tributary strategy workgroup discussion of phase 5 watershed model

Tributary Strategy WorkgroupDiscussion of Phase 5 Watershed Model

Jeff SweeneyUniversity of Maryland

Chesapeake Bay Program [email protected]

410-267-9844http://www.chesapeakebay.net/

Tributary Strategy Workgroup Phase 5 MeetingChesapeake Bay Program Office

January 26, 2005

Atmospheric Deposition

Phase 5 Atmospheric Deposition

• Need to know the spatial and temporal variations in the concentrations of dissolved substances in precipitation.

o From monitoring station wet-fall:

Daily precipitation volumes Weekly NH4

+ concentrations Weekly NO3

- concentrations

• Phase 4 Watershed Modelo 15 NADP/NTN monitoring stationso 1984-1992

• Phase 5 Watershed Modelo 29 NADP/NTN monitoring stationso 6 AirMoN monitoring stationso 1984-2001


• Need to know the spatial and temporal variations in the concentrations of dissolved substances in precipitation.

o From monitoring station wet-fall: Daily precipitation volumes Weekly NH4

+ concentrations Weekly NO3

- concentrations

o Wet-fall concentration model yields: Daily NH4

+ concentrations Daily NO3

- concentrations

o Daily precipitation volumes and daily inorganic concentrations yield:

Daily deposition of NH4+ and NO3

- in wet-fall


• Wet-fall concentration model:

Log10(c) = bo + b1log10(ppt) + b2sseason + b3v3 + . . . + bnvn +e

where, c = daily wet-fall ionic concentration (mg/L)

bo = intercept

ppt = daily precipitation volume (inches)b1 = coefficient for precipitation term

season = vector of 5 binary indicator variables encoding the 6 bi-monthly seasonsb2s = vector of 5 coefficients for season terms

v3 . . Vn = additional predictors selected through stepwise regressiono National Land Cover Data (NLCD) Within proximities of 0.8, 1.6, 3.2, 8.0, and 16.1 km of each NADP/NTN site Open water, forested, residential, industrial/transportation, croplands, and vegetated

wetlandso Local emission levels of ammonia and nitrous oxides from EPA National Emission Trends

(NET) County emission totals 1985-1999 County containing each NADP/NTN monitoring site and for the nearest 3 counties

b3 . . bn = coefficients corresponding to v3 . . Vn

e = residual error

Phase 5 Atmospheric DepositionNH4

+ Wet-fall Concentration (mg/L)May 1, 1998

NH4+ Wet-fall Deposition (kg/ha)

May 1, 1998

Estimates produced by applying daily ammonium concentration model to grids of estimated daily precipitation from the National Weather Service Climate Prediction Center’s U.S. Daily

Precipitation Analyses.

Phase 5 Atmospheric DepositionNO3

- Wet-fall Concentration (mg/L)May 1, 1998

NO3- Wet-fall Deposition (kg/ha)

May 1, 1998

Estimates produced by applying daily nitrate concentration model to grids of estimated daily precipitation from the National Weather Service Climate Prediction Center’s U.S. Daily

Precipitation Analyses.

Phase 5 Atmospheric DepositionNH4

+ Wet Deposition (kg/ha)Mean annual (1985-2001)

NO3- Wet Deposition (kg/ha)

Mean annual (1985-2001)

Estimates produced by applying daily ammonium and nitrate concentration model to grids of estimated daily precipitation from the National Weather Service Climate Prediction Center’s

U.S. Daily Precipitation Analyses.

Estimates produced by applying daily NH4+ and NO3- concentration model to estimates of daily precipitation

from a high resolution hourly precipitation model developed by the USGS for river modeling segment in

the CB watershed.

Phase 5 Atmospheric DepositionTotal Inorganic Nitrogen Wet Deposition (kg/ha)

Mean annual (1985-2001)

Estimates produced by applying daily NH4+ and NO3- concentration model to grids of estimated daily precipitation from the National Weather Service

Climate Prediction Center’s U.S. Daily Precipitation Analyses.


