Next month will mark a year since the city pumped 48 million gallons of raw sewage into the Ala Wai Canal after a major sewer line ruptured in Waikiki. To prevent that from happening again, the city has spent an estimated $38 million to put in an emergency repair as well as begin a permanent fix.

City officials yesterday said the project is taking a little longer than expected but remains under budget. City design and construction deputy director Craig Nishimura said the city had hoped to complete temporary lines under Kai'olu Street — where the line cracked on March 24 — by the end of January.

But he said the project was changed to make the work digging under the canal a part of the permanent solution. The city had budgeted a total of $50 million for the temporary work and a permanent fix, he said.

However, Nishimura said the city already completed a temporary bypass line — that big black pipe running along the Ala Wai — which would allow the city to pump sewage out of Waikiki into sewer lines that lead to a treatment plant, rather than into the canal.

So in the event of a problem, the city says it is better prepared than it was a year ago.

"If we run into trouble, we have the bypass," Nishimura said.

That spill was the largest recorded in the state's history. The spill closed some of Waikiki's most famous beaches to swimmers, surfers and canoe paddlers and prompted public health and safety worries.

The city has yet to receive word from the federal Environmental Protection Agency on what fines and sanctions will result from that spill.

In Hawai'i, EPA spokesman Dean Higuchi said he doesn't know when a settlement will be reached.

"Both sides are trying to work out a settlement that will benefit and improve the city's wastewater system," Higuchi said. "Obviously there may be fines levied but the real goal is to make sure this doesn't happen again."

Yesterday , crews from Frank Collucio Construction got ready to begin a critical phase in the bypass project — microtunneling under the canal.

That involves lifting a million-dollar 11-ton "mole" into the 40-foot deep pit behind Ala Wai Elementary School in preparation for the drilling machine to bore 1,200 feet to the other side of the tunnel, near the Beachwalk sewage pumping station off Kai'olu Street.

Company vice president Franco Collucio said the mole will start boring this week at a rate of about four to five feet an hour and keep working to complete the tunnel in about three weeks. The city will then build a 36-inch sewer pipe in the 48-inch tunnel.

Creighton Chang of contractor Hawaiian Dredging said that first pipe could be completed by the end of March. Then the team will bore a second tunnel nearby for a second 36-inch pipe.

Nishimura said design work is continuing on a permanent fix to replace the aging sewer line that broke.

He said the two lines will give the city an emergency backup in the event one line breaks and it will allow more flexibility for maintaining the line.

Reach Robbie Dingeman at rdingeman@honoluluadvertiser.com.