About Us

The Crawford Hydrology Laboratory is a nationally leading laboratory for groundwater flow investigations using fluorescent dye tracing with an emphasis on, but not limited to, karst landscape/aquifer systems. Established in 1979, we provide a range of technical, field, and laboratory services to a diverse, national and international clientele, including federal, state, and local agencies, environmental consulting firms, and individuals. We have extensive experience assisting clients with a variety of fluorescent dye tracing applications including groundwater basin delineation, sewage leaks, dam safety and remediation, contamination source determination, and spring protection. 

With over 50 years of combined experience and expertise, our staff offers cost-effective groundwater tracing solutions to help clients solve real-world environmental problems. We are available to assist clients at whatever level of engagement is needed. We can independently design, and manage complete groundwater investigations or simply provide supplies and analysis. Projects can be cost effective and we can custom tailor each project to the needs and resources of the client. We also offer expert opinion and reporting relating to karst hydrogeology for engineering and environmental projects.

Past clients include the National Park Service, Bureau of Land Management, U.S. Forest Service, and Army Corps of Engineers. We have provided services to clients in 36 states plus  Brazil, Canada, China, Italy, Mexico, New Zealand, Peru, Serbia, Ukraine, Vietnam, and Zimbabwe.  

Peruse our Statement of Qualification for more info.

Chris Groves joined the Center for Cave and Karst Studies, the original research group that would become the Crawford Hydrology Laboratory, as a student of WKU’s karst program founder, Nick Crawford, in 1981. His first dye traces were the following year. He is now University Distinguished Professor of Hydrogeology at WKU and CHL Director. He received a PhD in Environmental Sciences at the University of Virginia, and has since developed an active international research program in hydrogeology, geochemistry and water resources. 

Dr. Groves has helped lead several United Nations scientific programs, including as co-Leader of Project IGCP661 “The Critical Zone in Karst Systems” through 2021. He also serves on the Governing Board and Academic Committee of the International Research Center on Karst under the Auspices of UNESCO. He served as Associate Editor of Hydrogeology Journal, and has published in the field’s leading journals including Groundwater, Water Resources Research, Journal of Hydrology, and Geomorphology. 

Additionally, Dr. Groves has led cooperative research in hydrogeology and water resources of the extensive karst region of rural southwest China since 1995. During his 36thtrip to the country, in January 2017 China’s President Xi Jinping awarded Groves the China International Science and Technology Cooperation Award, that country’s highest honor for foreign scientists, for “great contributions to China’s hydrogeology and karst geology fields.”

For many years, Groves has studied and explored caves and surface landscapes of Mammoth Cave National Park, including service as an expedition leader, Director, and President of the Cave Research Foundation.

Ms. Bledsoe is the Associate Director of the Crawford Hydrology Laboratory. She provides project management, professional consultation on tracer test design, advises on hydrologic and water quality monitoring, oversees technical report writing, and supervises CHL staff and students. During her 16 years with CHL, she has worked on dye traces for groundwater basin mapping, effluent and sewer pipe break investigations, dam leaks, landfill expansions, determining groundwater flow routes from factories and quarries, and determining spring recharge areas for projects across the U.S. as well as China, Jamaica, and Brazil.  Ms. Bledsoe is a WKU Karst Field Studies instructor, serves as a technical advisor on undergraduate and graduate research at WKU and partner Universities, and leads dye-tracing workshops in the US and abroad. 

Before joining the Crawford team, she worked for private research institutes and the National Park Service on water quality, hydrology, ecosystem restoration, and public health research projects. She is a Registered Sanitarian with the Department of Public Health for the State of Kentucky and is a certified onsite wastewater disposal inspector. Ms. Bledsoe received her Bachelor of Arts in Environmental Science from Tusculum College and Master of Science in Geoscience from Western Kentucky University. Her thesis work was a collaborative effort with the United States Army Corp of Engineers to investigate groundwater flow in the vicinity of Patoka Dam in Indiana to support dam safety risk assessment.

Ms. Singer is the Lab Manager of the Crawford Hydrology Laboratory. Her experience at CHL includes groundwater basin delineation, characterization of groundwater flow, landfill expansions, sewer/septic leaks, underground storage tank releases, water source protection, and studies to inform water quality monitoring locations and evaluate the efficacy of existing groundwater monitoring programs on industrial sites. She supervises and executes day-to-day lab operations including sample processing and analysis, data interpretation, technical report writing, and the lab’s QA/QC program. She also serves as the lead field technician responsible for coordinating logistics as well as sample and data collection for both CHL research and client projects. 

Prior to joining the CHL team, Ms. Singer earned a Bachelor of Science in Professional Biology from the University of North Alabama in 2015 and completed a Master of Science in Geoscience from Western Kentucky University in 2017. Her thesis work, entitled "The Atmospheric Sink from Carbonate Rock Dissolution: The Ohio River Basin", focused on the geochemical sequestration of atmospheric carbon dioxide through interactions of acidic rainfall with carbonate rocks.

Ms. Lich is an undergraduate student majoring in biology, geology, and math in the The Mahurin Honors College at Western Kentucky University who grew up exploring and hiking caves and trails in Mammoth Cave National Park. Her research experience includes an ecology research internship at CloudBridge Nature Reserve in Costa Rica where she studied the relationship between the height of trees and the level of forest floor vegetation. As a Crawford Mahurin Cave Research Fellow in the Crawford Hydrology Lab, her interests focus on the intersection of geology and biology. 

