City settles on flood fixes to protect condos, water plant

After a year of study, the Port Washington Board of Public Works agreed to take two steps to reduce flooding on Lake Street during major rainfalls that has swamped the Lighthouse Condominiums and threatened the city’s water plant.

The board agreed to install a trash rack that would stop debris that floats down Valley Creek from clogging a culvert leading to the lake — a problem that has led to some of the past flooding issues in the area.

The board also authorized City Engineer Rob Vanden Noven to design changes to Lake Street that would help block the flow of floodwater to the condominiums and water plant and to hire Stantec to design complementary improvements to the swale through Veterans Park that leads to the lake.

The board is expected to review Stantec’s proposals for the work in January.

The move should please the residents of the Lighthouse Condominiums. Condo Association President Greg Loebbaka petitioned the Common Council to ensure that the trash rack be installed, calling it a vital part of their effort to ensure the building doesn’t flood again.

The association has spent about $54,000 this year on flood mitigation efforts, he noted, telling the board Tuesday, “We’ve demonstrated our commitment. We’re here to hear good news from you, hopefully.”

The cost of the trash rack was estimated by Stantec to be $50,000 to $60,000, although Street Commissioner J.D. Hoile said the city crew may be able to construct the rack, lowering the cost.

The cost of the Lake Street changes is estimated at $211,000.

Those changes include raising the level of Lake Street about three feet at a spot just north of the water plants and the north entrance to the condos, which would form a barrier so floodwaters could not flow south on Lake Street.

It would also involve scraping out six to 12 inches of the existing swale so it could accommodate the rise in water behind the barrier.

That should prevent a flood during 100 and 500-year storms, storms similar to those that have flooded the high-rise and come close to engulfing the water plant, Rick Klein of Stantec told the board.

Four other options were studied, all of which proved to be more expensive than this plan, Klein said. 

Two of the options called for installing a second culvert next to the existing 6-by-7-foot culvert. One would install a 6-by-6-foot culvert, which would handle a 100-year storm but not the 500-year event, and the other called for a 12-by-6-foot culvert to be added, which would effectively deal with both storms.

The cost of these options was $827,000 and $1.2 million, respectively, Klein said.

The other options called for opening the east end of the existing culvert to create a natural stream. Opening 200 feet of stream would cost $534,000 while replacing the existing culvert with an arch culvert and opening 200 feet of stream to create a fish-passable channel along the entire path to the lake would cost $1.8 million.

In the first option, Klein said, “the 100-year water surface is better behaved” while the 500-year storm “is still a little problematic.” The second option, he said, “is quite a nice alternative for both.”

All of the options call for having a trash rack installed, Klein said, but that is not included in the price.

Ald. Pat Tearney, a board member,  noted that the Lake Street option “really does the best job of protecting the water filtration plant and the Lighthouse Condos at the least cost.”

Ald. John Sigwart, a member of the board, favored the Lake Street option but said he is concerned about the potential impact on Inventors BrewPub. 

The owner of the building may have to do some floodproofing to prevent issues there, he noted.

But Ald. Mike Gasper, a member of both the board and the Parks and Recreation Board, noted that the parks board liked the idea of opening up the stream, which could not only help with the floodwaters but also create an amenity that could potentially be paid for in part through grant money.

Sigwart made the motion to do the Lake Street work, noting that if the city wants to open the channel it can do so at a later date.

Board member Phil Bruno questioned if the city should do anything in the area.

“This last storm we had, everything worked out,” he said, referring to an October storm when the culvert was unblocked and water flowed as expected.

“We’re talking about spending a fortune,” Bruno said. “The trash rack is something we have to do, but I have a problem spending this much  money.”

City Administrator Mark Grams concurred, suggesting the city install the trash rack to ensure the culvert remains open so water can flow freely.

“Let’s put that in as a starter,” he said. “Then let’s play it by ear and see what happens.”

But Water Supt. Leo Duffrin expressed concern about that, saying, “If we don’t protect (the water plant), the whole city is going to be upset.”

In past flooding events, he noted, water has gotten into the plant and come close to shutting it down but crews were able to handle the problem before anything significant occurred.