Oregon Water Resources Department

Link to:  Oregon Water Resources Department Groundwater Information

NGWMN Contact:

Justin Iverson

503-986-0933

justin.t.iverson@oregon.gov

  

The Oregon Water Resources Department (OWRD) is a water-level data provider to the National Groundwater Monitoring Network (NGWMN). The OWRD collects this data to evaluate aquifer sustainability, the impacts of groundwater withdrawals on surface-water sources, and the availability of groundwater for new proposed uses. OWRD currently measures water levels in about 1300 wells across the state, and serves data from 280 sites to the NGWMN Portal. OWRD has been a part of the Network since 2015. 

OWRD provides water-level data from the Willamette-Lowland basin-fill aquifers, Pacific Northwest basin-fill aquifers, Pacific Northwest basaltic-rock aquifers, Columbia Plateau basin-fill aquifers, and Columbia Plateau basaltic-rock aquifers. 

NGWMN Projects:

2015: 10/1/2015 to 9/30/2016

Initial project to become a NGWMN data provider.

2017: 7/1/2017 to 6/30/2019

Project is to provide persistent data services, do site-information gap drilling, and drill a replacement NGMWN well. The work for persistent data services is for two years. Work under site information gap filling consists of 3 parts. Lithologic and well construction information will be entered from paper files, historic continuous water-level data will be entered into new database so that it is available to the NGWMN, and a GPS survey will be conducted at 63 wells to get more accurate locations and altitudes. The final part of the project is drilling a replacement well in the Columbia Plateau basaltic-rock aquifer. 

2019 Round 1: 7/15/2019 to 7/14/2021

Project is to add NGWMN Sites, provide persistent data services, and fill gaps at NGWMN sites.  New sites will be added in the Portland Basin as an effort to build an interstate monitoring network of the Pacific Northwest Basin Fill aquifer in the area. Gap filling work involves evaluating and adding historic water-level data and reconciling their data with USGS data.

2021: 11/1/2021 to 10/31/2023

This project is to provide persistent data services, drill a new well to fill a network gap, and replace existing water-level monitoring equipment at 11 wells.

NGWMN Presentations:

December 2016 presentation to SOGW 

Site Selection and Classification

Site Selection

Selection of Oregon sites for the NGWMN was an iterative process that was completed independently for each of the 18 major drainage basins in the state. Where major structural features produce natural boundaries in the groundwater flow system, sub-basins were evaluated independently so that a set of representative sites could be selected in each of the major groundwater flow systems in the state. 

In each basin, all current OWRD observation wells were reviewed to determine the frequency of water-level measurements, the period of record, and the completeness of the minimum data elements specified in the NGWMN Framework Document and the Minimum Data Elements tip sheet. Each well was then associated with a Principal aquifer as defined by the USGS (U.S. Geological Survey, 2003; Whitehead, R.L., 1994). For each Principal aquifer, the spatial distribution of wells was reviewed using GIS software. A core set of "Trend" wells was selected from the State Observation Well Network using selection criteria in the Framework Report and the Well Selection Criteria for Water Levels tips sheet. In cases where the spatial distribution of "Trend" wells was inadequate, additional "Trend" wells were selected from other observation well networks. Preference was given to wells with continuous recorders installed, wells measured at least four times per year, wells with long periods of record, or dedicated observation wells recently drilled with state funds for the purpose of long-term monitoring. After a representative suite of "Trend" wells was selected, "Surveillance" wells were selected to complement the trend wells in each Principal aquifer. Some of the "Surveillance" wells have continuous recorders installed but many are generally measured quarterly or annually. The set of selected wells was then reviewed several times and adjustments were made to achieve the best possible spatial distribution for each Principal aquifer within each major groundwater flow system while ensuring good spatial and temporal patterns relative to human activity and climate variation. 

A total of 280 water-level monitoring sites were added to the NGWMN during the performance period and web services were established for discrete water levels, mean daily recorder water levels, lithology, & well construction. The wells represent five USGS principal aquifers and several locally important pre-Miocene bedrock aquifers. Sixty-seven of the wells have continuous recorders installed. All of the required data elements have been entered into the site registry.  