Ava is completing her Mahurin Honors College capstone thesis project through the Crawford Hydrology Lab studying water filtration options for rural water users in South Central Kentucky.  

Ms. Dukes is a student of The Mahurin Honors College at Western Kentucky University and a Crawford Mahurin Cave Research Fellow.  Evie is from Paducah, Kentucky and is currently pursuing a triple major in Environmental Science, Chinese, and Spanish. Her interest in the natural world is evident from her biological research experience at Cloudbridge Nature Preserve in Costa Rica in 2022. She enjoys exploring nature via hiking, photography, and kayaking as well as raising a family of very cute ducks. 

 Samantha Zaboronak  is a sophomore in The Mahurin Honors College at Western Kentucky University and a Crawford Mahurin Cave Research Fellow.  Ms. Zaboronak is from Louisville, Kentucky and is a biology major with a chemistry minor. She serves as Vice President of Alpha Omicron Pi sorority and enjoys being involved in student affairs on campus.  Samantha won over the CHL team with her professionalism and dedication; "Ever since I was in middle school, I have loved science and math and am passionate about using my knowledge in these fields to help others one day! - SZ"

Teaming up with the WKU Biotechnology Center, Samantha will be combining her background in biology and chemistry, to investigate pathogens in karst drinking water sources using molecular techniques. Her research may hold significant implications for public health measures for off-grid communities and globally in areas where there is limited access to clean water.

Lauren Clark  is a sophomore in The Mahurin Honors College at WKU.  Hailing from Louisville, Kentucky, she is now studying biochemistry with a pre-medical concentration, hoping to pursue a career as a medical examiner. She is a member of several organizations such as Delta Zeta, Alpha Epsilon Delta (AED), American Medical Student Association (AMSA), Chemistry Club, Circle of Sisterhood, and Habitat for Humanity. She is a keyholder at Abercrombie & Fitch, where she has worked for 2.5 years. In Lauren's free time, she likes to volunteer with Habitat for Humanity, building sheds for those in need of affordable housing. 

Lauren's Honor's Thesis research will look at water quality and sustainability issues in the Mammoth Cave Biosphere Region with a particular focus on water resource management for public health.

 Sydney Friedman is a junior at WKU majoring in Environmental, Sustainability, and Geographic Studies who began working with CHL in Fall 2024. She is also minoring in music and completing certificates in Emergency Management Disaster Science and Geographic Information Systems. She explored Ireland on a Faculty-led study abroad trip in summer of 2023 where she created a story map about Ireland’s waste management practices. She has also completed projects about environmental ethics in Kentucky, global sustainability of the cocoa industry, and the Urban Heat Island Effect in Western and Central Kentucky. Outside of her major, Sydney is also active in the Music department where she plays oboe and percussion. She is a member of the professional music fraternity, Sigma Alpha Iota and a section leader in WKU’s Big Red Marching Band. 

 Jacob Sebastian is a sophomore from Cub Run, Kentucky who is majoring in Photojournalism and Environmental, Sustainability, and Geographic Studies. His favorite things are hiking, watching movies, and reading a good book. He will be working with the CHL leadership team on market research and digital communication efforts for all facets of our operation. 

Ms. Norman is a graduate researcher and student worker of the Crawford Hydrology Lab pursuing a MS in Geosciences from the Dept. of Earth, Environmental, and Atmospheric Sciences (EEAS) at Western Kentucky University. Originally from Louisville, KY, her research interests include microplastics, general contaminant transport, and water quality.  Katie's MS thesis research focuses on the impacts of microplastics on freshwater aquatic biota in karst environments.  

Katie is a 2023 graduate of The Mahurin Honors College at Western Kentucky University having earned dual majors in Biology, and  Environmental Science, Sustainability, and Geographic Studies. She is part of the Joint Undergraduate-Masters Program (JUMP) at WKU, which enabled her to earn credit toward a Master's in Geoscience while working on her undergraduate degree.  She completed her graduate work in August 2024, read her thesis here:  Landuse and Microplastic Transport in Karst Groundwater of South-Central Kentucky

Ms. Lane is a student of The Mahurin Honors College at Western Kentucky University and a Crawford Mahurin Cave Research Fellow. Katie is a senior working towards a BS in Environmental, Sustainability, and Geographic Studies as well as a certificate in GIS. Katie's capstone thesis project seeks to provide interpretive resources in American Sign Language to support cave tours at Mammoth Cave National Park. In addition, she conducts independent research on drinking water quality challenges to plain living communities in south-central Kentucky and evaluates the efficacy of low-cost passive filtration techniques to purify water.

After graduating in 2024, she is interested in working for the National Park Service or other related departments. Outside of her studies, Katie enjoys caring for all of her plants and hiking. 

Mr. Strehl was an undergraduate researcher of The Mahurin Honors College majoring in Geology and is a Crawford Mahurin Cave Research Fellow. Will's interests include speleology, karst, and hydrogeology. Will is an avid caver, and likes to spend much of his free time caving. His goal as an undergraduate student was to have as much exposure to different fields of geology as possible.  Will  studied the geology of Great Onyx Cave in Mammoth Cave National Park for his Mahurin Honors College capstone thesis project. He is now working with Ensafe, a national environmental consulting company.