Phase V Watershed Model

• We have 1994-2000 flows, revised March 2006. Used to drive CH3D

• We have May 2006 Phase V loads for WQM.

• Revisions to Phase V loads are possible

Phase IV.3 Loads

Phase V Loads

Phase IV.3 Loads

Phase V Loads

Phase IV.3 Loads

Phase V Loads

Phase IV.3 Loads

Phase V Loads

Phase IV.3 Loads

Phase V Loads

Conclusions• Total nitrogen and phosphorus loads appear to

go down

• Tributaries are more sensitive than main bay. Changes largely in most upstream stations

• Scatter is reduced for nitrogen and phosphorus

• No consistent difference for solids

• No fundamental change in calibration status

Sub-Grid-Scale SAV Model

For every model cell, we have the following area increments:

•< 0.5 m

•0.5 m < d < 1 m

•1 m < d < 1.5 m

•1.5 m < d < 2 m

Keeping track of these areas and the SAV within will allow us to compute SAV area and compare to CBP data base

Status

• We will complete detailed examination of SAV in four key segments, one for each species.

• We will look at annual areas for total and ten largest segments

• SAV is currently implemented for one species, Vallisneria, everywhere. We need to tune and incorporate two more species

CBP criteria for SAV survival is optical depth less than 1.6 to 2

Optical Model

• Model developed by Charles Gallegos, SERC

• Rigorous calculation of diffuse light attenuation based on inherent optical properties of color, total suspended solids, chlorophyll

• Parameter set from this study and other CBP-sponsored efforts

Optical Model

• Parameter set varies seasonally and, potentially, in 78 CBPS

• A good deal of judgment was involved in parameter assignment when observations were unavailable.

• The calculation is enormously time-consuming. Chuck created a 2,000,000 element look-up table that is incorporated in our model.

Old Attenuation Model

New Attenuation Model

Old Attenuation Model

New Attenuation Model

Old Attenuation Model

New Attenuation Model

Estuarine Phosphorus Model

• Initial coding of PIP in water quality model

• PIP assumed to be completely inert

• Behaves as TSS

Sa n d-si ze

Ex ch . P

R efrac to r y P

Silt /C lay-siz e

E xch . P

R efr acto ry P

R esu sp en d ed

E xch . P

R efr acto ry P

D iss ol ved

P h o sp h ate

R efr acto ryP artic u late

O rg an icP h os p h or u s

L a b ilePa rticu late

Or g an icPh o sp h o ru s

D isso lv edO rg an ic

P h o sp h or u s

Sediments

T w oZ o o pl an kto n

G ro u p s

T h r ee A lg alG ro u p s

m in er aliz atio n

h yd ro lysis

p re da tio n

resp ir atio n

min

eral

izat

ion u

pta

ke

Se ttlin g a nd res u sp en sio n

P articulate Ino rganic P

E xtern al L o ad in g

D O P Up take ?

Sa n d-si ze

Ex ch . P

R efrac to r y P

Silt /C lay-siz e

E xch . P

R efr acto ry P

R esu sp en d ed

E xch . P

R efr acto ry P

D iss ol ved

P h o sp h ate

R efr acto ryP artic u late

O rg an icP h os p h or u s

R efr acto ryP artic u late

O rg an icP h os p h or u s

L a b ilePa rticu late

Or g an icPh o sp h o ru s

L a b ilePa rticu late

Or g an icPh o sp h o ru s

D isso lv edO rg an ic

P h o sp h or u s

Sediments

T w oZ o o pl an kto n

G ro u p s

T h r ee A lg alG ro u p s

T h r ee A lg alG ro u p s

m in er aliz atio n

h yd ro lysis

p re da tio n

resp ir atio n

min

eral

izat

ion u

pta

ke

Se ttlin g a nd res u sp en sio n

P articulate Ino rganic P

E xtern al L o ad in g

D O P Up take ?

70% of Choptank PP is PIP

47% of Potomac PP is PIP

58% of Susquehanna PP is PIP

62% of Patuxent PP is PIP

With PIP

No PIP

With PIP

No PIP