Olympia will see 16-foot tides next week. Is the city ready after last year’s flooding?
The city of Olympia is letting residents know to be prepared for extremely high tides in the downtown area for most of next week. The National Oceanic and Atmospheric Administration predictions show that there will be tides up to nearly 16 feet from February 20 through February 23.
Just over a year ago on January 7, a tide that was predicted to be just over 16 feet caused extensive flooding in downtown Olympia. Runoff from heavy flooding at the Deschutes River in Heritage Park met with a 17.9 foot tide at Budd Inlet, flooding the park.
Photos from the time show the downtown marina, park and some area buildings on the verge of being flooded.
The city has been preparing for sea level rise with its long-term plans for years. The city’s Sea Level Rise Response Plan details the vulnerabilities of the downtown area, and notes that: “Downtown flooding is anticipated to become more frequent and severe in the future.”
The project area starts at Union Avenue downtown and extends north along the length of East Bay Drive until San Francisco Street. The city is working with the Port of Olympia and the LOTT Clean Water Alliance on the project.
How often does downtown Olympia flood?
Downtown Olympia experiences tidal flooding on an average of one to two times per year, according to the Thurston Regional Planning Council’s 2017 flood hazard profile. As sea levels rise in the latter part of the 21st century, the occurrences will increase drastically.
Currently, Olympia experiences daily tide heights of around 14 to 15 feet, according to the Sea Level Rise Response Plan. The floods along Olympia’s downtown peninsula are caused by a combination of factors, including high astronomical tides, storm surges, Pacific Ocean basin phenomena and local wind and wave activity.
Flooding subsides as tides recede. Floods are generally short and last one to two hours. But as sea levels continue to rise, more areas will become at risk of tidal flooding.
Olympia’s response plan utilizes data from the National Research Council to determine how much sea levels around the city will rise in the coming decades. Here’s how the environment will change:
2030: In less than 10 years, sea levels will likely have increased by 5 to 7 inches.
2050: Around the mid-21st century, water will have risen from 11 to 13 inches — or by an entire foot.
2100: When the 22nd century arrives, water levels will likely have increased anywhere from 32 to 36 inches, but could expand as high as 68 inches – or more than 5 feet.
These metrics take into account the fact that Olympia’s ground is subsiding at a rate of about 1-2 millimeters per year, or between 0.4 and 0.8 inches a decade. The city has released an interactive tool that shows how sea level rise will affect Olympia.
Will any stores, roads parking be closed?
Some parts of Olympia are more prone to flooding than others. This includes properties on the Port of Olympia and near the city’s waterfront. Other parts of town, such as along 4th and 5th Avenues near Capitol Lake and Budd Inlet, may experience nuisance flooding at around 17-foot tides.
Tides don’t start to impact the city until they reach around 18 feet high, said Jesse Barham, interim water resources director with the city of Olympia in an interview. For that reason, Barham said the city doesn’t expect roads, parking spots and businesses to be affected, but residents should still remain cautious.
“People should be prepared there will be potential on those days,” Barham said.
In December, The Olympian reported on road closures along 4th Avenue, Water Street, Columbia Street and State Avenue, near Capitol Lake and Heritage Park. Residents may expect parts of these roadways to be closed next week. However, these impacts stemmed from an 18-foot tide, Barham said.
Preparing at home and on the road
If you’re concerned whether your place of residence will be impacted by flooding, the city has a few tips to ensure you stay safe and how to traverse the roads.
Raise items off the floor, especially in lower-level floors like a basement. Do the same for any electronic equipment and make sure they’re unplugged.
If you need to pump out water from your basement, never use a pump or generator that runs on gasoline, It produces toxic carbon monoxide fumes.
Don’t drive or park in flooded areas, and don’t drive around barricades.
If you must drive through water, do it slowly. If flooding reaches around 6 inches high, it will likely reach the bottom of your vehicle. This can cause loss of control or stalling. If your vehicle stalls, restarting it can cause irreparable damage to its engine.
Check your brakes on a clear road if you waded through water that reached a vehicle’s wheel rims or higher. If your brakes are wet, dry them by pressing gently on the brake pedal with one foot as you slowly move with the other foot on the ignition.
This story was originally published February 18, 2023 at 5:00 AM.
