Upgrading Meridian Lake Access (on the north)
Those visiting the Meridian Street End public access to Haller Lake over the past year or so may have noticed some changes. In Fall of 2020, Seattle Public Utilities (SPU) began a restoration project to improve the health of Haller Lake [personal communication, Donna Pacanovsky, SPU System Operations Planning and Analysis]. At the end of Meridian Avenue N, just south of N 128th, SPU installed catch basins (CBs) that replaced older, outdated drainage “sandboxes” that had no storage for sediment removal. “The new CBs contain sumps that capture/store sediment rather than transferring it into the lake. They will be inspected annually by SPU and cleaned as needed.” SPU also undertook a major restoration of the area between the end of the street and the lake. Non-native invasive plants were removed, including blackberry bushes and Japanese knotweed. The lake near the shoreline was restored by removing sediment, stabilizing the bank, and strategically placing some logs. According to Ms. Pacanovsky, “The logs have been purposely placed in the lake at the location where the sediment removal work was done in 2020. This was required habitat mitigation for the project per the Washington State Department of Fish & Wildlife.” Finally, in September 2021, after the troublesome invasive plant Japanese knotweed, was removed for the second time, extensive plantings of native plants took place. Access to the lakeshore is to be provided by a 3-foot-wide footpath. The new plantings will be maintained by SPU, who will also perform light cleanup, until approximately September 2022 when responsibility for the area will revert to Seattle Department of Transportation (SDOT). Through SPU, I have formed a Friends of Haller Lake Meridian Street End Volunteer Group, now officially registered with the Adopt-A-Street Program. We will periodically remove nonnative plants and trash from the area, although we do not expect to become active until around September, 2022.
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| The Meridian Street End access in April 2020, when it was overgrown with blackberry bushes and other invasive plants |
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The area after clearing and planting with native plants (October 27, 2021)
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Lake Level Fluctuating
In visiting the Meridian Haller Lake street end over the past year and a half, lowering of the lake’s level became conspicuous. The logs placed by SPU for habitat mitigation help demarcate the changes.
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On February 5, 2021, the lake was quite high; the log in the foreground is almost covered by water
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| By August 25, after a very hot dry spell, the lake had receded so that many logs were completely exposed. John Niemann said that, at the lowest point, the lake was 20 inches lower than normal based on readings at his dock. Several lakeshore residents remarked that they had never before seen the lake so low. |
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On October 27, the lake had come up a few inches but was still low, with those logs still exposed
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| Finally, by November 27, after a lot of rain, the lake was about back to what it had been in February. You can see that the small log in the foreground is at about the same level as in February; another log has floated in behind it. |
Lake's Drainage Basin
When the lake level was extremely low, I contacted Ms. Pacanovsky about the water sources contributing to Haller Lake. According to her SPU sources, “the lake largely collects storm-water runoff from the north, primarily through a system of culverts, ditches, and drainage pipes. One branch of the system is located east of Meridian Ave N and heads south primarily through private properties until discharging to Haller Lake. A second branch, also consisting of culverts, ditches and drainage pipes, also collects flow from the north, including runoff from Ingraham High School, and conveys runoff south primarily within the Meridian Ave N right-of-way until discharging to Haller Lake.”
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| Screenshot map courtesy Donna Pacanovsky, SPU |
Black highlighted lines on the screenshot map she provided show the primary conveyance system that discharges to the lake at the points marked by green squares. In addition, local runoff, particularly from properties neighboring the lake, contributes to the lake. Long-time residents say that the lake is also spring fed. The lake’s outflow is an outlet pipe on private property at the west edge of the lake, marked by an orange square. This outlet pipe has an associated valve that can control the release of water from the lake only when the level is high. This outlet system is privately owned and controlled. As shown on the screenshot, the water can go west from that pipe to the retention pond by Ashworth. Haller Lake’s water eventually drains to Lake Union via the Densmore storm drain system. As for explanations for this year’s unusually low lake level, beyond the obvious low rainfall, Ms. Pacanovsky mentioned: “Evaporation: Evaporation was likely much greater this year due to our hotter summer temperatures and longer dry spell. Ground water recharge from the lake: I would assume this remains pretty constant over the years, although recharge from the lake to groundwater could have been greater than normal this past year due to the hotter drier weather... If recharge from the lake were greater this year, this could potentially also result in a lower lake level.”
Thank you to everyone who contributed input into this article! Please email me if you are interested in joining the Friends of Haller Lake Meridian Street End Volunteer Group.
Carolyn Crockett, ccrockett@mac.com
Haller Lake Community Club Parks Committee
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