Dry Creek flood mitigation close to complete

Third avenue: | Port Alberni will complete $2 million worth of flood protection and salmon enhancement work in mid-October.

The former Jade Restaurant was demolished on Aug. 29 to make way for the city’s Dry Creek flood mitigation work.

The work to protect lower Third Avenue from winter flooding is three-quarters of the way complete, according to city engineer Guy Cicon. The contract was award to Bowerman Excavating Ltd. earlier this year.

The Jade Restaurant, which the city purchased in July, was demolished on Aug. 29, making way for a new box culvert to be installed underneath the Restaurant Bridge at Third Avenue.

“That increases the cross-sectional area of the bridge to allow more flow to go through,” said Cicon.

“If you didn’t have that then you’d have a restriction. We have to increase the area to improve the flow.”

The restricted flow under the Restaurant Bridge (which was located beside the Jade) is part of the reason behind the repeated flooding of Third Avenue, Cicon said.

“That flow restriction is one of the causes of the flooding.”

Channel improvements along the entire length of Dry Creek, which flows underneath Restaurant Bridge, will deal with the other causes of the flooding.

“We’re doing channel improvements to improve the flow,” said Cicon.

This work also extends behind Smitty’s on the opposite side of Third Avenue and all the way back to approximately Bute Street.

“The existing channel cross-section isn’t big enough either so we’re enlarging the downstream channel.”

The width of the channel will increase from six to seven metres previously to 12 metres once construction is complete.

“It’s nearly doubling it.”

Widening the channel will include steepening the banks.

“We’re using gabion baskets so that allows steeper banks and more cross-sectional flow,” Cicon said.

Gabion baskets are riprap covered in wire or metal and designed to decrease erosion of stream banks.

It’s not just Port Alberni’s human residents that will benefit from the flood mitigation.

“We’re digging fish habitat pools,” said Cicon.

“They’re being installed upstream of Fourth Avenue [inside Dry Creek Park]  for salmon habitat enhancement.”

The work is being supported by West Coast Aquatic.

According to Cicon, no modification of Dry Creek could be done without considering the salmon.

“You can’t do one without the other,” he added.

“A stream is inherently linked to the environment… engineering the flood protection isn’t independent of everything else. They go hand in hand.”

The grant funding that the city received (one-third each from the provincial and federal governments) required the city to show an environmental benefit as well.

“A project like this with grant funding must demonstrate an improvement to the environment,” Cicon said.

As part of that, there’s a low flow channel being carved into the bottom of the creek bed.

“It’s a carved ditch in the bottom of the ditch,” said Cicon.

“In very low flows, water is concentrated in a low flow channel so that fish can more easily move from one habitat pool to the other.”

A wider channel on the other hand means low water levels.

“If it was just a 12-metre wide  bottom, the water would be really shallow.”

The low flow channel will be about one metre in width, Cicon added.

One of the problems encountered with this summer’s drought  was fish pools drying up in city creeks. Sheena Falconer from West Coast Aquatic spent part of her summer relocating fish because of low flows. The low flow channel is designed to help alleviate this situation in future years.

Along with the salmon enhancement work, they will also do some general environmental restoration of Dry Creek’s banks.

“We’ll be doing  some restoration  work as well, including planting native vegetation like cedar, fir and salal,” Cicon said.

“It’s all about combining flood improvements with habitat improvements.”

The work should be completed by mid-October, before the winter storms and flooding it’s designed to mitigate.

Cicon hopes that the work to improve the creek’s flow will eliminate the

flooding that has plagued lower Third Avenue.

“The amount of water won’t change, it’s just how we’re managing that water.”

reporter@albernivalleynews.com

twitter.com/AlberniNews

Just Posted

Port Alberni RCMP identify suspect in locker room thefts

Multiple complaints came in about thefts from Echo Centre lockers

Logging truck accident briefly closes Franklin River Road near Port Alberni

A single vehicle rollover involving a logging truck temporarily closed Franklin River… Continue reading

Sports shorts: camps for kids, BC lawn bowling finals in Port Alberni

Lawn bowling BCs Port Alberni Lawn Bowling Club will host the provincial… Continue reading

Set wizards make it happen at Mainstage Festival in Port Alberni

Eight plays in eight nights means turnover timelines are tight

Diary of Anne Frank, Cherry Docs dominate Mainstage 2019 awards

Annual theatre competition wraps up in Port Alberni

Joaquin ‘El Chapo’ Guzman sentenced to life in prison

Experts say he will likely wind up at the federal government’s Supermax prison in Florence, Colorado

Olympic softball qualifier gets $150K boost from provincial government

2019 Americas Qualifier to be held in Surrey from Aug. 25-Sept. 1

Gas price inquiry questions Trans Mountain capacity, company denies collusion

The first of up to four days of oral hearings in the inquiry continue in Vancouver

‘Benzos’ and fentanyl a deadly cocktail causing a growing concern on B.C. streets

Overdoses caused by benzodiazepines can’t be reversed with opioid-overdose antidote naloxone

Chinook retention begins on North Island, but amid new size limit

DFO calls measures ‘difficult but necessary’ following rockslide on Fraser River

Will you be celebrating national hotdog day with any of these crazy flavours?

The popularity of hotdogs spans generations, cultures

Former home of accused Penticton shooter vandalized

Ex-wife of man who is accused of murdering four people had her house vandalized

Injured humpback returns to waters near Comox a year later

Photographer spotted Ocular near Comox again and noticed the whale has been healing

Survivor of near-drowning in B.C. lake viewing life through new eyes

“If I died that day, the baby wouldn’t know his dad,” said 31-year-old Mariano Santander-Melo.

Most Read