometer is located approximately 1.75 miles SW of Ostrander, MN. The piezometer is located in an agricultural field. The piezometer is located approximately 0.4 miles NE of the intersection of 160 street and Mower/Fillmore County Line Road.

GROUNDWATER RECORDS

WELL CHARACTERISTICS - Depth 5.31 ft. Upper casing diameter 1.57 in; top of first opening 2.69 ft, bottom of last opening 4.73 ft. Piezometer NTR2-3A was installed using several sections of 3.25-inch-diameter Geoprobe rods to a depth of 5.5 feet. The piezometer is constructed of a 2.04-feet-long, 1.5-inch-diameter, schedule-40 PVC, 0.010-inch slotted Hole Products Inc. well screen, flush threaded to length/s of 5.00 feet of 1.5-inch-diameter, schedule-40 PVC well casing. The piezometer casing measuring point (stickup) was 1.58 feet (1341.11 ft. NAVD88, +/- 0.05 ft.) above land surface when measured on 27 April 2016. The open interval of the piezometer is between 2.69 and 4.73 feet below land surface and the total well depth is 5.31 feet below land surface.

This piezometer is screened in glacial till/clay sediment, which is overlies bedrock.

DATUM - Land-surface datum is 1,339.53 ft above North American Vertical Datum of 1988. Measuring point: This initial MP height was cut on 2016-04-27, 2.22 ft above land-surface datum, Apr. 26, 2016 to Apr. 26, 2016; Black mark on top of PVC well casing, 1.58 ft above land-surface datum, Apr. 27, 2016 to present.

The current measuring point is a black mark on the top of the white PVC 1.5-inch diameter well casing, which was 1.58 feet above land surface on 27 April 2016. Elevation of the measuring point is 1341.11 plus-or-minus 0.05 feet above sea level, North American Vertical Datum of 1988, based on differential GPS survey on 20 August 2016.

The original/initial measuring point was a black mark on the top of the white PVC 1.5-inch diameter well casing, which was 2.22 feet above land surface on 26 April 2016. Elevation of the measuring point is 1341.75 plus-or-minus 0.05 feet above sea level, North American Vertical Datum of 1988, based on differential GPS survey on 20 August 2016.

PERIOD OF RECORD -

Water Level:

Water levels were recorded periodically from 16 June 2016 to 30 October 2018. Water levels were recorded quarter-hourly from 16 March 2017 at 17:30 CDT to 02 Nov. 2017 at 15:00 CDT to 30 October 2018 at 09:45 CDT, except during the following periods:

30 Aug. 2017 at 09:30 CDT to 02 Nov. 2017 at 14:45 CDT: due to full transducer memory; newest data did not over-write oldest data.

18 Feb. 2018 at 05:15 CST to 06 Mar. at 07:30 CST: due to water level dropping below bottom of transducer.

16 Apr. 2018 at 07:30 CDT to 02 May 2018 at 07:45 CDT: due to deleting data caused by an unknown and unexplainable shift.

13 Aug. 2018 at 17:30 CDT to 07 Sept. 2018 at 20:30 CDT: due to water level dropping below bottom of transducer.

25 Sept. 2018 at 02:00 CDT to 30 Oct. 2018 at 09:45 CDT: due to full transducer memory; newest data did not over-write oldest data.

Soil moisture and soil temperature were recorded quarter-hourly during 14 September 2016 at 16:00 CDT to 02 November 2018 at 17:30 CDT, except during the following periods:

Soil temperature at 1.3 ft. BLS (center):

16 Jun. 2017 at 13:30 CDT - 31 Oct. 2017 at 16:30 CDT: unknown datalogger failure caused no data to be recorded.

Soil temperature at 1.3 ft. BLS (near tile):

14 Sept. 2016 at 16:00 CDT - 09 Nov. 2016 at 12:00 CST: sensor was not installed at the site during this period.

09 Nov. 2016 at 12:15-13:00 CST: soil temperatures were equilibrating after ground disturbance during sensor installation.

16 Jun. 2017 at 13:30 CDT - 31 Oct. 2017 at 16:30 CDT: unknown datalogger failure caused no data to be recorded.

Soil temperature at 2.7 ft. BLS (center):

16 Jun. 2017 at 13:30 CDT - 31 Oct. 2017 at 16:30 CDT: unknown datalogger failure caused no data to be recorded.

Soil temperature at 2.7 ft. BLS (near tile):

14 Sept. 2016 at 16:00 CDT - 09 Nov. 2016 at 13:30 CST: sensor was not installed at the site during this period.

09 Nov. 2016 at 12:15-13:00 CST: soil temperatures were equilibrating after ground disturbance during sensor installation.

16 Jun. 2017 at 13:30 CDT - 31 Oct. 2017 at 16:45 CDT: unknown datalogger failure caused no data to be recorded.

Soil moisture at 1.3 ft. BLS (center):

16 Jun. 2017 at 13:30 CDT - 31 Oct. 2017 at 17:00 CDT: unknown datalogger failure caused no data to be recorded.

Soil moisture at 1.3 ft. BLS (near tile):

14 Sept. 2016 at 16:00 CDT - 09 Nov. 2016 at 12:00 CST: sensor was not installed at the site during this period.

09 Nov. 2016 at 12:15-20:45 CST: soil temperatures were equilibrating after ground disturbance during sensor installation.

