A second arson attack on reserve bushland along the Waikareao Estuary has Tauranga firefighters worried nearby properties will be put in danger if the fires continue.

Tauranga Fire Brigade was called to the boardwalk, about 250 metres from the Montgomery Road, Judea end, about 10pm on Sunday following multiple calls from members of the public of a large section of wetlands on fire.

Damage to the wetlands along the Waikareao Estuary from last night's fire.

Tauranga Fire Brigade senior station officer Phil Price says two appliances battled the 'well involved” scrub fire for about an hour to ensure nearby houses were not in any danger.

'We had to use a portable pump and had two trucks. The tide was fairly full and we were able to take the pump down and pump water out of the harbour to put the fire out,” says Phil.

'It was starting to spread when we got there to knock it down.”

Phil says the fire, which reached about 200 square metres, did not pose any immediate threat to nearby residents, with the closest house about 50 metres away, but if the wind had got up things it might 'have been a different story”.

The boardwalk fire is the second in three days after a section of the Daisy Hardwick boardwalk was left charred around the edges on Friday night.

Firefighters believe somebody deliberately set fire to some pampas bush near the boardwalk.

'It's a bit concerning about this if someone is lighting these fires. This one would have definitely been suspicious; these fires don't light themselves,” says Phil.

The boardwalk blaze was part of a busy night for the Tauranga crews called out to three vegetation fires between 4pm and 10pm.

Phil says the two other fires, at Tangitu Road in Te Puna and Robins Road, Judea – between 4pm and 5pm – were relatively minor compared to last night's blaze.

'There was a small shelterbelt fire at Te Puna and just one truck put it out. It was a fire on the ground which spread to the shelterbelt; it wasn't a big fire.

'We are not sure how it happened.”