Blackman Lake restoration plan uses plants to help lake health





SNOHOMISH —  A few native plants could go a long way to helping rehabilitate Blackman Lake. Not to mention making it unfavorable for those pesky geese.
This fall, the city plans to add a five-foot buffer of salal shrubs and similar native plants along the lakefront, with some cutouts for people to access the water.
It’s the latest solution to a longstanding problem: The lake’s oxygen levels are low, which makes a breeding ground for unwanted algae.
The geese make a big footprint on the lake. How? The straight poop is their droppings are full of nitrates and phosphorous. The nitrates rob water of oxygen. The algae loves that enriched water and flourishes. Everything else relying on that oxygen, such as fish, gets strangled for air. You end up with a murky lake.
So says years of lake research on what’s called eutrophication.
The re-vegetation project follows a recommendation in a county report on the lake’s water clarity.
Right now geese mingle and nest near the swimming area between two fishing docks at Hill Park. Native species can detour geese away.
“We’ve been talking a long time about how to get rid of this goose problem we have,” city parks director Mike Johnson commented.
Fertilizer runoff from yards (and sewage) also accelerate the nitrates that lead to a lake’s death.
A Snohomish High science class measured the lake’s pulse this spring and at that time found the water quality has high levels of fecal coliform.
Some other steps done for lake health have included replacing the fishing docks approximately five years ago with new ones that let water flow underneath better, and moving a storm water conduit so it no longer discharged in the lake’s swimming area.
Blackman Lake got its name from the Blackman brothers, two giants in the logging business during Snohomish’s pioneer days of the late 1800s. The Blackman House Museum on Avenue B once was the youngest brother’s personal home.


Recommendations for a lake-friendly landscape plan
In a Riparian Zone: Lady fern, sedges (many species), flag iris
Lower Bank Shrubs: redosier dogwood, red elderberry, evergreen huckleberry; Ground Covers: lady fern, bunchberry, sword fern; Shade trees: chokeberry, Oregon ash, western hemlock; Shade and Cover:vine maple, western crabapple, hazelnut
Upper Bank: Shrubs: serviceberry, mock orange, red flowering currant; Ground Covers: salal, sword fern,pig-a-back; Shade Trees: Chokeberry, Oregon ash,western hemlock; Shade & cover: Vine Maple, western crabapple, hazelnut
 — Source: “The Washington Lake Book,” 2007, first published by the Washington State Lake Protection Association