Research & Data

Current GIS Data for Delaware County: includes imagery, floodplains, property parcels, soils, etc. This is also available as ArcGIS files.

See Delaware County GIS online site

DelCo Water Co. water sampling locations and data (2016-17)

Upper Olentangy Watershed Management and Action Plan
The Olentangy Watershed Alliance, 2006

“The purpose of this Plan is to provide watershed stakeholders an adaptive strategic framework for action that protects water resources currently meeting attainment standards, and restores water resources currently not meeting attainment goals. This plan represents the culmination of extensive field surveys, technical analyses, public participation and outreach, and documentation of the knowledge from an array of watershed stakeholders.”

PDF (26mb) here.

Delaware Run Floodplain: Preserving Nature in an Urban Landscape. Jed Burtt, 2015

PDF here.

The floodplain of the Delaware Run is unusual geologically and biologically. Geologically the Delaware Run, unlike other tributaries of the Olentangy River which flow through narrow, deep ravines, has carved a wide floodplain despite being a narrow stream. This wide floodplain provides the only naturally vegetated corridor into the city of Delaware, Its mix of eastern deciduous forest, brushy edges, and fields are host to an unusually diverse assemblage of birds. These are permanent residents, summer residents, winter residents and seasonal migrants. As a collection of birds they are the most abundant and diverse assemblage in the city, which is a strong reason for preserving the flood plain intact. Furthermore, the corridor also boasts diverse communities of butterflies, mammals and other vertebrates. Delaware Run flows east from a spring in Gallant Woods Metro Park. Extending Lexington Blvd. through the flood plain to connect Williams St. and Central Ave will disrupt the flow and create a substantial barrier to the movement of species along the natural corridor bordering the Delaware Run. Several alternatives to building a road through the floodplain are possible. Not building the road is the least expensive possibility. A second, expensive alternative is to build a road down into the flood plain clear cut the berms and put in a low culvert for the Run. The third, more expensive alternative is to build an elevated roadway over the flood plain thereby allowing free flow of the Run and the animals of the flood plain, leaving the habitat largely undisturbed. The advantages and disadvantages of these alternatives are discussed.

1940-1993 Research and Data Collection, Gatz et al

Gatz, A. J. and Harig, A. L. (1993) “Decline in the Index of Biotic Integrity of Delaware Run, Ohio, over 50 Years.” The Ohio Journal of Science. 93, 95-100.

PDF here.

  • Dr. Gatz and Dr. Harig did an assessment on biotic integrity of the Run from 1940-1993
  • Degradation had already started by 1940
  • As the population grew so did the rate of degradation, 9,000 to 20,000 people
  • Agricultural and urban runoff increased which included chemicals from the fields and petroleum products
  • Erosion of the run began to increase and loss of riparian vegetation occurred
  • Decrease in certain species that were found in 1940 but not in 1993
  • Most species present were pioneer species which showed an unstable environment
  • Also found an increase in deformities, eroding fins, lesions and tumors

1999 Research and Data Collection

  • Assessment done of all the tributaries in Delaware county
  • The run had the highest degree of metal contamination
    • Alumnium
    • Chromium
    • Copper
    • Zinc
      • o Polluted runoff from city streets, car brakes, concrete, gutters etc
      • o E.Coli was found along with sewage contamination increased  and pesticide runoff
      • Sulfurous ground water was seeping into the river
        • Bad Odor and whitish precipitate
        • Only tolerant fish and macro-invertebrate were found in the water
        • More pioneering species of fish were found in the run than sensitive environmental fish

2002 Research and Data Collection

  • Ecological assessment conducted by FLOW
  • The run no longer met the WWH (Warmwater Habitat) Standards
    • WWH: Capable of supporting and maintaining a balanced community of warmwater aquatic organisms. This is the most widely applied use designation assigned to warmwater rivers and streams in Ohio
    • Believed to be because of the increase in
      • Phosphorous
      • Contaminated sediment runoff
      • Habitat modification and sewage
      • Species of fish and micro-invertebrates followed the trend of more than half being pioneer species

City of Delaware’s Plan for Restoration

  • Kristen Piper, Watershed Coordinators of the Upper Olentangy
  • Fixing the falling wall near Sandusky Street
    • Strengthen the bridge
    • OSHA Codes
      • Making the banks the required height by sloping them
      • Removal or saving of the large trees on the banks

Short Term Efforts

  • River Clean Up: teaming up with the Wildlife and Environment Club along with other students from OWU, Delaware Run clean ups will be scheduled; partners will pick up debris that has fallen into the water and around the run.
    • These clean ups can also be a chance for students to remove the invasive species that have covered the banks such as Japanese Honeysuckle and Princess Tree.
    • Ecological Studies can begin immediately to measure the abiotic and biotic factors of the run.  At OWU there are professors that teach parasitology, ecology, entomology, and ornithology.  The run would allow them place to have field lectures and lab while also monitoring the ecological growth.


Gatz, A. J. and Harig, A. L. (1993) Decline in the Index of Biotic Integrity of Delaware Run, Ohio, over 50 Years. The Ohio Journal of Science. 93, 95-100.

State of Ohio Environmental Protection Agency. (1999) Biological and Water Quality Study of the Olentangy River and Selected Tributaries 1999, Delaware and Franklin Counties, Ohio.  Ecological Assessment of Division of Surface Water. 1-98.

FLOW’s Watershed Inventory. (2002)

Interview with Kristen Piper, Watershed Coordinator of Upper Olentangy, November 12, 2013.

Research on community reactions to recreational trail development in Delaware, Ohio (Tim Hawthorne, John Krygier)

Mapping ambivalence: Exploring the geographies of community change and rails-to-trails development using photo-based Q method and PPGIS (click for download)

As the literature on trail development suggests, recreational trail projects can generate conflicts and controversies, particularly when built on abandoned rail corridors through developed areas. These conflicts are often understood as ‘‘not in my backyard” (NIMBY) reactions, suggesting a spatial proximity to conflict which increases as one draws closer to the proposed trail. This research seeks to understand local residents’ perceptions and reactions to recreational trail development in the City of Delaware (Ohio, USA). It addresses two spatially infused questions: Does the potential for conflict related to trail development increase as people live closer to a potential trail (the NIMBY factor)? Can important qualitative factors about favorable and unfavorable land uses including potential recreational trail sites be defined using a participatory methodology and then represented in GIS?