Lake Level Control Sub-Committee Meeting Minutes
November 13, 2013
Members present include Gil Kendrac, Dave Flaum, Dave Emick, Todd Gress, and Chairman Rick Gainar. Also present was RRA Board Member Dell Rogers.
Meeting called to order at 2PM at the Association Office.
1. Discussed the recent lake turnover event that occurred on or about 10/24/2013 and the subsequent algal bloom. O2 and temperature data collected on 10/4/2013, while the lake was still stratified, was compared to data collected after the lake turnover on 10/24/2013. Before the turnover temperatures ranged from 21.5ºC at the surface to 12.5ºC at 31-foot level while dissolved oxygen ranged from 10.4 mg/L to 0mg/L at the 17-foot level and below. After the lake turnover temperatures remained constant throughout the water column at 5.2ºC. Dissolved oxygen was also nearly constant ranging from 1.6 mg/L at the surface to 0mg.L at the 29-foot level.
2. Lake turnover is an annual event at Roam Rock Lake. So is the subsequent, massive algal bloom that follows this event after a few days time. The lake turnover event causes the phosphorus that was released from the organic sediment but held at the lake bottom all year, to mix in the entire water column.
3. We discussed the model siphon that a team of committee members recently installed at the dam using a length of garden hose. Dissolved oxygen data is currently being collected from lake water 5-feet off the bottom. Phosphorus data collection will soon follow.
4. No report from the Lowrey/Martin work group on their investigation of the water/sewage lines that cross a cove near the dam. We will need to understand the effect a freezing, winter drawdown would have on these lines.
5. A discussion ranking 13 advantages of a siphon spillway determined that the committee felt that less phosphorus & nutrients, improved weed control, and ability to maintain lake level for emergency repairs were among the most important. A siphon design with the ability to keep up with 100% of expected water flowing into the lake would be necessary.
Our next meeting is scheduled on December 11, 2013 at 2:00PM. Our regular meeting date is the 2nd Wednesday of each month at the Association Office so mark your calendars!
Meeting was adjourned at 3:45PM
by RD Gainar on November 14, 2013