Olentangy River Watershed

The Olentangy River flows 88.5 miles from its headwaters in Crawford and Richland County through Marion and Morrow County into the City of Delaware and ending in Franklin County at its confluence with the Scioto River.

The Olentangy River has a drainage area of 536 square miles. Twenty-two miles of the Olentangy were designated a state Scenic River by the Ohio Department of Natural Resources in 1973.

The designation runs from the Delaware Dam, north of the City, to Wilson Bridge Road in Worthington.


Everyone lives in a watershed and the City of Delaware is located in the Olentangy River watershed. A watershed is an area of land that directs surface water and ground water towards a single body of water. A ridge separates one watershed from another and will drain the water in different directions.

Each watershed can be broken down into subwatersheds or increased into larger watersheds. If the Olentangy River watershed was broken into smaller subwatersheds, some residents in the City of Delaware would live in the Delaware Run subwatershed, while others would live in the Sugar Run subwatershed. There are several other small waterways connecting to the Olentangy River that would be additional subwatersheds.

If the Olentangy River watershed was increased into larger watersheds, the Delaware City residents could say they live in the Scioto River watershed. Since the Olentangy drains into the Scioto River this would be a true statement. This also makes our watershed the Ohio River, Mississippi River, and Gulf of Mexico.  


On June 21st, the first annual Northern Olentangy Watershed (NOW) Festival will be held at Mingo Park in the City of Delaware. This festival is designed to celebrate our watershed. There will be several demonstrations, activities, and workshops for children and adults. The children can creatively play at the scrap play area, participate in the scavenger hunt with the Delaware Soil and Water’s soil tunnel, explore in the river with a representative from Ohio Department of Natural Resources, catch “bugs” in a dry stream, talk to Corey-the Army Corps of Engineer’s lifeboat, and learn about our river from many experts throughout our community. Adults may be more interested in learning about our drinking water, invasive species in our area, how plants can filter pollutants out of our waters, the agricultural 4R program, our local parks system, or how to install a rain garden. There will also be a rubber duck race, a conservation award, and a rain barrel painting raffle.

Currently the call for nominations is open for the Conservation Award. If you or someone you know live or work in the Upper Olentangy Watershed and you think they make a difference, please consider filling out the nomination form.
Conservation Award Guidelines and Nomination Form

If your business is located in the Upper Olentangy Watershed and would like to fund a rain barrel to paint, please read the instructions and fill out the order form.
Rain Barrel Painting Raffle


April 4th - Rain Barrel Workshop - 6:30, 7:30 & 8:30pm
                 @ FirstFriday Festivities
May 2nd - Rain Barrel Workshop - 6:30, 7:30 & 8:30pm
                 @ FirstFriday Festivities
June 21st - Watershed Festival
                 @ MingoPark (noon-3:30pm)


Spring 2013
Fall 2013
Winter 2013
Spring 2014

HOW CAN YOU PROTECT THE Olentangy River Watershed:
City Watershed Coordinator Kristin Piper can be reached at 740-203-1905.

Drains to River Brochure
Storm Water Quality Implementations Brochure
Pet Waste Removal Flyer

Olentangy Watershed Alliance                       Crawford County Health Department
Crawford County SWCD                                 Delaware County Health Department
Delaware County SWCD                                 Marion County Health Department
Marion County SWCD                                    Morrow County Health Department
Morrow County SWCD                                   Richland County Health Department
Richland County SWCD
Ohio EPA
ODNR - Division of Soil and Water