Saw Mill
Saw Mill is an earth dam located in Montgomery County, Pennsylvania, built in 1968. It carries a High hazard potential classification and has a fair condition assessment.
About Saw Mill
The primary purpose of Saw Mill 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 Borough Of Norristown (local government). It impounds the Sawmill Run.
The dam stands 47 feet tall and stretches 1,335 feet across, has a maximum storage capacity of 740 acre-feet, and collects water from a drainage area of 3 square miles. Completed in 1968, the structure is well into its service life at over 50 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 fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. An emergency action plan is in place for this dam. The most recent inspection on record was 07/02/2020.
At 47 feet, this dam is taller than 92% 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 Pennsylvania 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 | Pennsylvania |
| County | Montgomery |
| River/Stream | Sawmill Run |
| Coordinates | 40.12028, -75.32806 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 47 ft |
| Dam Height | 47 ft |
| Dam Length | 1,335 ft |
| Year Completed | 1968 (58 years old) |
Storage & Hydraulics
| NID Storage | 740 acre-ft |
| Max Storage | 740 acre-ft |
| Drainage Area | 3 sq mi |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | BOROUGH OF NORRISTOWN |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 07/02/2020 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | PA00324 |
| Federal ID | PA00324 |
| More Info | State Dam Safety Program |