USGS Principal Aquifer Total Trend Surveillance
Columbia Plateau basaltic-rock aquifers 80 34 46
Columbia Plateau basin-fill aquifers 14 5 9
Pacific northwest basin-fill aquifers 70 31 39
Pacific northwest volcanic-rock aquifers 71 23 48
Willamette Lowland basin-fill aquifers 34 12 22
Other aquifers (Pre-Miocene bedrock) 11 6 5
Total 280 111 169

Site Classification 

Each well was classified into the Background, Suspected Changes, or Documented Changes subnetwork using the NGWMN tip sheet on Defining Monitoring Categories.

Data Collection Techniques

OWRD collects water-levels and well metadata using procedures and data collection standards that parallel those outlined in the NGWMN Framework Document and in Groundwater Technical Procedures of the U.S. Geological Survey. The Department uses steel tapes in a few wells but generally uses commercially available electric tapes from several vendors. Tapes are calibrated annually, or more frequently as needed, using a 500-foot dedicated steel tape that has been calibrated by the USGS Oregon Water Science Center. Calibrated flat tapes (electric tapes with a steel core) are used in all dedicated observation wells without pumps. Coaxial electric tapes are used in all wells with pumps. In flowing artesian wells, calibrated gages are used to measure shut-in pressure. A few of our NGWMN wells are measured using an airline and a calibrated gage. Whenever possible, independent calibrated electric tape measurements are made to verify airline lengths. 

Water-level measurement errors are initially assigned to each measurement based on the tool used to obtain the measurement as follows: 

Calibrated steel tapes .01 feet
Calibrated flat electric tapes .01 feet
Calibrated coaxial electric tapes .02 feet
Uncalibrated coaxial electric tapes .10 feet
Calibrated gage measurements used for shut-in pressures .25 feet
Calibrated gage measurements used for airlines with verified airline lengths 2 feet
Calibrated gage measurements used for airlines with unverified airline lengths  4 feet

However, these initial error estimates are adjusted upward as needed based on conditions encountered in the field. 

Measuring points are documented relative to land surface at each well as well as the horizontal and vertical errors associated with the well location and well-head elevation. All field measurements are recorded on dedicated paper forms and archived in a dedicated file for each observation well. OWRD's current database has the ability to capture all metadata now documented on paper forms. Records for each well are reviewed annually to assess the overall quality of the data and to assign a reliability index to individual measurements based on the entire record for the year. When time permits, historical records are reviewed in the same manner. 

OWRD does not currently have a formal groundwater field-collection manual. However, OWRD is in the process of developing a manual that will outline standard data collection, processing, and quality control procedures. OWRD anticipates providing this manual to the NGWMN in conjunction with future projects. 

Data Management

All current recorder data is processed and reviewed using WISKI, a time-series water-information management system developed by the KISTERS Company. A customized processing file is established in WISKI for each monitoring site based on unique site attributes. Standard protocols are used to subtract barometric pressure (most of our transducers are non-vented models), correct for drift using independent measurements made with calibrated electrical or steel tapes during each site visit, and correct for miscellaneous baseline shifts. Some of these processes are automated by the WISKI software, but each file is also reviewed at various times by a hydrogeologist to ensure that the final product meets our quality control standards. The data is also processed to provide a table of mean daily levels. The final, corrected unit measurements and the daily mean values are uploaded into SQL tables, which are then available to the NGWMN Portal through our web services. Historic recorder data will be processed in the same manner as time permits. 

OWRD does not currently have a formal groundwater field-collection manual. However, we are in the process of developing a manual that will outline our standard data collection, processing, and quality control procedures. We anticipate providing this manual to the NGWMN in conjunction with future projects. 

All data collected by the data provider (OWRD) is considered to be public information, but policy dictates that personal identification information will not be made readily available on web pages. Other than personal identification information, all data collected for this project is made available on our web pages or in response to written requests. Database security and privacy protocols required by the State of Oregon will ensure data security and privacy. 

Groundwater and well data collected by OWRD is generated with the intention of providing long-term data records for groundwater studies. Field-collection notes are stored in paper files in a central filing system. Field measurements are also stored in digital tables in an enterprise-level SQL database. Copies of the paper files are available upon request. Digital records will be publicly available through an on-line interface on the agency's web page. All digital files are backed up on tape and external disks. 

Other Agency Information

Web sites of Interest:

Agency use of monitoring data: