Data period: through 2017

Town County Delorme Map # True Basin Flushing Rate
ORRINGTON PENOBSCOT 23 1 4.31 flushes/yr
Maximum Depth Average Depth Surface Area Lake Volume Drainage Area
7 m
(24 ft) 		3 m
(9 ft) 		40 ha
(99 ac) 		1,069,789 m3
(867 ac-ft) 		9 km2
(3.4 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
1989 3.5 4.4 4.8 2
1990 5.5 40 6.6 8 4.7 4.7 4.7 1 4.5 4.5 4.5
1996 6.0 31 7.0 20 23 3.7 3.7 3.7 1
1997 8.0 38 7.0 10 15 3.9 5.1 6.2 6 6.1 6.1 6.1
1998 3.8 4.3 4.8 3
1999 4.1 4.7 5.2 3
2000 5.3 5.4 5.6 2
2001 4.4 5.0 6.7 4
2002 2 9.5 50 22 13 4.3 5.3 6.3 4 2.2 2.2 2.2
2003 4.9 5.2 5.6 3
2004 4.8 4.9 5.0 3
2005 4.8 5.2 5.7 3
2006 4.3 4.8 5.3 3
2007 16 7.4 39 7.1 7 19 5.0 5.4 6.0 3 2.7 2.7 2.7
2008 4.7 5.1 5.5 2
2009 3.4 3.9 4.2 3
2010 5.3 5.7 5.8 2
2011 18 8.2 40 7.1 7 4.3 4.8 5.2 2
2012 3.4 3.5 3.5 1
2013 4.5 4.6 4.6 1
2014 4.0 4.3 4.5 2
2015 4.4 4.7 5.0 2
2016 17 10.0 45 7.1 9 5.3 5.3 5.3 1 2.5 2.5 2.5

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
13 7.8 40 6.9 13 7 18 3.4 4.8 6.7 2.5 2.2 3.6 6.1

Most recent late summer temperature and dissolved oxygen profiles

Units: Temperature (TEMP) = °C; Dissolved Oxygen (DO) = mg/L
1990-08-17
1996-09-19
1997-08-14
2002-08-15
2007-08-14
2016-08-16
Depth (m) TEMP DO TEMP DO TEMP DO TEMP DO TEMP DO TEMP DO
0 26 8.1 17 8.2 23 7.6 27 8.0 23 7.9 24 8.5
1 25 8.2 17 8.2 23 7.5 27 7.9 23 7.9 24 8.5
2 24 8.0 17 8.2 23 7.5 26 8.2 23 7.9 24 8.5
3 24 8.0 17 8.0 23 7.4 24 8.0 23 7.9 24 8.3
4 22 4.8 17 8.0 23 7.2 23 7.0 22 7.1 24 7.7
5 18 0.7 17 8.0 20 2.0 20 2.6 19 4.5 22 3.2
6 15 0.4 16 2.4 16 0.2 16 0.7 15 1.0 17 0.4
7 13 0.3 14 0.4 13 0.1 14 0.2 13 0.1
8 13 0.3 14 0.4 13 0.1 14 0.2 12 0.1
9 13 0.2 14 0.3 13 0.1

Recent temperature and dissolved oxygen profile plots

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