16 Jun. 2017 at 13:30 CDT - 31 Oct. 2017 at 16:45 CDT: unknown datalogger failure caused no data to be recorded.

Soil moisture at 2.7 ft. BLS (center):

16 Jun. 2017 at 13:30 CDT - 31 Oct. 2017 at 16:45 CDT: unknown datalogger failure caused no data to be recorded.

Soil moisture at 2.7 ft. BLS (near tile):

14 Sept. 2016 at 16:00 CDT - 09 Nov. 2016 at 13:30 CST: sensor was not installed at the site during this period.

16 Jun. 2017 at 13:30 CDT - 31 Oct. 2017 at 16:45 CDT: unknown datalogger failure caused no data to be recorded.

GAGE - Continuous water level, water temperature, and specific conductance were measured with a new Solinst Model 3001 Levelogger LTC non-vented pressure transducer from 16 March 2017 at 17:30 CDT to 30 October 2018 at 09:45 CDT. These data were recorded quarter-hourly by the Solinst Model 3001 LTC Levelogger pressure transducer, which had an internal data logger built into it. The data logger was housed inside the 1.5-inch PVC well casing. The piezometer has a slip-on PVC cap and no pad lock. The gage was powered by an internal pressure transducer battery. A Solinst Model 3001 Barologger Edge atmospheric barometer was also installed (hanging) in this piezometer. These barometric pressure data were used to post-process/correct the non-vented pressure transducer data. Continuous soil moisture and soil temperature were measured with 4 new Decagon 5TM Soil Moisture & Temperature Sensors from 14 September 2016 at 16:00 CDT to 02 November 2018 at 17:30 CDT. A 2-sensor array is installed at 1.3 ft. BLS and 2.7 ft. BLS in the "center" of the NTR2 piezometer nest. A 2-sensor array is installed at 1.3 ft. BLS and 2.7 ft. BLS "near" the tile line, close to the NTR2-5 piezometer. The 4 soil moisture & temperature sensor cables were buried underground and wired into one data logger at the NTR2-3A piezometer. These data were recorded quarter-hourly by a Decagon Em50 digital data logger. The data logger was housed inside a 12'' x 14'' fiberglass shelter. The shelter was locked and was mounted to a green fence post. This data logger was powered by 5 AA alkaline batteries. All data were downloaded manually and no telemetry or phone line was wired into the gage.

A Solinst Model 3001 Barologger Edge atmospheric barometer was also installed in this piezometer. This was a 'primary' Barologger for the North Site. All Solinst 3001 Levelogger transducers at the North Drained Site are subtracting the values from this Barologger to convert to WL, ft. BLS. In case this "primary" Barologger goes bad, a "Secondary/backup" Barologger was installed at nearby site NTR1-3 and also recorded barometric pressure data at the North Drained Site.

The pressure transducer, data logger, and Barologger were removed from the well on 30 Oct. 2018 at 10:15 CDT. Data collection for the Impacts on Drainage Recharge study have concluded and all data logging equipment have been removed from the site.

The Decagon Em50 digital data logger and soil moisture/temperature probes were removed from the site on 02 Nov. 2018 at 17:30 CDT. Data collection for the Impacts on Drainage Recharge study have concluded and all data logging equipment have been removed from the site.

COOPERATION - This site was operated (2016-2018) by the U.S. Geological Survey as a monitoring piezometer for the Southeast Minnesota Subsurface Drainage Impacts on Groundwater Recharge study. The piezometer began to be used as part of the Southeast Minnesota Subsurface Drainage Impacts on Groundwater Recharge study during 26 Apr. 2016 to 29 Oct. 2018. The GW Drainage Recharge study is a collaborative effort between the Environment and Natural Resources Trust Fund (via Legislative-Citizen Commission on Minnesota Resources (LCCMR)) and the U.S. Geological Survey.

REMARKS - Continuous water levels are measured with a sealed (non-vented) pressure transducer. Transducer water-levels are compensated for barometric-pressure variations the record of a nearby barometric-pressure sensor located at site NTR2-3A. The water-level record is linearly corrected to calibration water levels twice per year (Spring & Fall). Calibration water levels are measured with electric or steel tapes that are themselves calibrated about every 3 years.

Water levels below land surface appear accurate to about ±0.10 feet during 16 March 2017 to 30 October 2018 based on short-term water-level variability and calibration corrections of the water level record. Sequential water-level differences are accurate to ±0.01 feet based on manufacture specifications. However, the entire water-level record contains cyclic artifacts of the barometric pressure that remain after raw water levels from the unvented pressure transducer are corrected with the barometric pressure record.  These artifacts, which are not real water level changes, are circum-daily in period and have an amplitude of about 0.02 to 0.05 feet.  Additionally, the water-level record is biased depending on where in the barometric-artifact cycle calibration corrections are made.  The direction of this bias is unknown, but the amount is less than or equal to the amplitude that of the artifact cycle.

