Stubbs Bay (DNR ID: 27-0133-12)
Sampling Location GPS Coordinates: Surface Area: 195 acres Max. Depth: 37 ft
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Stubbs Bay is located near the city of Orono. Head east on Minnetonka Blvd, and turn left on Co Rd 101 S. Turn right at Grays Bay Blvd and continue on Bushaway Rd. Turn left on Eastman Ln/Shady Ln, then a slight right at E Circle Dr. Next take a slight left at Lake St. E. Turn left at Ferndale Rd S and continue on Shoreline Dr. Turn right at Northshore Dr and then turn right at Tonkawa Rd to enter the public boat access area.
Stubbs Bay is on Lake Minnetonka which is a class 2B lake protected for aquatic life and recreation. Water quality information is available beginning in 1996. MCWD staff have been monitoring the site on Stubbs Bay on a bi-weekly basis from the time of ice out (April) to the time of fall mixing (mid-October) since 2006.
See Previous Reports.
Monitoring season started in late April and ended in late October. A YSI multi-probe sonde was used to measure dissolved oxygen (DO), temperature (oC), pH, and specific conductivity (µS/cm) at each meter depth from the water surface to the bottom. Additionally, water samples were collected within the first two meters of the surface with a 2-meter composite sampling tube. Samples one meter above the bottom were collected with a Van Doran water sampler. Surface sample were analyzed for total phosphorus (TP), soluble reactive phosphorus (SRP), total nitrogen (TN), where the bottom samples were analyzed for TP and SRP. Surface concentrations of chlorophyll-a were also analyzed and measurements of Secchi disc depth were recorded.
| 2009 Summer Water Quality Summary |
| Parameters | Range | Mean | TSI Value | Lake Grade |
| Months | June - Sept. | May - Sept. | ||
| Secchi Depth (m) | 0.7 - 2.0 | 1.0 | 60 | C |
| Surface TP (µg/L) | 35 - 49 | 41.2 | 58 | C |
| Chlorophyll-a (µg/L) | 10 - 47 | 27.3 | 63 | C |
| Overall Score | 60 | C |
The following summary refers to Figure 3.47 (a-d).
- Secchi disk depth increased from 0.8 m to 4.1 m by late May. The rest of the season, Secchi disk depth decreased ranging from 0.7 m to 1.5 m (standard > 1.4 m). No Secchi disk depth was recorded in early October.
- Chlorophyll-a concentrations decreased from 40 μg/L to 2 μg/L by late May. Then from early June to late August, chlorophyll-a concentrations rose to 47 μg/L three times the standard limit (< 14 μg/L). The rest of the season concentrations declined that by the end of the season concentrations were 31 μg/L.
- Surface TP concentrations decreased from 66 μg/L to 35 μg/L by early June, than fluctuated between 36 μg/L and 49 μg/L until the end of the season. In early October, TP concentrations rose to 90 μg/L two times the standard limit (< 40 μg/L). Surface SRP
concentrations were below detection limit (< 0.005 μg/L) except in late May, August and from late September to early October. - Both bottom TP and SRP concentrations increased from late April to the late September before declining in early October. Maximum concentrations for TP were 846 μg/L and SRP were 789 μg/L.
Lake Grades and Historical Monitoring Summaries
When available, previous reports are linked to applicable year. Additional lake data previous to 2007 may be available in the applicable year's hydrodata report. If you have additional questions or you are looking for specific information please contact MCWD's Water Quality Staff.
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