Meeting Summary
Tuesday, November 26, 2013, 7:00-9:00 PM
The Hearthstone, 6720 East Green Lake Way N
Board Room
Recorder: Davis Patterson
Attendees:
Joan Hardy, our Guest Speaker
Richard FlemingBrian deLucaKaren KoKaren SchuurMarcia NormanKevin StoopsGaret MungerRob Zisette
Guest: Joan Hardy
Joan Hardy spoke about cyanobacteria (bluegreen algae) occurrence and the cyanotoxins they produce. Dr. Hardy along with other Washington State DOH associates, Debra Bouchard, Beth LeDoux, Sally Abella of King County, and Dr. Jean Jacoby of Seattle University studied cyanobacteria and the toxins produced in Puget Sound Lakes under a five year CDC grant. Dr. Hardy talked about results of the studies and the public health implications of cyanobacteria blooms, as well as the posting of informational signs at affected lakes.
The following are selected highlights from the presentation and discussion.
- Microcystin are the toxins we have the most problem with in Green Lake. Other toxins including Saxitoxin and cylindrospermopsin are not a big issue in this region. The DOH focus is exposure pathways. Recreational activities—swimming, boating, etc.–bring lake visitors in contact with cyanotoxins. Cyanotoxins in drinking water are a problem in some areas, but rarely in WA state.
- The legislature voted to fund Freshwater Algae Control Program (2005) through a tax on boats. Some monies from this fund are available to fund a small grant program which citizen groups such as FOGL can apply for. Because Green Lake doesn’t allow public access to motorized vessels, FOGL is not eligible to apply for this small grant program, established in 2007. Joan will see if there’s a way for FOGL to partner with other lakes.
- There are no national guidance values for toxin exposures (yet). DOH offers technical advice. Its recommendations are not law. Seattle-King County Public Health has the authority to take action.
- The framework for testing was developed for protecting health, so worst case scenario drives the protocol. Test results are not intended to be representative of the lake as a whole. Therefore, samples are collected from areas within a lake where the scum is present, even if other use areas have little or no scum. Lake closure only for special cases with high concentrations where access can be controlled.
- Can we determine why lakes are doing well vs. poorly? The DOH study is going to try to understand factors distinguishing more and less toxic lakes.
- DOH is also looking at what causes the algae to produce toxins. It appears that it might be related to oxidative stress. There may be natural selection at work for species that are toxic.
- Seasonality: cyanobacteria in many lakes increase over the summer, as does toxicity (measuring June-October). Increases correlate with amount of sunshine, higher temperatures. Green lake has had blooms during fall and winter seasons
- Joan might be able to buy some test kits for us. Our current kit expires in January. She might be able to work through Ecology and DOH to get some.
- At the web site (nwtoxicalgae.org) one can search a database of WA lakes for toxins. The data can be organized to make charts.
- Higher concentrations in deep water than shallow water in study of lake sediments
- Other studies or study ideas:
- Another study of bioaccumulation of microcystins in mussels in Puget Sound is being done.
- Crayfish are harvested in Green Lake and Lake Washington. But they’re not filter feeders, so they don’t feed on algae. Corbicula (invasive Asian clam) are another candidate for study/monitoring.
- Implications for Green Lake:
- Press release should come before putting special signs up.
- Permanent signs are a good idea for education, located where people, especially small children, are accessing the water. Can consider creating a natural barrier in areas where scum tends to accumulate. However, it depends on wind. Park Dept. would need to have a good rationale to limit access. Something for FOGL and Park Dept. to consider.
- Phosphorus has markedly increased over the last two years, and it’s correlated with blooms.
- Joan will follow through with colleagues about the idea of permanent signs.
- Milfoil has increased over the ten years–possibly a correlation with phosphorus levels throughout the lake.
- If we can think of a study involving Green Lake along with other lakes, we might be able to get included. FOGL should continue to work with Sally Abella to keep us in mind to include Green Lake in studies, especially regional studies.
- FOGL could also work with Seattle-King County Public Health, Ronda Kaetzel. The public health message is to protect children and tie into risk communication–which is very tricky and needs a professional, because we don’t want to scare people.
- Could we model signs after fire danger signs (with an arrow/color system indicating level of risk) or some facsimile? There could be permanent component of signs with education, and a temporary component, perhaps with localized information for each area. This is where FOGL could be involved, partnering with Parks Dept.
- Two main concerns: what’s happening in the lake to increase the blooms, and how can we communicate with public for education and risk communication.
- Green lake is unique in that it is surrounded by park properties and has very high visitor numbers. It requires a unique protocol for testing and risk communication.
- Liability issues: whoever is responsible can be sued if there is a problem, so FOGL doesn’t want to be responsible, but we can play a role in working to establish a system.
- There needs to be a protocol with coordination between Parks and the health department for determining actions. One of the problems is that the risk can move from place to place, which is why we need permanent educational signs.