Volunteer Lake Assessment Program Individual Lake Reports
BEAVER LAKE, DERRY, NH
MORPHOMETRIC DATA
TROPHIC CLASSIFICATION
Watershed Area (Ac.): 5,760
Surface Area (Ac.):
134
Shore Length (m):
5,800
Max. Depth (m): 14
Mean Depth (m): 5
Volume (m³):
2,707,500
Flushing Rate (yr¹) 4.1
P Retention Coef: 0.47
Elevation (ft):
287
Year
KNOWN EXOTIC SPECIES
Trophic class
1985
EUTROPHIC
1999
MESOTROPHIC
The Waterbody Report Card tables are generated from the DRAFT 2014 305(b) report on the status of N.H. waters, and are based on data collected from 20042013. Detailed waterbody assessment and report card information can be found at www.des.nh.gov/organizations/divisions/water/wmb/swqa/index.htm
Designated Use
Parameter
Category
Comments
Aquatic Life
Phosphorus (Total)
Slightly Bad
The calculated median is from 5 or more samples and is > indicator and the chlorophyll a indicator is exceeded.
pH
Slightly Bad
>10% of samples exceed criteria by a small margin (minimum of 2 exceedances).
Oxygen, Dissolved
Encouraging
There are < 10 samples with 0 exceedances of criteria. More data needed.
Primary Contact Recreation
Dissolved oxygen satura Slightly Bad
There are >10% of samples (minimum of 2), exceeding criteria.
Chlorophyll-a
Slightly Bad
The calculated median is from 5 or more samples and is > indicator.
Escherichia coli
No Data
No data for this parameter.
Chlorophyll-a
Very Good
There are a total of at least 10 samples with 0 exceedances of indicator.
BEACH PRIMARY CONTACT ASSESSMENT STATUS
BEAVER LAKE - PARK BEACH
Escherichia coli Very Good
Where there are no geometric means, all bacteria samples are < 75% of the geometric mean. Where
there are geometric means all single bacteria samples are < the SSMC and all geometric means are <
geometric mean criteria.
BEAVER LAKE - GALLIEN'S BEACH
Escherichia coli Bad
There are >=1 exceedance(s) of the geometric mean and/or >=2 single sample criterion exceedances.
One or more exceedance is >2X criteria.
BEAVER LAKE - COMEAU'S BEACH
Escherichia coli No Data
No data for this parameter.
WATERSHED LAND USE SUMMARY
Fry, J., Xian, G., Jin, S., Dewitz, J., Homer, C., Yang, L., Barnes, C., Herold, N., and Wickham, J., 2011. Completion of the 2006 National Land Cover Database
for the Conterminous United States, PERS, Vol. 77(9):858-864. For larger image contact NHDES.
Land Cover Category
Open Water
% Cover
Land Cover Category
Barren Land
0.05
Land Cover Category
Grassland/Herbaceous
% Cover
1.13
% Cover
Developed-Open Space
5.16
Deciduous Forest
44.15
Pasture Hay
7.07
Developed-Low Intensity
12.7
Evergreen Forest
12.38
Cultivated Crops
1.1
Developed-Medium Intensity
2.67
Mixed Forest
3.84
Woody Wetlands
2.83
Developed-High Intensity
0.03
Shrub-Scrub
3.77
Emergent Wetlands
3
0.01
Volunteer Lake Assessment Program Individual Lake reports
Beaver Lake, Derry
4 Data Summary
Observations and Recommendations Refer to Ta le 1 and Histori al Deep Spot Data Graphi s)
 Chlorophyll-a: Chlo oph ll le els e e ele ated i Ju e a d Jul > . ug/L a d e e app oa hi g le els
i di ai e of a algal loo
ug/L . Chlo oph ll le els had de eased to < . ug/L Septe e . Histo i al
t e d a al sis i di ates elai el sta le hlo oph ll le els si e o ito i g ega , ho e e a e age le els
i eased i
a d
.
 Conductivity/Chloride: Deep spot a d t i uta o du i it a d hlo ide le els e e ele ated a d u h
g eate tha the state edia s. Co du i it a d hlo ide o i ue to e g eatest at Cat-o-B ook, pa i ula l at
Bea e Rd. Histo i al t e d a al sis i di ates elai el sta le epili ei uppe ate la e o du i it ith
ode ate a ia ilit et ee ea s.
 Total Phosphorus: Epili ei phospho us le els de eased f o Ju e to Septe e a d the
a e age as
less tha the state edia . Histo i al t e d a al sis i di ates sta le epili ei phospho us le els ith ode ate
a ia ilit et ee ea s. Metali ei
iddle ate la e phospho us le els e e slightl a o e a e age, ut
sta le th oughout the su
e . H poli ei lo e ate la e phospho us le els e e ele ated i Septe e
likel due to the elease of phospho us a d o ga i o pou ds f o
oto sedi e ts u de a o i o diio s.