Water elevation above North American Vertical Datum of 1988 (sea level) is calculated by subtracting water level (below land-surface datum) from land-surface elevation. Land-surface elevation is accurate to plus-or-minus 0.05 feet based on a differential GPS survey on 20 August 2016.  Water elevation accuracy is the sum of the water level (below land-surface datum) and land-surface elevation accuracy, or about ±0.15 feet.

WATER-QUALITY RECORDS

WELL CHARACTERISTICS - Depth 5.31 ft. Upper casing diameter 1.57 in; top of first opening 2.69 ft, bottom of last opening 4.73 ft. Piezometer NTR2-3A was installed using several sections of 3.25-inch-diameter Geoprobe rods to a depth of 5.5 feet. The piezometer is constructed of a 2.04-feet-long, 1.5-inch-diameter, schedule-40 PVC, 0.010-inch slotted Hole Products Inc. well screen, flush threaded to length/s of 5.00 feet of 1.5-inch-diameter, schedule-40 PVC well casing. The piezometer casing measuring point (stickup) was 1.58 feet (1341.11 ft. NAVD88, +/- 0.05 ft.) above land surface when measured on 27 April 2016. The open interval of the piezometer is between 2.69 and 4.73 feet below land surface and the total well depth is 5.31 feet below land surface.

This piezometer is screened in glacial till/clay sediment, which is overlies bedrock.

DATUM - Land-surface datum is 1,339.53 ft above North American Vertical Datum of 1988. Measuring point: This initial MP height was cut on 2016-04-27, 2.22 ft above land-surface datum, Apr. 26, 2016 to Apr. 26, 2016; Black mark on top of PVC well casing, 1.58 ft above land-surface datum, Apr. 27, 2016 to present.

The current measuring point is a black mark on the top of the white PVC 1.5-inch diameter well casing, which was 1.58 feet above land surface on 27 April 2016. Elevation of the measuring point is 1341.11 plus-or-minus 0.05 feet above sea level, North American Vertical Datum of 1988, based on differential GPS survey on 20 August 2016.

The original/initial measuring point was a black mark on the top of the white PVC 1.5-inch diameter well casing, which was 2.22 feet above land surface on 26 April 2016. Elevation of the measuring point is 1341.75 plus-or-minus 0.05 feet above sea level, North American Vertical Datum of 1988, based on differential GPS survey on 20 August 2016.

PERIOD OF RECORD -

Water Temperature:

Water temperatures were recorded hourly from 16 March 2017 at 17:30 CDT to 30 October 2018 at 09:45 CDT, except during the following periods:

30 Aug. 2017 at 09:30 CDT to 02 Nov. 2017 at 14:45 CDT: due to full transducer memory; newest data did not over-write oldest data.

18 Feb. 2018 at 05:15 CST to 06 Mar. at 07:30 CST: due to water level dropping below bottom of transducer.

13 Aug. 2018 at 17:30 CDT to 07 Sept. 2018 at 20:30 CDT: due to water level dropping below bottom of transducer.

25 Sept. 2018 at 02:00 CDT to 30 Oct. 2018 at 09:45 CDT: due to full transducer memory; newest data did not over-write oldest data.

Specific Conductance:

Specific conductance were recorded quarter-hourly from 16 March 2017 at 17:30 CDT to 30 October 2018 at 09:45 CDT, except during the following periods:

30 Aug. 2017 at 09:30 CDT to 02 Nov. 2017 at 14:45 CDT: due to full transducer memory; newest data did not over-write oldest data.

14 Feb. 2018 at 10:30 CST to 21 Mar. at 12:30 CST: due to water level dropping below bottom of transducer/sensor.

11 Aug. 2018 at 17:00 CDT to 09 Sept. 2018 at 10:00 CDT: due to water level dropping below bottom of transducer/sensor.

25 Sept. 2018 at 02:00 CDT to 30 Oct. 2018 at 09:45 CDT: due to full transducer memory; newest data did not over-write oldest data.

COOPERATION - This site was operated (2016-2018) by the U.S. Geological Survey as a monitoring piezometer for the Southeast Minnesota Subsurface Drainage Impacts on Groundwater Recharge study. The piezometer began to be used as part of the Southeast Minnesota Subsurface Drainage Impacts on Groundwater Recharge study during 26 Apr. 2016 to 29 Oct. 2018. The GW Drainage Recharge study is a collaborative effort between the Environment and Natural Resources Trust Fund (via Legislative-Citizen Commission on Minnesota Resources (LCCMR)) and the U.S. Geological Survey.

INSTRUMENTATION - Water temperature and specific conductance are measured with an Solinst Levelogger LTC 3001 submersible pressure transducer accurate to +/- 0.1°C. Temperature differences are accurate to 0.1°C.

REMARKS - Shifts in the specific conductance dataset are due to the removal of the transducer/sensor during site inspections and/or calibration checks. The removal and re-deployment of the transducer/sensor causes enough mixing in the piezometer to change the specific conductance signature in the piezometer. These shifts were real changes in specific conductance data that were measured in the piezometer, therefore, they were left in the specific conductance record.