Hillen Road Water Supply Tank
Hillen Road Water Supply Tank is an other dam located in Baltimore City, Maryland, built in 1920. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Hillen Road Water Supply Tank
The primary purpose of Hillen Road Water Supply Tank is water supply. The dam stores water for municipal, industrial, or agricultural use, helping ensure a reliable supply for the surrounding area. The dam is owned by Baltimore City Dpw Reservoir Section (local government). It impounds the Offstream-herring Run near Baltimore City.
The dam stands 36 feet tall and stretches 500 feet across, creates a reservoir covering 6 acres, has a maximum storage capacity of 84 acre-feet, and collects water from a drainage area of 0 square miles. Completed in 1920, the structure is over a century 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 11/21/2024.
At 36 feet, this dam is taller than 83% of dams nationwide.
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 | Baltimore City |
| Nearest City | Baltimore City |
| River/Stream | Offstream-herring Run |
| Coordinates | 39.33361, -76.58944 |
Physical Characteristics
| Dam Type | Other |
| NID Height | 36 ft |
| Dam Height | 36 ft |
| Dam Length | 500 ft |
| Year Completed | 1920 (106 years old) |
Storage & Hydraulics
| NID Storage | 84 acre-ft |
| Max Storage | 84 acre-ft |
| Normal Storage | 64 acre-ft |
| Surface Area | 6 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 42 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Water Supply |
| Owner | Baltimore City DPW Reservoir Section |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 11/21/2024 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | MD00363 |
| Federal ID | MD00363 |
| More Info | State Dam Safety Program |