LEBANON, N.H. – The brook behind Pam Green’s home turned into “a tidal wave,” the water was knee-deep in her backyard and the rainfall created “a beautiful little waterfall we never had before,” she said Wednesday, a day after flash flooding washed out roads and prompted evacuations in New Hampshire.

The city of Lebanon received nearly 2 inches of rain in just 45 minutes Tuesday.

“I’ve lived here my entire life and I’ve never seen this amount of water,” said Green, 54, who had cantaloupe-sized rocks pushed into her front yard by the floodwaters.

Gov. Maggie Hassan declared a state of emergency on Wednesday after flash flooding washed out a number of roads and covered others with mud. There were no reports of injuries.

Hassan said the state received nearly 4 inches of rain in 24 hours and the ground was saturated. State and municipal roads alike were affected, especially in the western part of the state.

About 100 yards from Green’s home, flash flooding carved a gash 40 feet long, 25 feet wide and 25 feet deep on state Route 120, a main connector between Lebanon and Claremont.

Erosion caused by heavy run-off led to a water main burst, leaving about 100 homes without water.

Residents of Slayton Hill Road lost power after a wave of water rolled down the steep street — taking out driveways and some power lines along the way. At the bottom of the road was a mound of dirt higher than a house.

“I guess this is what you’d call our ‘Little Irene,”‘ said Tim White, who lives on the street, recalling the August 2011 tropical storm that caused flooding in parts of Lebanon.

“I’m probably one of the more fortunate ones,” said White, who lives at the top of the hill. “Everyone down from us is landlocked.”

At the bottom of Slayton Hill Road sits the Rivermere affordable-housing apartment complex that had its ribbon- cutting ceremony last week and was rendered uninhabitable by the torrential downpours. Residents were evacuated Tuesday from the 17 units that were already rented.

Rivermere was developed by the Twin Pines Housing Trust. Its executive director, Andrew Winter, was shoveling a culvert Tuesday to drain off standing water when he watched the river of water gush down Slayton Hill Road — aided by a blocked culvert uphill — and wash through Rivermere.

“There’s just such a sense of helplessness when you see a wall of water rolling down a hill and there’s no way to stop it,” Winter said.

“It is emotionally devastating.”

Some residents had to be evacuated, gripping a rope slung overhead and across Slayton Hill Road as firefighters guided them through mud and rushing water.

Winter estimates the damage will exceed half a million dollars.