It’s renewal time for the 2024 Lake Owasso aquatic plant treatment program. A different approach (whole lake treatment) using fluridone to target Eurasian Watermilfoil (EWM) is planned for 2024.
Good news:
- Fluridone offers greater control of EWM (an invasive species and the plant most problematic on Lake Owasso).
- In select cases the DNR has approved fluridone applications.
- Fluridone offers multi-year EWM protection, expected to last 3-5 years.
- Successfully used on other area lakes.
Bad news:
- Fluridone is especially effective against EWM, but more costly than traditional treatment. **2024 treatment cost will more than double**. (2025 treatment costs are expected to return to pre-2024 levels).
How is a fluridone application expected to benefit Lake Owasso?
- Improved navigation
- Less restricted fishing
- Better quality swimming areas
- Restored balance of native plant and fish species
What does this mean for my 2024 fee?
- Fee assessment for 2024: A onetime special assessment of $250 *** Without the special assessment a fluridone treatment will not be possible, enabling the EWM problem to grow worse.
- Plus $5.00 per allowed shoreline foot (same as last year)
- Annual membership dues of $10
Example: (“allowed” = up to 100′ or 50% of owned shoreline, whichever is less. e.g. own 80′, max allowed 40′. Cost would be 40′ x $5.00 = $200 + $250 onetime special assessment + $10 membership for $460 total.) If your lot is less than 70′ you are allowed up to 35 feet of treatment.
Background
At the 2023 annual meeting and in a Fall email, we reported on fluridone as a whole lake treatment option to combat the ever-increasing challenge of EWM control. (Read more on our FAQ page) Various nearby metro lakes have applied fluridone with excellent multi-year EWM control. After additional research and discussion with professionals and other lake associations, the LOA board has concluded that a 2024 fluridone treatment will provide for the best health of Lake Owasso. In response to the Fall email many of you commented and indicated support for a lake wide fluridone application and were anxious for action sooner rather than later.
In the 9/26/2023 correspondence, we reported on two timing options for a fluridone application: 1) fall of 2024 or 2) spring of 2025. Since that time the LOA board has voted to seek DNR approval for an early spring 2024 treatment. There are two reasons for this adjustment. One, the persistence of EWM even up to ice over necessitates earlier vs later action. Second, a fall 2024 fluridone treatment would have still resulted in a traditional spring 2024 treatment thus adding additional costs for participating lake residents.
As a fallback (e.g. in the event of an extremely late ice-out) the LOA board is leaving a fall 2024 or spring 2025 fluridone treatment option in place as a backup plan. There is no guarantee a fluridone treatment on Lake Owasso will be totally successful. However, the results from other metro lakes using fluridone have shown excellent multi-year EWM control.
While traditional treatment requires about 10 days to take effect, a drawback of fluridone is that it requires about 8-10 weeks for EWM suppression. Hence the plan is to treat shortly after ice-out to allow sufficient fluridone exposure time to help early season navigation. After the main fluridone treatment, there will be 2 or 3 fluridone bump treatments to keep fluridone at 4 ppb. Various native plants are expected to partially fill voids left in the absence of EWM. Thus in 2025 and beyond, we expect traditional treatment toward non-EWM plants reaching nuisance levels.
Long-term data is limited; however, the expectation is that a fluridone treatment could be repeated every 4th or 5th year. Also with limited historical data, is the amount of traditional treatment necessary in “in-between” years. Some lakes have been able to lessen traditional treatment (and associated costs) for those years between fluridone applications.