• Models-3/Community Multi-scale Air Quality (CMAQ) Modeling System:

o Replaces Regional Acid Deposition Model (RADM) in Phase 5

o Provides estimates of nitrogen deposition resulting from changes in precursor emissions from utility, mobile, and industrial sources due to management actions or growth.

Adjusts deposition determined by wet-fall concentration model and precipitation volumes

o Predicts the influence of source loads from one region on deposition in other regions.

o Provides estimates of wet:dry for nitrate and ammonium.


Atmospheric Inputs:Of the total NOx deposition to the Chesapeake Bay watershed land area, about 50% originates from emissions in Bay-watershed states: PA = 17%, VA = 10%, MD = 9%, WV = 7%, NY = 5%, DE = 1%OH, NC, NY, KY, IN, TN, MI = 27%Other States in 37-State Area = 24%

Animal Nutrient Balance

VolatilizationPasture

Dairy

Uncollected

Collected

Spring/FallApplication

Daily Application

Crop

Enclosure

BarnyardVolatilization

Storage

VolatilizationVolatilization

Volatilization

RunoffRunoff Runoff

Swine

Layers

Broilers

Turkeys

Horses

Beef

Daily Application

Phase 5 Animal Nutrient Balance


Dairy

Uncollected

Collected


Daily Application

Crop

Enclosure


Storage


Volatilization

RunoffRunoff Runoff

Swine

Layers

Broilers

Turkeys

Horses

Beef

Daily Application


In Phase 4, there is no direct connection between estimated storage and handling

losses and the hard-wired load from animal feeding operations, i.e., “manure acres”.


Dairy

Uncollected

Collected


Daily Application

Crop

Enclosure


Storage


Volatilization

RunoffRunoff Runoff

Swine

Layers

Broilers

Turkeys

Horses

Beef

Daily Application

Phase 5 Animal Nutrient BalanceAccounted for in the Watershed Model simulation but, generally, not part of atmospheric deposition

Accounted for in the input decks to the Watershed

Model but, generally, not part of atmospheric

deposition


Ammonia and AmmoniumSources and Emissions

On-Site Wastewater Management Systems(Septic)

Phase 5 Septic Systems and Loads

0.115 0.113

0.404 0.430

0.2850.340

0.330

0.397

0.032

0.0380.020

0.015

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1990 (Calculated) 2003 (Calculated)

(million s

epti

c sy

stem

s)

NY PA MD VA WV DE

2003 Septic EOS Load = 2003 population * 1990 fraction of population on septic * lbs TN/person edge-of-field * pass-through factor

2003 Septic Systems = (2003 population * 1990 fraction of population on septic / 1990 people/system) – state-reported septic connections BMP

1990 Versus 2003Calculated Septic Systems


0.115 0.113 0.113

0.404 0.430 0.430

0.2850.340 0.340

0.330

0.397 0.397

0.032

0.038 0.058

0.0260.020

0.015

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1990 (Calculated) 2003 (Calculated) 2003 (WV & DE Reported)

(million s

epti

c sy

stem

s)

NY PA MD VA WV DE

• WV reported systems are 52% above what is calculated. • DE reported systems are 29% above what is calculated. • Press reports 460K septic system in MD – compared to 340K systems calculated. • No current system data from NY, PA, MD, and VA.


0.115 0.113 0.113 0.113

0.404 0.430 0.430 0.405

0.2850.340 0.340

0.329

0.330

0.397 0.3970.397

0.032

0.038 0.0580.058

0.0260.0260.020

0.015

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1990 (Calculated) 2003 (Calculated) 2003 (WV & DE Reported) 2003 (After SepticConnection BMP)

(million s

epti

c sy

stem

s)

NY PA MD VA WV DE

• The septic connection BMP reduces the calculated number of systems.

Tributary Strategy WorkgroupDiscussion of Phase 5 Watershed Model

Jeff SweeneyUniversity of Maryland

Chesapeake Bay Program [email protected]

410-267-9844http://www.chesapeakebay.net/

Tributary Strategy Workgroup Phase 5 MeetingChesapeake Bay Program Office

January 26, 2005

tributary strategy workgroup discussion of phase 5 watershed model

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