Longlands Hope Sw Pd Dam Reservoir Report
Nearby: Eugene Oliver Dam Knollwood Dam 2
Last Updated: December 15, 2025
Longlands Hope Sw Pd Dam, also known as Knollwood Dam 1, is a private earth dam located in Williamsburg, South Carolina.
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Summary
Completed in 1940, this dam serves primarily for recreational purposes on the TR-Santee River. With a height of 13 feet and a length of 525 feet, the dam has a storage capacity of 55 acre-feet and covers a surface area of 7 acres.
Despite being classified as having a low hazard potential, Longlands Hope Sw Pd Dam is in poor condition as of its last inspection in October 2017. The dam is uncontrolled and has no spillway, which may pose a risk during heavy rainfall events. The risk assessment for this dam is moderate, with a DSAC risk rating of 3, indicating a need for improved management measures to address safety concerns.
As water resource and climate enthusiasts, it is crucial to monitor the condition of Longlands Hope Sw Pd Dam and advocate for necessary repairs and maintenance to ensure the safety of the surrounding community and the sustainability of the recreational activities it supports. Additionally, efforts should be made to enhance emergency preparedness and risk management measures to mitigate potential hazards associated with this aging infrastructure.
Year Completed |
1940 |
Dam Length |
525 |
Dam Height |
13 |
River Or Stream |
TR-SANTEE RIVER |
Primary Dam Type |
Earth |
Surface Area |
7 |
Nid Storage |
55 |
Hazard Potential |
Low |
Foundations |
Unlisted/Unknown |
Nid Height |
13 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Santee River Near Pineville
|
676cfs |
Black River At Kingstree
|
1280cfs |
Lake Moultrie Tailrace Canal At Moncks Corner
|
9370cfs |
Santee River Nr Jamestown
|
1170cfs |
Back River At Dupont Intake Nr Kittredge
|
311cfs |
Lynches River At Effingham
|
558cfs |
Dam Data Reference
Condition Assessment
SatisfactoryNo existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
Fair
No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action. Note: Rare or extreme event is defined by the regulatory agency based on their minimum
Poor A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency. Investigations and studies are necessary.
Unsatisfactory
A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
Not Rated
The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Not Available
Dams for which the condition assessment is restricted to approved government users.
Hazard Potential Classification
HighDams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
Significant
Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environment damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
Low
Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
Undetermined
Dams for which a downstream hazard potential has not been designated or is not provided.
Not Available
Dams for which the downstream hazard potential is restricted to approved government users.
Longlands Hope Sw Pd Dam