Although Tonka’s loss will be deeply felt, family members say the 1981 Ford Courier saved their Palolo house Thursday morning.

“It was a special truck,” said owner Wayne Costa.

The truck was parked where a 16-inch water main broke at about 6 a.m. Thursday, and sank into a sinkhole that opened up at Hinahina Street and 10th Avenue.

It was the third main break the Costas have experienced, and the second in about a year at the same intersection. But their house was spared this time from the kind of major damage it received last year.

“It actually saved our house because all of the rocks were shooting up in the air,” Costa said. “Tonka made it all go the other way — all the mud and water came on our house, but no rocks. Tonka saved our house.”

Another family car, a restored ’67 Corvette that Costa estimated is worth $50,000, “was up to its doors in mud,” he said.

Costa, 73, and his wife, Sala, 65, had finally recovered from the damage incurred in last year’s main break. Grass had just been replanted two weeks ago in their front yard, the final touch in restoring the home.

In last year’s break the concrete driveway was pushed up and had to be replaced, and the house had to be leveled because it sank on two sides, Costa said.

Sala Costa said she was awakened Thursday morning by the sound of ”rumbling of the rocks hitting the bottom of the truck and the water,” adding, “It was spooky.”

Initially, she said, she thought it was a rockslide on the Palolo Valley slopes.

The Board of Water Supply said the force of water from the break caused a sinkhole to open up in the street. The agency got the call at 6:04 a.m.

A troubleshooter arrived at 6:45 a.m. and immediately began the shutdown of the valves, which was completed at 8:30 a.m. A repair crew arrived at 9 a.m. to clear debris and begin repairs.

The repair work was expected to continue into Thursday night.

On Thursday afternoon 19 homes were without water. A temporary bypass restored service to four houses, and a water wagon supplied water to the others.

The waterboard said the 16-inch cast-iron pipe, installed in 1964, “had been identified and scheduled for replacement as part of a Palolo Water System Improvements Part IV project,” scheduled for construction in 2017.

Sala Costa said the rupture created a “geyser” that caused water to flow like a river, creating waves of muddy water. If a contractor hadn’t lifted the house up a few feet after the last break, “we would have been underwater again,” she said.

“It’s frustrating because it happens over and over,” she said. “It’s an old neighborhood. They should look into repairing the whole thing instead of patchwork. … It’s like putting a Band-Aid on the problem.”

Tonka was eventually towed from the hole. It is insured but its fate was uncertain Thursday.

The Board of Water Supply sent out a claims representative with paperwork. Costa said he knows him well.