Purity Lake Dam

DANFORTH PONDS· Carroll, New Hampshire· Built 1750· Earth· 13 ft tall
High Hazard Recreation Private

Key Takeaway

Purity Lake Dam is classified as high hazard in New Hampshire. It was completed in 1750 and is 276 years old. Its primary use is recreation. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.

Physical Details

Dam Height 13 ft (taller than 36.5% in NH)
Dam Length96 ft
Dam TypeEarth
Max Storage182 acre-ft
Normal Storage162 acre-ft
Surface Area27 acres
Drainage Area7 sq mi
Max Discharge240 cfs
Year Completed1750 (276 years old)
Year Modified1944
NID IDNH00284

Safety Information

High Hazard

Loss of human life is likely if the dam fails.

Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?

Emergency Action Plan: Yes
Last Inspection: September 26, 2022
State Regulated: Yes
Regulatory Agency: NH DES

Ownership

PURITY SPRING RESORT ANDNH AUDDUBON

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Purity Lake Dam?

Purity Lake Dam is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Purity Lake Dam?

Purity Lake Dam is owned by PURITY SPRING RESORT ANDNH AUDDUBON (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Purity Lake Dam built?

Purity Lake Dam was completed in 1750, making it 276 years old. Many U.S. dams were built between the 1930s and 1970s during a period of major infrastructure investment.

What is the primary purpose of Purity Lake Dam?

Purity Lake Dam serves the following purposes: Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Purity Lake Dam?

Purity Lake Dam has a dam height of 13 ft. Dam height is measured from the natural streambed at the downstream toe to the top of the dam, and may differ from the visible height.

When was Purity Lake Dam last inspected?

Purity Lake Dam was last inspected on September 26, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.

Data from the National Inventory of Dams (NID) maintained by the US Army Corps of Engineers. Dam conditions may have changed since the last update. This site is not affiliated with USACE. Do not use for emergency planning — contact your local dam safety program.