Ma te B ook phospho us le els e e a e age fo that staio , a d Cat-o-B ook phospho us le els e e ele ated
likel due to etla d i lue es.
 Transparency: T a spa e
as u h less tha o al i Ju e due to ele ated algal g o th, ho e e i p o ed
a d e ai ed sta le i Jul a d Septe e . T a spa e
has o i uall i p o ed si e
, hi h is a good
sig . Histo i al t e d a al sis i di ates sta le t a spa e
ith high a ia ilit et ee ea s.
 Turbidity: Epili ei tu idit as elai el lo , etali ei tu idit as slightl g eate i Jul a d
Septe e likel due to algal g o th, a d h poli ei tu idit as ele ated i Septe e likel due to the
elease a d fo aio of o ga i o pou ds du i g a o i o diio s. Cat-o-B ook phospho us le els i eased
as the su
e p og essed likel due to lo lo o stag a t o diio s.
 pH: pH le els e e sui ie t to suppo t a uai life, ho e e h poli ei pH le els ha e histo i all ee less
tha desi a le a ge . - . u its. Histo i al t e d a al sis i di ates sta le epili ei pH le els si e o ito i g
ega .
 Dissolved Oxygen/Temp: Dissol ed o ge le els e e ze o f o the etali io th ough the h poli io i
Jul . This i di ates a i h o ga i la e at the lake’s oto
he e iologi al a i it uses up o ge th oughout
the su
e . This ould lead to phospho us elease f o sedi e ts that ould suppl algae a d a o a te ia
ith ut ie ts e essa fo g o th.
 Recommended Actions: Algal g o th as ele ated i Ju e a d Jul pote iall due to phospho us loadi g f o
sp i g s o
elt a d sto
ate u of. Ide if i g a d edu i g phospho us loads f o the ate shed should
o i ue to e a p io it . Li it fe ilize use a d use phosphate f ee fe ilize if e essa . Ide if a eas of
sto
ate u of i to the lake a d i ple e t est a age e t p a i es to aptu e a d i ilt ate sto
ate
efo e e te i g the lake. Co du i it a d hlo ide o i ue to e ele ated. Edu ate ate shed eside ts o the
p ope use of de-i i g ate ials o thei d i e a s a d alk a s to help edu e salt loadi g. C a o a te ia e e
do i a t i the Jul algal sa ple. Wat h fo a o a te ia loo s o su fa e s u s a d oif DES i
ediatel if
oi ed. C a o a te ia ha e the a ilit to p odu e to i s that ould e ha ful to pets a d hu a s. Keep up the
g eat o k!
Staio Na e
Ta le .
A e age Wate Qualit Data fo BEAVER LAKE
Alk. Chlo -a Chlo ide Co d. Total P
g/l ug/l
g/l
uS/
ug/l
Epili
io
.
.
NH Water Qualit Sta dards: Nu e i
spe ii pa a ete s. Results e eedi g
o side ed a ate ualit iolaio .
Chloride: >
g/L h o i
E. oli: >
ts/
L – pu li ea h
E. oli: >
ts/
L – su fa e ate
Tur idit : > NTU a o e atu al le el
pH: et ee . - . u less atu all o
.
T a s.
NVS
VS
.
.
Tu .
tu
pH
.
.
Metali
io
.
.
.
H poli
io
.
.
.
Cat O B ook
.
.
.
Cat-O-Bk. at Bea e Rd
.
.
.
Ma te B ook
.
.
.
ite ia fo
ite ia a e
s
u i g
NH Media Values: Media alues fo spe ii pa a ete s ge e ated f o histo i lake o ito i g data.
Alkali it : .
g/L
Chloroph ll-a: .
g/
Co du ivit : . uS/
Chloride:
g/L
Total Phosphorus: ug/L
Tra spare : .
pH: .
Historical Water Quality Trend Analysis
Para eter
Co du i it
pH epili io
Tre d
Sta le
Sta le
This epo t as ge e ated
E pla aio
Para eter
T e d ot sig ii a t, data ode atel a ia le. Chlo oph ll-a
T e d ot sig ii a t, data sho lo a ia ilit . T a spa e
Phospho us epili
the NH DES Volu tee Lake Assess e t P og a
VLAP . Fo
o e i fo
io
aio
Tre
Sta
Sta
Sta
d
le
le
le
o ta t VLAP at
E
T
T
T
pla
e d
e d
e d
aio
ot sig ii a t, data sho lo a ia ilit .
ot sig ii a t; data highl a ia le.
ot sig ii a t, data ode atel a ia le.
-
o sa a.stei e @des. h.go