Gerwig Lane Swm
Gerwig Lane Swm is an earth dam located in Howard County, Maryland, built in 1980. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Gerwig Lane Swm
The primary purpose of Gerwig Lane Swm is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by Howard County (local government). It impounds the Little Patuxent River-tr.
Completed in 1980, the dam is 46 years old.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 05/02/2024.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Maryland dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Maryland |
| County | Howard |
| River/Stream | Little Patuxent River-tr |
| Coordinates | 39.17364, -76.84780 |
Physical Characteristics
| Dam Type | Earth |
| Year Completed | 1980 (46 years old) |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | Howard County |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 05/02/2024 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | MD00579 |
| Federal ID | MD00579 |
| More Info | State Dam Safety Program |