Data period: through 2018

Town County Delorme Map # True Basin Flushing Rate Elevation
OLD TOWN PENOBSCOT 33 1 1.96 flushes/yr 115 ft
Maximum Depth Average Depth Surface Area Lake Volume Drainage Area
8 m
(28 ft) 		3 m
(10 ft) 		2,045 ha
(5,054 ac) 		65,500,000 m3
(53,102 ac-ft) 		195 km2
(75 mi2)

Secchi Disk Transparency Graphs

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

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
1994 15 15 3.6 3.9 4.2 2
1995 2.6 3.9 5.9 6
1996 2.5 2.9 3.3 5
1997 2.9 3.9 4.7 6
1998 2.0 3.5 4.7 8
1999 2.8 3.5 4.0 5
2000 2.4 2.7 3.0 5
2001 2.8 3.6 4.8 5
2002 2.8 3.7 4.0 3
2003 2.6 3.4 4.7 3
2004 2.9 3.3 3.6 4
2005 2.7 2.9 3.5 3
2006 22 2.6 2.8 3.3 3
2007 33 18 66 7.5 18 2.6 3.7 4.4 6 3.5 3.5 3.5
2008 18 2.6 3.0 3.5 6
2009 18 2.3 2.9 3.4 4
2010 17 2.4 3.4 4.6 5
2011 16 2.9 3.2 3.5 4
2012 2.3 3.2 4.4 5
2013 2.8 3.0 3.7 5 2
2015 17 3.0 3.5 4.1 5
2016 17 2.7 3.2 3.6 2
2017 23 2.0 3.0 3.5 4
2018 20 2.3 3.1 3.8 5

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
33 18 66 7.5 16 18 15 2 3.3 5.9 4.5 3.5 3.5 3.5

Temperature and Dissolved Oxygen Profiles

Late summer only; limited to eight most recent profiles

Units: Temperature (TEMP) = °C; Dissolved Oxygen (DO) = mg/L
2015-09-12
2016-08-30
2017-08-14
2017-08-23
2017-09-08
2018-08-13
2018-08-26
2018-09-09
Depth (m) TEMP DO TEMP DO TEMP DO TEMP DO TEMP DO TEMP DO TEMP DO TEMP DO
0 24 7.9 23 8.1 24 8.5 24 8.4 20 8.2 26 8.1 24 8.3 23 8.2
1 23 7.9 23 8.0 23 8.3 24 8.4 19 8.2 26 7.9 24 8.2 23 8.2
2 23 7.7 23 8.0 23 8.2 23 8.3 19 7.9 26 7.6 24 8.1 22 8.1
3 23 7.5 23 7.9 23 8.1 23 8.1 19 7.8 26 7.5 24 8.1 22 7.9
4 23 7.3 23 7.8 23 8.1 23 8.1 19 7.8 26 7.5 24 8.1 22 7.9
5 22 7.2 23 7.6 23 8.0 23 8.0 19 7.7 26 7.5 24 8.1 22 7.9
6 22 7.1 23 7.6 23 8.0 23 8.0 19 7.7 25 7.0 24 8.0 22 7.7
7 22 7.1 23 7.6 23 8.0 23 7.0 19 7.7 25 6.7 24 8.0 22 7.6
8 22 7.0 22 7.3 23 8.0 25 5.6 23 7.9 22 7.5
9 23 7.9 22 7.5

Most recent temperature and dissolved oxygen profile plots

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