National Park Service


Date of this Version



Natural Resource Report NPS/NGPN/NRR 2019/1909 / NPS 920/152042, April 2019: vi, 32 pages

Published by the United States Department of the Interior, National Park Service, Natural Resource Stewardship and Science, Fort Collins, Colorado

Also available at:

Please cite this publication as:

Ashton, I. W, J. S. Mills, M. Ohms, D. Austin, M. Wiles, and K. Paintner-Green 2019. Protocol implementation plan for cave water quality monitoring in the Northern Great Plains Network: Narrative version 1.0. Natural Resource Report NPS/NGPN/NRR—2019/1909. National Park Service, Fort Collins, Colorado.


United States government work. Public domain material.


Executive Summary

The Northern Great Plains Inventory and Monitoring Network includes thirteen park units located in five northern Great Plains states across six ecoregions. Two park units, Jewel Cave National Monument (JECA) and Wind Cave National Park (WICA), protect significant cave resources. These two caves are among the longest caves in the world and have an assortment of underground water resources ranging from drip sites to cave lakes. Subsurface water quantity and quality in the caves is a concern due to groundwater depletion and groundwater contamination from pesticides (aboveground applications), hydrocarbons (vehicle use and related activities), and wastewater effluent (sewage systems). Proper monitoring of cave water quality is critical to protecting the resource and preventing it from surface pollution.

The goal of the NGPN Cave Water Quality Protocol Implementation Plan is to determine the current condition and detect changes in select water quality parameters and contaminants in two significant groundwater lakes at both JECA and WICA. In collaboration with the parks, NGPN will monitor cave water quality using methods developed by the United States Geological Survey (USGS) in the National Field Manual. The USGS methods are used to monitor surface and groundwater quality around the nation, and only minor modifications are required to adapt them for cave environments. Water quality samples will be collected from two groundwater lakes once every three years and analyzed by a USGS laboratory for physical characteristics, nutrients, hydrocarbons, and metals. The groundwater lake sites were chosen because they are important park resources, can be accessed reliably, and there is an existing record of water quality data.

Reporting will consist of brief data reports every three years that summarize laboratory results. After nine years, a synthesis report will be completed. At this time, these water quality data can be compared to any other information pertaining to cave water collected by the parks during the same time period. Implementation of this protocol is designed to evolve over time, with a continual evaluation of site selection and water quality parameters to be measured as new cave passages and waterbodies are discovered.