Solinst Portable Electronic Water Level Meter Series

Overview

The Solinst Portable Electronic Water Level Meter Series is a field-proven family of precision groundwater measurement instruments engineered for reliable, repeatable determination of water level elevation, interface thickness, and multi-parameter profiling in monitoring wells and boreholes. Each model employs the principle of electrical conductivity detection—where a low-voltage circuit is completed upon contact between the sensor tip and conductive liquid (e.g., groundwater, saline water, or hydrocarbon-contaminated water)—triggering an audible tone and visual LED indicator. This robust, battery-powered design eliminates reliance on external power sources and ensures operation in remote or off-grid locations. All models integrate calibrated, metric-graduated measuring tapes with millimeter-scale resolution (1 mm minimum graduation), enabling direct depth reading without post-processing. The series adheres to ASTM D4044 (Standard Test Method for Determination of Water Level in a Borehole) and supports GLP-compliant field documentation when used with standardized logging protocols.

Key Features

• Field-deployable, lightweight construction with rugged carrying case for rapid mobilization and storage
• Integrated 9 V alkaline battery power supply (standard across models 101, 102, 107, and 122); typical operational life exceeds 90 hours for model 107
• Millimeter-precise metric tape calibration traceable to NIST-traceable standards; tapes available in lengths from 10 m to 1800 m
• Dual-sensor configuration options across models—including standard stainless-steel probes and compact 6 mm diameter coaxial probes optimized for narrow-diameter wells (≤5 cm)
• CSA-certified intrinsically safe design for model 122, approved for use in Class I, Division 1 hazardous locations per CSA C22.2 No. 157
• Corrosion-resistant materials: stainless-steel tape (model 103), chemically inert sensor housings, and oil/solvent-tolerant cable jackets suitable for LNAPL/DNAPL environments

Sample Compatibility & Compliance

The Solinst Water Level Meter Series is validated for use in PVC, stainless-steel, and HDPE monitoring wells ranging from 2.5 cm to 30 cm in diameter. Model 102’s 6 mm probe is compatible with 5 cm (2-inch) wells and smaller, while model 122 maintains accuracy in hydrocarbon-saturated zones where conventional sensors may foul or degrade. All units comply with ISO/IEC 17025 requirements for field instrumentation used in environmental monitoring laboratories. Model 107 meets US EPA Method 9060A specifications for in-situ conductivity profiling and supports temperature compensation algorithms aligned with ASTM D1125. Data collection workflows are compatible with FDA 21 CFR Part 11–compliant electronic lab notebooks when paired with auditable field log templates.

Software & Data Management

While the core meters operate as standalone field tools without onboard data logging, optional accessories—including the Solinst Levelogger software suite and Bluetooth-enabled adapters—enable digital capture of depth, temperature, and conductivity readings directly into secure, timestamped CSV or Excel-compatible files. All firmware updates and calibration certificates are distributed via Solinst’s secure customer portal, which maintains version-controlled audit trails for instrument firmware, sensor calibration history, and user access logs. Field technicians can generate GLP-compliant survey reports using preformatted templates that embed GPS coordinates, operator ID, well ID, and environmental conditions—ensuring full traceability from measurement to regulatory submission.

Applications

• Long-term groundwater level monitoring for aquifer sustainability assessments and drought response planning
• LNAPL/DNAPL thickness quantification in UST/LUST sites per ASTM E2857 and EPA OSWER Directive 9355.0-11
• Multi-level monitoring well (CMT, MP, or Waterloo system) installation verification and depth-to-stratum validation (e.g., model 103 for sand/bentonite placement confirmation)
• In-situ vertical profiling of electrical conductivity and temperature gradients to identify salinity intrusion, contaminant plumes, or geothermal anomalies
• Regulatory compliance reporting for state groundwater programs (e.g., California GAMA, Texas TWDB) and federal RCRA/CERCLA site characterization

FAQ

What is the maximum recommended tape length for accurate depth measurement under field conditions?

For optimal tension control and minimal tape sag error, Solinst recommends limiting single-drop deployments to ≤300 m for standard stainless-steel tapes. For depths beyond 300 m, users should employ tension-assisted deployment techniques or select the reinforced 1800 m tape variant with integrated counterweight reel assembly.

Can model 107 be used for continuous profiling, or is it strictly for discrete point measurements?

Model 107 operates in discrete-point mode only. For continuous conductivity/temperature profiling, Solinst recommends the Levelogger Edge with TLC probe or the Solinst TLC Profiler system.

Is calibration required before each field use?

Field verification using a known reference depth (e.g., calibrated well marker or bench-test water column) is recommended prior to critical measurements. Full sensor calibration is performed annually or after exposure to extreme chemical contamination, following Solinst’s documented calibration procedure SOP-SL-107-CAL.

Are replacement tapes and sensors available separately?

Yes. All tape lengths, probe diameters (6 mm and 10 mm), and coaxial cable assemblies are stocked as certified spare parts with serialized calibration certificates. Stainless-steel model 103 marking rope is supplied with certified tensile strength test reports (min. 1,200 kg breaking load).