Feb. 17 5:00 p.m. update:

The city plans to begin pumping water as early as tomorrow afternoon. On Friday, the city will test run the pump for 10 hours, and plans to run the pump 24/7 Feb. 22 – 26.

The Public Works department also improved the makeshift walkway some residents were using to get around the flood. The walkway is now wider with a retaining wall separating people from the walkway’s edge.

Feb. 16 12:00 p.m. update:

The city plans to start pumping water out of the basin this week, said John Woodcock, the city’s chief engineer.

Original Post:

The city of Bonney Lake is scrambling to solve a flooding problem thought to have been solved 20 years ago.

What started as a few inches of water on 62nd Street behind Lakeridge Middle School at the end of December turned into a full-on flood by February, submerging 17.5 acres of forest land and roads and impacting residents in the area.

The water has become so deep that vehicle access to 62nd street, 185th street, 187th street and the intersection of 188th and 62nd has become difficult, if not downright impossible.

“At last measurement, the water across 62nd street was approximately 40 inches above road level,” said Senior Planner Jason Sullivan at a special council meeting devoted to discussing the flooding Feb. 5.

The water comes over a bridge built on 62nd. The bridge is now totally submerged, guardrails and all.

The city also measured the water to be between 2.5 and 3 feet deep at the intersection of 188th and 62nd and 187th street.

Cars were still able to get across 185th since last Wednesday, but residents expressed concern about how long that will last.

“We lost Internet and phone service over the weekend. Mail service stopped two weeks ago,” said Sarah Howell, who gets around the water with the help of a small dirt ledge and some rope. She often does this with her five year old daughter. “We are slowly being cut off from the city we are living in.”

Perry Purdin, another resident, was wading through the water until it became too high even to do that. He bought a boat so he could get across the 300 foot flooded section of the road.

Purdin’s problems don’t stop there; the water prevents emergency vehicles from getting to his house. East Pierce Fire and Rescue have hooked up a hose to a nearby hydrant, and the hose leads up to his home so firefighters have access to water in case of fire.

Howell, Purdin and other residents affected by the flood said they started mentioning the water issue to the city near the end of December when access to their homes starting becoming difficult.

The reason the city did not act until February was because the water in the basin has always infiltrated back into the ground before it became a problem, said John Woodcock, the city’s chief engineer.

“It’s been 20 years since this thing has run over the roads and did something crazy,” he said.

The last time the basin flooded was in 1996, when a Pineapple Express (cold weather followed by warm moisture) came through the state, bringing a snowstorm then heavy rain. This caused the snow to melt more quickly than the ground could absorb it and the basin flooded, Woodcock explained. When the rain stopped, the water eventually went back into the ground. The city went in a year later and raised the road to keep the road from flooding again.

“It always goes into the ground. Always has in the past,” Woodcock said. “There was nothing in the past that suggested this water was not going into the ground.”

After the City Council met and discussed the issue, the city held an open house for the residents affected by the water to talk with the council Feb. 8.

Unknown cause

According to the city, the water is not caused by a leaking water main, so fingers are pointing to both heavy rainfall and the natural springs in the area.

The city collected NOAA Tacoma station data that shows it rained 33.8 inches in October 2015 to January 2016, which is considered the rainy season in western Washington.

This would make the 2015-2016 rainy season the second wettest in 20 years, drowned out by the 35.3 inches that fell in 2006.

The McMillin Reservoir in South Hill confirmed its own measurement of 32.09 inches of rain from Oct. 2015 to Jan. 2016.

NOAA also measures rainfall at the reservoir, but they measured only 17.31 inches of rain during the same time period, a disparity Nora Doyle, a spokeswoman for Tacoma Public Utilities, could not explain.

But the possibility of exceptionally high rain fall doesn’t answer all the questions.

“The last 20 years, we’ve had rain. But it didn’t do this,” Woodcock said. “There may have had water in the basin but it didn’t do this… to not be above the roads, and now all of a sudden to be so dramatically above the roads, that’s what is puzzling.”

Another source of water are the natural springs in the area, which add water to the basin even when it’s not raining.

But this answer also has issues. Residents in the area say they’ve known about the natural springs for a while, some for as long as 17 years, and while water collecting on the side of the 62nd street bridge was common in the winter, the water rarely came onto the road, and never in these amounts.

The city said it does not know whether or not another source of water is adding to the problem or where the source of the natural springs are, which means the springs may or may not be putting more water than usual into the basin.

And while the source of the water is definitely an issue, Woodcock said, a bigger problem is that the water isn’t dissipating back into the ground like it used to.

“We are not sure if the basin is converting over into a lake environment or if there is something else that is preventing the water from infiltrating into the ground,” Woodcock said. “Maybe water is already down there, so it’s full, and it’s going to take a long time to move out.”

But again, these theories have the holes Woodcock wishes the flood basin had.

“Why didn’t it do this last year, or the year before that?” Woodcock continued. “What has happened this year that hasn’t happened in the past? That’s what we are scratching our heads over.”

Short and long-term solutions

Mayor Neil Johnson asked the city to pursue pumping the water out of the basin at the beginning of last week, and it seems to be the best short-term solution the city has at the moment.

Woodcock said the city has permission from a couple of residents to use their property to set up the pump and pipes. Cascade Water Alliance and Washington’s Department of Ecology have given the green light for the city to pump water into Lake Tapps.

By press deadline, all Woodcock is waiting for is the city’s final thumbs up.

The city has estimated that every foot of water in the 17.5 acre area is about 6 million gallons, and the pump the city has can move close to 1,000 gallons a minute.

“I haven’t done all the math yet on this thing, but its going to take several weeks,” Woodcock said. “But we need to get ahead of this thing.”

In case pumping the water doesn’t help straight away, Woodcock met with a company that may help the city build pedestrian bridges Feb. 12.

The city can’t start executing long-term solutions until the water is clear, but Woodcock said the options the city is considering include raising road levels again, paving new access roads in the area and installing a permanent stormwater pump station that would pump the water away every year before it became another problem.

“But we’re not there yet,” Woodcock said. “We are dealing with the emergency and trying to get ahead of that, and I think we have a solution that can start moving us in that direction.”

This article has been updated to reflect the correct dates for the last rainy season from Oct. 2015 to Jan. 2016.