Floods strike thousands of houses in northern Philippines

Floodwaters reaching more than four metres high swamped thousands of houses in the storm-battered northern Philippines on Tuesday after rivers overflowed following heavy rain and a dam release.

Typhoon Man-yi drenched swaths of the Philippines over the weekend, swelling the Cagayan river and tributaries, and forcing the release of water from Magat Dam.

The Cagayan broke its banks, spilling water over already sodden farmland and communities, affecting tens of thousands of people.

Buildings, lamp posts and trees poked through a lake of brown water in Tuguegarao city in Cagayan province where provincial disaster official Ian Valdepenas said floodwaters reached more than four metres in some places.

"We experienced very heavy rains two days ago, but the flood just started to rise when Magat Dam started releasing huge volumes of water," Valdepenas said.

"Plus, our land is already saturated because of the consecutive typhoons hitting the area."

Man-yi was the sixth major storm in a month to strike the Philippines, which have left at least 171 people dead and thousands homeless, as well as wiped out crops and livestock.

About 20 big storms and typhoons hit the Southeast Asian nation or its surrounding waters each year, killing scores of people, but it is rare for multiple such weather events to take place in a small window.

In the neighbouring province of Isabela, Jun Montereal of the Ilagan city disaster preparedness committee said 30,000 people were still affected by flooding.

But the situation was slowly improving.

"The flood is subsiding now little by little, it's slower because the land is already saturated but we are way past the worst," Montereal said.

"We are really hoping that the weather will continue to be fair so the water can go down. I think the water will completely subside in three days," he said.

"I can now see the roofs of houses that I wasn't able to see before because of the floods."