Peavey Lake (DNR ID: 27-0138-00)
Sampling Location GPS Coordinates: Surface Area: 9 acres Max. Depth: 63 ft
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Peavey Lake is located near the cities of Long Lake and Wayzata. Head east on Minnetonka Blvd, and turn left on Co Rd 101 S. Turn right at Grays Bay Blvd and enter the Grays Bay Marina and public access on the left side of the road.
Peavey Lake is on Lake Minnetonka which is a class 2B lake protected for aquatic life and recreation. Water quality information is available beginning in 1974. MCWD staff have been monitoring the site on Peavey Lake 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) | 1.3 - 3.3 | 2.0 | 50 | C |
| Surface TP (µg/L) | 36 - 95 | 63.2 | 64 | C |
| Chlorophyll-a (µg/L) | 3 - 81 | 38.4 | 66 | C |
| Overall Score | 60 | C |
The following summary refers to Figure 3.35 (a-d).
- Secchi disk increased from 1.3 m to 3.4 m by late May. From early June to late August, there was an overall decline in Secchi disk depth. In early September, Secchi disk increased to 2.1 m then declined to 1.8 m by the early October (standard > 1.4 m).
- Chlorophyll-a concentrations decreased from 12 μg/L to 3 μg/L by early June. Chlorophyll-a concentrations increased from the middle of June to late July reaching a maximum concentration at 81 μg/L. Concentrations fluctuate throughout August and then
declined to 29 μg/L by the end of the season (standard < 14 μg/L). - Surface TP concentrations decreased from 58 μg/L in late April to 33 μg/L by late May, and then increased to 95 μg/L by late July (standard < 40 μg/L). However, in early July, TP concentrations declined to 50 μg/L, before peaking in late July. TP concentrations decreased until early October when TP concentrations were 3.5 times the standard limit.
Surface SRP concentrations were below detection limit (< 0.005 μg/L) except in early May, late July, and the period from late August to early October. - Bottom TP concentrations fluctuated throughout the season ranging between 7272 μg/L and 9510 μg/L. Bottom SRP concentrations increased from 4590 μg/L and 8120 μg/L by late May, and then declined to 4130 μg/L in early June. The remainder of the season SRP concentrations fluctuated between 6200 μg/L and 8850 μg/L. SRP concentration was
greater than TP which may be due to the presence of silica within the sample (email correspondence; RMB, 2009).
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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