12 'High Hazard' CT Dams In 'Poor' Condition: AP Report

CONNECTICUT — More than 1,500 dams across the United States are in poor condition and increasingly at risk of failing as climate change brings heavier rainfall. What's more, many are in populated areas where, should they fail, at least one person would likely die.

In Connecticut alone, 12 dams fit that description, according to new data uncovered as part of a two-year investigation by The Associated Press. The state does have a history of dam failures, but no one has died in several decades.

Connecticut law allows the state to step in and repair dams if they pose an imminent threat to public safety.

"We take the safety of our residents seriously and that includes ensuring dams are regularly inspected and that issues are addressed in a timely manner," said DEEP spokeswoman Kristina Rozek. "The state does not have any dams with an 'unsatisfactory' condition rating - which means a dam requires immediate or emergency corrective action."

Some 156,000 people live in areas immediately downstream from "high-hazard" dams —meaning those whose failure could mean the loss of at least one life, according to the state’s 2019 Hazard Mitigation report. There are more than 280 such dams in Connecticut and 92 of them are in satisfactory condition, another 42 are in fair condition and the rest don't have ratings or data wasn't available, according to the AP.

The following 12 "high-hazard" dams were listed in poor condition when last inspected, according to AP’s findings:

• Acme Pond Dam in Dayville
• Crystal Lake Dam in Middletown
• Fitchville Pond Dam in Bozrah
• Freshwater Pond Dam in Enfield
• Great Hill Reservoir Dam in Seymour
• Hanover Reservoir Dam in Baltic
• North Grosvenordale Dam in North Grosvenordale
• Oxoboxo Lake Dam in Oakdale
• Silvia’s Lower Pond Dam in Stonington
• Staffordville Reservoir Dam in Stafford Springs
• Sylvia’s Upper Pond Dam in Stonington
• Williams Pond Dam in Lebanon

History of Connecticut Dam Failures

Connecticut has had 24 documented dam failures since 1877, with property damage costing $4.78 million, according to federal dam safety data. The state's hazard mitigation plan says the actual number is higher, however, because flood records are not available from 1938 to 1955 and federal data doesn’t include a number of incidents from 2005.

Fourteen dams completely or partly failed in Hartford and Tolland counties in October 2005 after flood flows exceeded a 100-year event. Another 30 dams were damaged throughout the state.

One of the worst dam incidents in Connecticut history happened in March 1963, when the Spaulding Pond Dam in Norwich failed; six people were killed and there was $6 million in property damage. Crystal Lake Dam in Middletown burst in April 1961, injuring three people and causing $600,000 in damages.

Connecticut experienced a massive rainstorm on June 5 and 6, 1982, that dumped up to 18 inches of rain. Seventeen dams failed during that storm and another 31 were seriously damaged

How Connecticut Regulates Dam Safety

The Connecticut Department of Energy and Environmental Protection oversees the Connecticut Dam Safety Program. The state keeps an inventory of 4,800 dams, 3,088 of which are registered with DEEP, according to the hazard mitigation plan.

"High-hazard" dams are inspected every two years and "significant-hazard" dams — those whose failure would bring property damage but not necessarily loss of life — are inspected every five years.

The Dam Safety Program applies to all dams that aren’t already regulated federally or locally.
Dams found to be unsafe must be repaired at the owner’s expense. If a dam owner fails to rectify the unsafe situation, the state can refer the matter to the state attorney general’s office for enforcement. As a last resort, the state can remove or correct an unsafe dam at the owner’s expense if it presents a clear and present danger to public safety.

The state’s latest emergency operations report also notes that climate change is causing more frequent heavy rainstorms in the spring and in hotter and drier summers. Some dams aren’t built to withstand frequent heavy rainstorms, according to the hazard mitigation report.

"It is true that climate change will come with more frequent and intense weather events which makes it all the more important that dams are designed, inspected and maintained appropriately," Rozek said.

Crystal Lake Dam in Middletown was last inspected in October 2016 and was determined to be in poor condition. It is 140 feet long and 50 feet tall.

A dam was first built on the site in the mid-1800’s for use with a mill, but it failed catastrophically in April 1961. Three people were injured, several roads and a bridge were washed out and some homes were damaged. The state assumed ownership in 1965 and rebuilt the dam a year later. It was repaired in 1990.

The latest inspection report notes that the downstream slope is in poor condition. While it doesn’t show signs of instability, it is covered by small trees and other brush.

Inspectors suggested that the state make several upgrades, including raising the embankment crest and extending the downstream embankment.

DEEP is working on a project to improve the Crystal Lake Dam, Rozek said.

Aging Dams Across Country

Connecticut is one of many states with aging dams in need of repair.

On average, the nation’s dams are more than 50 years old. In some cases, they weren't designed to handle the amount of water that could result from the increasingly intense rainstorms of a changing climate. Rising temperatures will "intensify the Earth’s water cycle" and increase evaporation, according to NASA. That increased evaporation will bring more storms and more rain to many areas, as well as an increased risk of flooding.

Despite the risks and need for repairs, little information has been publicly available about dam conditions, the AP found. Since 2002, the U.S. Army Corps of Engineers has redacted inspectors' condition assessments from its National Inventory of Dams citing security concerns. Only the hazard rating of some dams are publicly available, which determine the likelihood of human death or economic and property loss in the event of a catastrophic failure.

The AP analysis was based on data obtained through dozens of state open-records requests, which allowed it to create a dataset containing both hazard levels and condition ratings for dams across 45 states and Puerto Rico. Five states – Alabama, Illinois, Maryland, New Jersey and Texas – did not fully comply with the records request. Iowa provided all requested documents but had no dams listed as both high hazard and in poor or unsatisfactory condition.

Inspection reports also revealed a litany of problems. Some dams leaked, indicating internal failure. Others showed erosion, potentially destabilizing extensive tree growth or even holes from burrowing animals. In some cases, spillways were flagged because they aren't big enough to handle increased rainfall.

The AP data also showed yearly budget and staffing levels for dam safety offices in each state. Connecticut has budgeted $750,000 every year for dam safety since at least fiscal year 2011.
Georgia had the most high-hazard dams in poor or unsatisfactory condition at 198. North Carolina was second with 168, followed by Pennsylvania at 145, Mississippi with 132, Ohio with 124 and South Carolina with 109.

Patch editor Dan Hampton contributed to this report