Hurricane Agnes: The Great Flood of 1972

This is information about the great flood of 1972 caused by Hurricane Agnes and how it affected Onoville Marina Park and the Kinzua Dam.

SMALL IMAGE OF Hurricane Agnes FLOODING MAP - LINK to bigger map (SOURCE: Army Corp of Eng)

A view of Onoville Marina Park on June 25, 1972 with roadside signage

Hurricane Agnes slammed into the Florida panhandle as a Category 1 storm on June 19th, igniting 18 tornadoes and killing 9 people. The storm worked its way up the east coast before returning back to the ocean off the coast of Virginia as a tropical depression on June 21st. Agnes returned back inland on June 22 along the PA-NY border as a tropical storm. The storm brought torrential rainfall to New York, Pennsylvania, Maryland and Virginia before finally disappearing into Canada. Both Southwestern NY and Northwestern PA received fifty consecutive hours of rainfall, with most areas receiving 7 to 12 inches of rain, and some areas receiving upwards of 15 inches. Due to the widespread flooding from Agnes, more than 100 people lost their lives, with an estimated $3.1 billion in damages across 12 states.

Hurricane Agnes Timeline at Onoville Marina Park

This is an account of what happened at Onoville Marina Park during Hurricane Agnes in 1972 from journal entries by Wallace "Dutch" Fenton, the Onoville Marina Manager at that time.

Tuesday, June 20, 1972: 1320ft

Rain begins at about 3 PM - Reservoir is at about 1320 ft elevation.

Wednesday, June 21, 1972: 1340ft

Heavy Rain begins by mid-afternoon. Culvert pipes cannot handle the amount of water and cause washouts in the driveways. Picnic tables in lower picnic area were lashed to trees (Were later underwater for over two weeks), Picnic tables in far picnic area were moved back to what was thought to be above potential flood levels (Floated away later due to flooding). The County boat was used to let out more mooring line to allow the boats to rise with the water level of the reservoir. Mooring lines were checked until midnight. Dock #2 was broke off shore connections due to the high water. Home at 3 AM. Reservoir level was at about 1340 ft.

Thursday, June 22, 1972: ~

Rain continues throughout the day. Back to work at the marina by 7 AM. Throughout the day boats were pumped of water, the dock cable was adjusted and mooring lines were checked. Water levels were near the top of the boat ramp. Home by 11 PM.

Friday, June 23, 1972: ~1341ft

Back to water at the marina by 5:30 AM. About 25 boats on moorings needed more line due to the rising water levels. Some of the smaller boats were towed into vacant dock slips to ease the burden of continuously adding more line. Boats and trailers were then moved out of the Onoville parking lot to the parking lot along side Luce's Store (which was located across from the marina). The work shanty and ticket booth were moved to the high part of the park entrance. Electric was shut off. Water levels were now above the flag pole and heading up into the parking lot. Back home at 10 PM.

Saturday, June 24, 1972: 1350ft

The rain continues throughout the day. Back to work at 7:30 AM. The parking lot was now nearly under water. Several boat owners came to the marina to see if their boats were alright. Vast islands of debris were seen floating in the Reservoir's main channel and would occasionally be swept into the bay when the wind shifted. Hours were spent keeping away the large quantities of sticks and logs from the fiberglass boats. By late Saturday afternoon, the Reservoir level was at about 1350 ft.

Sunday, June 25, 1972: ~

On Sunday there was a constant stream of watchers on the Perimeter Rd to see the docks and the boats in the middle of the bay, instead of on the edge. Boats were pumped out throughout the day. A few winches on the old "Steel-N-Foam" system were getting low on cable, so a 20 to 30 ft piece of cable was clamped onto the existing cable. A couple of locals volunteered to check moorings and add rope. Spare time was spent searching for loose picnic tables (6 picnic tables were losted due to the flooding).

Monday, June 26, 1972: ~1358ft

The rising water levels in the Reservoir had slowed to a point where it was barely noticeable. The clouds finally parted and for the first time since Wednesday, there was sunshine.

Tuesday, June 27, 1972: 1362.17ft

The Reservoir reached peak levels at 5 PM on Tuesday at an elevation of 1362.17 ft.!!! The maximum flood pool for the Allegheny Reservoir is 1365 ft.!!!

Water Elevation at Kinzua Dam June 20-27, 1972

The chart below is the Water Elevation at Kinzua Dam June 20-27, 1972 and shows the following:

  • Summer Pool Water elevation of 1328 ft
  • Kinzua Dam Flood Control Pool Maximum Elevation of 1365 ft
  • Peak Water Elevation on June 27, 1972 of 1362.17 ft

Chart of Water Elevation at Kinzua Dam June 20-27, 1972

Did You Know?

Water Level Surge

The water level of the Allegheny Reservoir rose over 34 feet in one week!

Costs

At the time of the storm, Hurricane Agnes was the costliest disaster in United States history, causing over $3.1 billion in damages. The estimated cost of damages in 2025 would be about $24 billion.

In 1965, the construction of the Kinzua Dam cost approximately $108 million; the Dam prevented over $247 million in damages to downstream areas during Hurricane Agnes. As of 2024, the Dam has prevented over $1.2 billion in damages.

References

 

To view the "Hurricane Agnes: The Great Flood of 1972" kiosk panel that is currently located at Onoville Marina Park, Click Here