Posted on 01 August 2012 by Keith Lacey
Building huge catch basins to capture massive amounts of water that fall during heavy rainstorms has successfully stopped flooding in other parts of town and installing more along Main Street is likely the only long-term solution to solving serious flooding problems in the downtown area around 85 Street and 74 Avenue, says Town of Osoyoos engineering consultant Terry Underwood.
During a special meeting of town council this past Thursday, Underwood, who works for the engineering company True Consulting Group out of Kelowna, said this low part of the downtown core has been having problems with excess water for as long as he’s been doing consulting work for the Town of Osoyoos dating back to 1974.
Two major rainstorms on June 30 and July 20, both which dumped more than 25 millimetres of rain across Osoyoos, were two of the heaviest storms in this town’s history over the past 25 years, said Underwood.
Both storms resulted in heavy flooding near the area of 85 Street and 74 Avenue. Neighbours Sonja Domene, who owns Manuel’s Tiles, and Brent Ross, who owns 85 Street Boutique, complained publicly about how the flooding caused during the two recent storms resulted in far more flooding than before road construction upgrades in the area were completed over the past nine months.
Underwood confirmed the flooding problems in the area during the last two storms were exacerbated by the fact newly-installed pumps at a nearby lift station were not working properly and informed council how the electrical contractor responsible for installing the pumps was not co-operative when ordered by True Consulting and town staff to get the pumps operational as quickly as possible.
The town’s philosophy when dealing with water control caused by rainfall over the past 20 years has been “slow it, spread it and sink it,” said Underwood.
Because there are so many low areas in town, the town has installed numerous dry wells for over two decades, but the system wasn’t designed to handle massive amounts of storm water, he said.
Mayor Stu Wells said global warming and climate change have resulted in more and more “intense weather events”, where Mother Nature drops massive amounts of rain in a short period of time and every indication is this is going to happen more often in the future, which causes serious concern of how to handle the situation here in Osoyoos.
“We’re seeing this trend everywhere in the province right now and unfortunately it’s caused by global warming and climate change,” said Wells.
Underwood agreed, saying there have only been three storms in the past 10 years recorded by Environment Canada that had more than 25 mm of rain fall during one storm and two of them happened over three weeks in the past month.
To have two major storms so close together is very unusual and records indicate that hasn’t happened before at any time in the previous 35 years, said Underwood.
One option to control flooding in the 85 Street and 74 Avenue corridor is to “build more dry wells and pipes in order to build capacity”, but this isn’t an affordable or reasonable solution considering massive infrastructure improvement would not have been able to handle the amount of rain that fell during these two recent episodes, said Underwood.
There are already 13 small catch basins and five dry wells in this area of town, he said.
“Dry wells don’t respond well to intense events like we had on June 30 and July 20,” said Underwood.” If this amount had fallen over two hours or three hours or six hours, I don’t think we would have had a drop down there (dry wells) … but we had a river of water in 20 minutes.”
During both storms, massive amounts of rain found their way down from Highway 97, down Main Street, and into the 85 Street and 74 Avenue corridor, he said.
The best option is to control water at the top end of the system near the top end of Main Street with huge catch basins, he said.
Similar flooding caused major problems for years near the Safari Beach Resort until four huge catch basins were installed near 89 Street to catch water higher in the system and there hasn’t been a complaint about flooding near Safari Beach in over a decade, he said.
The fact two pumps weren’t working properly certainly didn’t help the situation during either storm, said Wells.
“If things had been working like they should have, I don’t know if we’d be here today talking about this,” he said. “One pump wasn’t wired and the second kept limiting out.”
Underwood said he has become “completely frustrated” with the electrical contractor hired to hook up these pumps as he was told repeatedly to finish the job and wouldn’t listen.
“The electrical contractor has been very frustrating to deal with,” he said. “You’re going to have to make a decision about this individual’s being able to work for the town again … he was told by our staff and by town staff” and didn’t respond, said Underwood.
Both new pumps feature 7.5 horsepower motors, but impellers for 10 horsepower motors were installed, resulting in the one pump constantly shorting out, he said.
The motors have finally been tested and are working properly and would be able to pump out large volumes of water should a major storm happen tomorrow, he said.
Wells said he feels sorry for the property owners who have been most adversely affected by the flooding.
“I don’t think the people down there can take much more mentally,” he said. “They are battle scarred, they are worn out and they are fearful.”
Underwood reiterated handling major amounts of water further upstream before massive amounts accumulate in this area is the best long-term solution.
“My observation is we’re going to have to deal with Main Street … and get water off Main Street … it’s the problem,” he said.
Property owners in the area have complained recent road construction along 85 Street was supposed to alleviate some of the flooding issues, but have resulted in worse flooding than ever.
Underwood said staff he’s talked to say the road level might be up an inch or two at the most and this would not have made a significant difference during either flood considering how much rain fell.
Ross was given the opportunity to speak to council and said his biggest issue is flooding is worse since construction was completed.
“It’s real simple,” he said. “It’s broke so fix it.”
The road construction project has resulted in much more severe flooding and that’s not acceptable. The fact pumps weren’t working properly during two major storms is also unacceptable, he said. The fact town council is discussing this issue and considering projects to help alleviate the problem is appreciated, said Ross.
Underwood said he will work with town administration to complete a report recommending huge catch basins be installed on or near Main Street before returning to council.
Wells said there are budget implications involved, but everyone knows it’s important to correct this problem soon and he would like a final report with best options presented as quickly as possible.