Data period: through 2017

Town County Delorme Map # True Basin Flushing Rate
ROCKPORT KNOX 14 1 0.82 flushes/yr
Maximum Depth Average Depth Surface Area Lake Volume Drainage Area
20 m
(66 ft) 		9 m
(28 ft) 		44 ha
(109 ac) 		3,760,844 m3
(3,049 ac-ft) 		5 km2
(1.8 mi2)

Secchi Disk Transparency Graphs

Graph Legend: Secchi symbols = average Secchi Disk Transparency Values; tick marks = maximum and minimum values for each year.

## [1] "No 2017 Secchi Disk Transparency Data"

Water Chemistry and Trophic State Parameters

Table Legend:

Color: Color (SPU), Alk: Alkalinity (mg/l CaCO3), SpCon: Specific Conductivity (\(\mu\)S/cm), pH: pH (standard units)

TP = Total Phosphorus (\(\mu\)g/L) – EC: Epilimnion Core, SG: Surface Grab, BG: Bottom Grab, PG: Profile Grab

SDT = Secchi Disk Transparency (m) – Min: minimum value, Avg: average value, Max: maximum value, n: number of months with Secchi readings per year, b: number of times Secchi disk was observed touching the bottom of the lake per year

Chl = Chlorophyll-a (\(\mu\)g/L) – Min: minimum value, Avg: average value, Max: maximum value
Year Color Alk SpCon pH TP-EC TP-SG TP-BG TP-PG SDT-Min SDT-Avg SDT-Max SDT-n SDT-b Chl-Min Chl-Avg Chl-Max
1974 6.7 6.7 6.7 1
1975 5 6.4 7.0 7.9 4
1976 3.8 6.0 8.2 5
1978 3.9 30 5.2 7.7 9.9 6
1982 10.0
1984 31.0
1986 6.2
1987 14.0
2008 4.0 8.4 8.6 8.9 1 2.1 2.1 2.1

Lake Chemistry and Trophic Summary Data - Overall Summary Values:

Avg Color Avg Alk Avg SpCon pH Avg TP-EC Avg TP-SG Avg TP-BG Avg TP-PG SDT-Min SDT-Avg SDT-Max SDT-n Chl-Min Chl-Avg Chl-Max
3.9 30 13 5 3.8 7.2 9.9 3.4 2.1 2.1 2.1

Most recent late summer temperature and dissolved oxygen profiles

Units: Temperature (TEMP) = °C; Dissolved Oxygen (DO) = mg/L
1978-08-07
1978-09-01
Depth (m) TEMP DO TEMP DO
0 22.5 8.7 21.1 8.5
1
2 22.0 8.8 20.1 8.4
3
4 21.5 8.8 20.1 8.5
5
6 21.0 8.9 19.8 8.5
7 15.0 11.0 18.0 9.1
8 11.3 11.6 12.2 10.8
9 10.0 11.9 10.2 11.6
10 9.0 12.0 9.1 11.6
11 8.1 12.0 8.2 11.3
12 7.8 11.8 7.8 11.0
13
14 7.1 11.6 7.0 9.4
15
16 6.8 11.2

Recent temperature and dissolved oxygen profile plots

Temperature (°C), Dissolved Oxygen (mg/L)