NWDTW 2024

This training is intended to go over the data processing of basic discrete and time-series groundwater data. Content will include a mix of presentations, demos, and discussions.

Groundwater flow meters that measure horizontal groundwater flow direction and velocity have been used in several different investigations by the USGS across the nation. Historically, flowmeters were used to measure groundwater flow related to contaminant plumes (TCE, PFAS, etc.) to assist in remedial actions or site characterizations in in relation to aquifer tests to determine the area of influence from groundwater production. Recently, as part of the NGWOS Illinois Basin Study, groundwater flowmeters have been deployed at real-time continuously recording stations at two field sites to help quantify groundwater and surface water interactions between streams and the surrounding agricultural setting. This presentation will include an overview of the available technologies, proper deployment and use, case studies and best management practices.

This presentation will cover the essential issues for those involved in the groundwater sampling effort for the National Water Quality Network. Some field sampling issues will be discussed. However, the focus will be on the cycle of management and the importance of the steps needed to maintain the networks at optimal size, provide timely flow of data, and how the various forms and data provided by the sampling crews are used. The presentation will discuss these issues from the user's perspective so that the sampling crews have a better understanding of the essential steps to ensuring the health and longevity of the network to evaluate groundwater quality trends in the nation.

This session is an open forum for general groundwater discussion, and for representatives from Hydrologic Networks Branch and Office of Quality Assurance to discuss and listen to topics and concerns from USGS scientists.

Groundwater Site Inventory (GWSI) version 5.2 is a menu-based data storage and management system on the UNIX platform that is nearing end-of-life and requires modernization. GWSI includes site inventory information and groundwater thematic metadata and is considered part of legacy National Water Information System (NWIS). GWSI is currently in the process of being replaced by modern solutions as part of the NWIS Modernization Program, and the legacy product will be retired by the end of Fiscal Year 2025. By that time, all data stored within legacy GWSI will either be deprecated and archived or migrated to one of three locations: Monitoring Location Registry (MLR), AQUARIUS Time-Series (AQTS), or the new GroundWater Information System (GWIS) database, pronounced as “GeeWhiz”. In this presentation, we will outline the plan for completing modernization, provide updates on our progress so far, and discuss requests for help from Water Science Center Local Data Managers (LDMs) on several cleanup tasks associated with archival and migration.

This talk will provide an overview of the newly augmented flag criteria used by the OQA’s Time-Series Check tool for groundwater levels. The tool compares site-visit-collected electronic readings and tape downs for publicly viewable groundwater levels, and flags discrepancies that likely indicate errors. The tool has always incorporated the uncertainty of the tape-down measurement, and now it also incorporates the uncertainty of the electronic reading. The discussion will address uncertainty of electronic readings and of tape downs, including uncertainty fields in SVMAQ and AQTS and uncertainty computations for electronic readings based on manufacturer technical specifications.

This talk will present a basic overview of continuous groundwater data collection including discussion on site selection and conditions, and equipment selection, calibration, and installation. Procedures for a general site visit including discrete measurement, data download, equipment servicing, and site maintenance will be included.

As part of NGWOS efforts in the Delaware River Basin, a soil moisture sensing testbed was developed at a continuous records observation well, DE 723. Both proximal and in-situ sensors were installed utilizing both novel and traditional technologies. Likely the precursor to a soil moisture sensing techniques and methods (T&M), practices are being developed for calibration, installation, verification, and analysis. Over 100 time-series are being maintained and reviewed using AQ Time-Series. Beyond soil moisture content other time-series include meteorological parameters (i.e. solar flux, precipitation, wind speed, etc), cosmic ray neutron counts, and soil temperature. Discrete measurements used for verifying in-situ and proximal soil moisture sensors are also being made and include soil core grab samples, downhole nuclear magnetic resonance logs, and handheld soil moisture "check measurements". These efforts are advancing the USGS's ability to quantify water being stored in the soil zone, while also characterizing an underrepresented phase of the water cycle. Future work regarding computation of infiltration and recharge rates, prediction of streamflow responses, and quantification of drought conditions will all benefit from long-term soil moisture records established by the USGS.

The USGS, in cooperation with the Massachusetts Department of Conservation and Recreation, has upgraded 23 groundwater monitoring wells in Massachusetts from discrete to continuous real time monitoring in the past three years, with plans for additional upgrades to the network in the coming years. The climate response network (CRN) status was also evaluated and updated for all groundwater monitoring wells. This presentation will describe methods of this network analysis including 1) computer tools used in a preliminary desktop analysis, 2) field evaluation of groundwater wells, including temporary data collection and well integrity assessments, and 3) installation of the real time groundwater monitoring equipment. Next steps and future opportunities for this long-term groundwater monitoring network will also be highlighted. Gain insights into evaluating your own networks!

Discuss the importance of well integrity and methods for evaluating.

All methods of taking groundwater-level measurements have uncertainty associated with them, and these uncertainties can be numerous and compounded. Uncertainty sources can be the instrument used for measuring the groundwater level, the equipment used to validate the measured groundwater level, conditions in and near the well, environmental conditions, and even the person measuring the water level. Variables that can affect uncertainty can include temperature, measurement depth, tape stretching or other irregularities like kinks, and well access and construction. Some sources of uncertainty are identified and quantified through testing and laboratory analysis however, some uncertainty can be subjective and require a hydrographers best judgement when in the field. In this brief presentation, various sources and variables of uncertainty will be presented with a discussion to follow on other experiences with uncertainty in groundwater-level data collection.