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Thomas Maguire, MassDEP March 2014
Climate Change Implications for Stormwater Management in Massachusetts
R² = 0.4
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1860 1880 1900 1920 1940 1960 1980 2000 2020
Tem
pe
ratu
re (
oF)
Boston, MA: Temperature Average Annual 1873 to 2013
2012
2010
1875
1873-2013 Avg: 50.7oF
1881-1910 Avg: 49.4oF
1981-2010 Avg: 51.7oF
Average Compiled from Boston WSFO and NCDC data
R² = 0.04
0
10
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1860 1880 1900 1920 1940 1960 1980 2000 2020
Pre
cip
itat
ion
De
pth
(in
che
s/ye
ar)
Boston MA: Precipitation, Annual Depth 1881-2013
1981-2010 Avg: 43.77”
1881-1910 Avg: 40.01”
Annual Total and Averages Compiled from MassDCR and NCDC data
R² = 0.04
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
1930 1940 1950 1960 1970 1980 1990 2000 2010 2020
Pre
cip
itat
ion
De
pth
(in
che
s/d
ay)
Boston, MA: Precipitation, Annual Maxima Daily
1936-2013 Avg: 2.77”
Annual Maxima Series compiled from NCDC data
R² = 0.6
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Nu
mb
er
of
Dai
ly S
torm
s/ye
ar
Boston, MA: Precipitation, Storms ≥ 1.5 in/day
Storms ≥ 1.5” Compiled from NCDC data
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
2 yr 24 hr 10 yr 24 hr 25 yr 24 hr 50 yr 24 hr 100 yr 24 hr
Pre
cip
itat
ion
(in
che
s)
Precipitation Return Period Frequency
Boston, MA: Precipitation Return Period Frequency 1961 TP 40 versus 2011 Cornell NRCC
1961 TP40
2011 NRCS-Cornell
26% change
2011 Cornell NRCC
, Massachusetts
Peak Annual Maxima from USGS Gage #01101500 Data
Temperate Climate
, MA
Log Pearson Type III Analysis of USGS Gage #01101500 Data
R² = 0.01
0
5
10
15
20
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30
35
40
Dis
char
ge (
ft3/s
eco
nd
) Quaboag River near West Brimfield: Average Annual Minima Discharge
Annual Minima and Average compiled from USGS Gage #01176000 Daily Data
R2=0.9
Mean Tide Data from NOAA Tide Station 8443970
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20
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120
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Ru
no
ff R
ate
(fe
et3/s
eco
nd
)
Return Period (years)
EFFECT ON RUNOFF RATE
INCREASE IN FLOW RATE FROM 1961
Based on hypothetical 10-acre parking lot in East Boston location
HISTORIC1961
EXISTING 2011
(TP40)
(Cornell NRCC)
0
20
40
60
80
100
120
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Ru
no
ff R
ate
(fe
et3/s
eco
nd
)
Return Period (years)
PROJECTED 2050
HISTORIC1961
EXISTING 2011
PROJECTED ADDITIONAL INCREASE IN FLOW RATE
Based on hypothetical 10-acre parking lot in East Boston location, with CLIMB projection of 0.31% precipitation increase each year
0
20
40
60
80
100
120
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Ru
no
ff R
ate
(fe
et3/s
eco
nd
)
Return Period (years)
PROJECTED 2050
HISTORIC1961
EXISTING 2011
Based on hypothetical 10-acre parking lot in East Boston location, with CLIMB projection of 0.31% precipitation increase each year
0
20
40
60
80
100
120
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Ru
no
ff R
ate
(fe
et3/s
eco
nd
)
Return Period (years)
PROJECTED 2050
HISTORIC1961
EXISTING 2011
Based on hypothetical 10-acre parking lot in East Boston location, with CLIMB projection of 0.31% precipitation increase each year
Stormwater Management Implications
Probable Cause Possible Effect
More runoff - pipe capacity exceeded CSO/SSO Discharge Frequency Increase
More runoff - pipe capacity exceeded Urban street flooding increase
More runoff - detention basin capacity exceeded
Upstream and downstream river flooding increase, increased scour to stream channels and stream culverts
Less snowpack melt/more runoff/higher ET
Less infiltration to groundwater seasonally: impact to drinking waters, wetlands, aquatic life
Snow/Rain mix change in winter Impacts to drinking water and aquatic life from increased salt use on roads
Elevated runoff temperatures Reduced cold water fishery
Elevated temperature in stormwater treatment systems combined with greater time between storms in summer
Algae blooms & bio-magnification of pathogens in stormwater treatment systems, effect on downstream wetlands
Collection and end-of-pipe Stormwater Treatment Systems in Floodplains (e.g. Detention Basins)
Reduced stormwater treatment on more frequent basis due to inundation from coastal and river flooding
Adaptation • Current stormwater collection and treatment
practices in Massachusetts are based on 1938 – 1958 hydrology (TP40, published in 1961)
• Stormwater sizing methods currently in use rely on a design storm approach - static assumptions.
• Current actual as well as projected future hydrology for Massachusetts are greater than TP40.
• Low Impact Development and Environmentally Sensitive Site Design practices provide greater flexibility with lack of stationarity to reduce physical impacts to streams and wetlands, reduce impact to aquatic life, induce recharge, lag runoff, and provide stormwater treatment.
