Lake Carl Blackwell Dam
OSU’s Lake Carl Blackwell dam, constructed in 1937–38, is an earthen structure with a concrete spillway that provides drinking and irrigation water to OSU and supports recreation as well as university, state and federal research.
The dam was built to construction standards in place in the 1930s and needs rehabilitation to meet modern standards. OSU has completed rehabilitation design work, continues inspection and maintenance, and is pursuing construction funding so Lake Carl Blackwell dam repairs can move from design to construction.
OSU dam maintenance
- OSU inspects the dam weekly with a walk-through and monthly with a high accuracy survey. This is well above and beyond federal and state requirements. The dam is inspected annually by a registered professional engineer in accordance with state and federal requirements.
- When water is flowing over the spillway, the dam is inspected daily.
- OSU maintains the dam. Typical maintenance includes removing trees, plugging animal burrows, ensuring a healthy cover of grass, repairing the concrete spillway and restoring “riprap” (rock armoring on the lake side of the dam).
- OSU partners with the university’s Oklahoma Aerospace Institution for Research and Education to use drones to monitor the dam as needed, such as after earthquakes in the area.
At a glance:
- High Hazard Classification: due to potential downstream impacts if failure occurred. This classification reflects potential for loss of life, not dam condition.
- Poor Rating by the Oklahoma Water Resources Board (OWRB) due to seepage, past soil movement, and steep slopes that don't meet modern standards. (The “poor” rating is defined by federal and state dam programs.)
- Rehabilitation need is urgent. While there is no imminent threat, rehabilitating the dam is an urgent priority.
FAQs:
Has the lake ever gotten so full during a time of flood, that the water has overtopped the dam?
No. There have been significant times of flooding that have affected Stillwater and surrounding areas in the last 90 years, but the water in the lake did not reach the top of the dam. The lake’s largest flood event flowed five feet deep over the spillway and was still eight feet away from the top of the dam.
I have heard that the Lake Carl Blackwell dam is a "high hazard" dam. What does that mean?
The Oklahoma Water Resources Board Dam Safety program defines the hazard potential for dams in Oklahoma. The dam is classified as high-hazard due to potential downstream impacts if failure occurred — this classification reflects potential loss of life, not dam condition.
I have heard that Lake Carl Blackwell dam is in poor condition. What does that mean?
During the latest annual inspection of the nearly 90-year-old dam in October 2024, the dam’s condition — specifically the downstream slope — was rated as “poor” by the Oklahoma Water Resources Board due to existing seepage and past soil movement. The “poor” rating is defined by federal and state dam programs. While there is no imminent threat, rehabilitating the dam is an urgent priority.
Are there other "high hazard" dams near Stillwater? What are their conditions?
Yes. Lake McMurtry, Boomer Lake, Hazen Lake, as well as the dams at Karsten Creek, University Estates, Whittenburg Park, Lakeside golf course, and the stormwater detention area at Hall of Fame and Western are considered "high hazard.” The “high hazard” classification has to do with potential downstream impacts if failure occurred, not the condition of the dams. You can learn more about these and other dams at the U.S. Army Corps of Engineers' National Inventory of Dams (NID) web site.
Does the LCB dam meet modern dam construction standards?
No. It met the standards of dam construction in the late 1930s when it was built. It does not meet today’s standards, primarily because of the steepness of the back slope. To address the dam’s “poor” rating, a dam project is needed to improve the back slope to modern standards.
What is the dam project?
OSU applied for and received the FEMA High Hazard Potential Dam grant funding in 2019. The money was used to hire a professional engineer, who developed construction drawings to rehabilitate the dam. Those drawings are complete and ready for construction. OSU is actively pursuing grants and legislative support for the cost of implementing the plan, which is more than $20 million.