United States Office of Water EPA-823-R-99-003
Environmental Protection 4305 March 1999
Agency Updated 4/2007
&EPA BASINS Technical Note 3
WinHSPF Simulation Module Matrix
-------
Technical Note 3
WinHSPF Simulation Module Matrix
March 31,2007
The BASINS' GIS and Windows interface to the Hydrologic Simulation Program Fortran
(WinHSPF), is a flexible watershed simulation model that permits users to simulate a large
number of pollutants over a range of simplistic to complex formulations. The HSPF program has a
modular structure in which pervious and impervious land segments define the first two modules,
and free flowing reaches and reservoirs define the third. Each module contains specialized
algorithms, or sections, for simulating the environmental fate processes important to a particular
pollutant or group of pollutants (e.g. the pesticide section simulates absorption/desorption and
volatilization). While all modules and sections can be selected, the typical model simulation
requires only a limited selection. Additionally, however, some sections are dependent on output
from other modules and WinHSPF will not function with an improper combination of sections
selected. Also, by starting simple and gradually building the model's complexity, a user increases
their ability to trap errors and will thus reduce the time required to build a functioning, complex
HSPF simulation. Finally, some sections need not be simulated as long as the user can supply a
time-series of data for the output from that section. This technical note, then, is meant to answer
the following two key questions: 1) What is the minimum necessary set of modules and sections for
modeling my pollutant of concern; and 2) In what order should I add modules such that I can
slowly build the complexity of my model?
The matrix (see Figure 1, below) shows the hydrologic process or pollutant to be simulated
along the top, and the HSPF modules and sections along the left. A set of notes, at the end,
provides additional details about the conditions under which a section is required, recommended,
or optional. To read the matrix, select the process or pollutant you wish to model, and read down
that column to determine which HSPF sections you must simulate as well as those which are
recommended or optional. For example, to simulate pesticides, reading down the column in the
PERLND block, shows ATEMP and SNOW as optional (only necessary if snow is significant in
your watershed), PWATER and SEDMNT as required, PSTEMP as only necessary if first-order
adsorption-desorption is selected, and MSTLAY (soil moisture storage and fluxes) and PEST (by
definition) as required. Reading down the pesticide column in the RCHRES module, HYDR and
ADCALC are required, HTRCH is recommended, SEDTRN is recommended to account for
reduced photolysis due to sediment shading (and is required if the pesticide is sediment associated)
and GQUAL is required. While HSPF does not simulate pesticide application or fate and transport
on impervious land segments, you still need to model the simulation elements that will effect
quantities in the receiving water body: i.e. ATEMP and SNOW (if simulated in the PERLND
module), IWATER (for hydrology), IWTGAS (for temperature if HTRCH selected in RCHRES
module) and SOLIDS (if SEDTRN selected in RCHRES).
Page 2 of9
-------
Note, each module (Pervious Land [PERLND], Impervious Land [IMPLND], and Free Flowing
Reach or Reservoir [RCHRES]) is essentially its own separate matrix since they can each be run
independently of the others (e.g. running general water quality constituent simulations in a
RCFIRES segment does not require a constituent load from either a PERLND or IMPLND;
similarly, modeling nutrient washoff in a PERLND does not require you to route the runoff to a
RCHRES segment).
HSPF Stcticri
% Lam ^
'* ^ "fa'*.
*: .S**'S&
/ ' j Options
ATE^P
, SNOW
1
SE0MNT
! PST6MP
§ . PWT5AS
U PQUAL
MSTLAV
PEST
NITR
PUGS
TRACER
AT6MP
1 -
i SNOW
g fWATER
ol SOLIDS
IWT6AS
IQUAL
A
&
*s*
-
W*j£F4&f i ^ ! y3
J *,*
*
...
1
1
^ ' K al^^ as-fiw« §3^ sisMltmf n
*
M=Wf
K !.«»
swia
G"" ,T
* ^ j" " 1 * A !
," «,
o !T'»"'i> 'v« *7v^ ?-r~i,-i"
s i
i ' *!*'*
=K ,m^,h»,«.,::.B.1^»»mu«(0
Figure 1. Matrix of HSPF Sections Required vs. Pollutants and Processes Modeled
Page 3 of9
-------
Table Notes:
PERLND
Adjusted Air Temp
ATEMP (required)
Snow
ATEMP (recommended)
SNOW (required)
Basic Hydrology
ATEMP (optional)
SNOW (optional)
PWATER (required)
Soil Erosion
ATEMP (optional)
SNOW (optional)
PWATER (required)
SEDMNT (required)
Soil Temperature
ATEMP (recommended)
PSTEMP (required)
by definition; used to adjust for air temperature differences between
meteorologic station and site due to elevation differences (HSPF uses lapse
rate that varies between 0.0035 and 0.005 degrees-F/ft)
can be bypassed, in HSPF by adjusting gage temperature directly
(required in HSPF if SNOW simulated).
by definition
results used only if SNOW is simulated (required in HSPF if
SNOW is simulated)
only needed in regions where snow is significant in the hydrologic cycle
by definition
results used only if SNOW is simulated
(required in HSPF if SNOW simulated)
only needed in regions where snow is significant hydrologic
cycle component
surface quantities SURO and SURS used in SEDMNT routine
by definition
can be bypassed, in HSPF by adjusting gage temperature
directly
by definition
Page 4 of 9
-------
Water Temperature, Dissolved Oxygen, Dissolved CO2
ATEMP (recommended) results used only if SNOW or PSTEMP simulated
SNOW (optional) only needed in regions where snow is significant hydrologic cycle
component
PWATER (required) runoff components SURO, IFWO, AGWO are the key simulation
elements
PSTEMP (recommended) observed/estimated soil temps may be input instead
PWTGAS (required) by definition
General WQ
ATEMP (optional)
SNOW (optional)
PWATER (required)
SEDMNT (required)
PQUAL (required)
results used only if snow is simulated
only needed in regions where snow is significant hydrologic cycle
component
surface quantities SURO and SURS used in SEDMNT routine
only needed if water quality constituent is sediment-associated
by definition
Pesticides
ATEMP (recommended)
SNOW (optional)
PWATER (required)
SEDMNT (required)
PSTEMP (recommended)
MSTLAY (required)
PEST (required)
results used only if SNOW or PSTEMP simulated
(required in HSPF if SNOW simulated)
only needed in regions where snow is significant hydrologic cycle
component
soil moisture fluxes/storages are the key simulation elements
soil erosion must be simulated
observed/estimated soil temps may be input directly in HSPF
leaching factors must be simulated
by definition
Nitrogen
ATEMP (recommended)
SNOW (optional)
PWATER (required)
SEDMNT (required)
PSTEMP (recommended)
MSTLAY (required)
NITR (required)
results used only if SNOW or PSTEMP simulated
(required in HSPF if SNOW simulated)
only needed in regions where snow is significant hydrologic cycle
component
soil moisture fluxes/storages must be simulated
soil erosion must be simulated
observed/estimated soil temps may be input directly in HSPF
leaching factors must be simulated
by definition
Page 5 of 9
-------
Phosphorus
ATEMP (recommended)
SNOW (optional)
PWATER (required)
SEDMNT (required)
PSTEMP (recommended)
MSTLAY (required)
PHOS (required)
Tracer
ATEMP (optional)
SNOW (optional)
PWATER (required)
MSTLAY (required)
TRACER (required)
results used only if SNOW or PSTEMP simulated
(required in HSPF if SNOW simulated)
only needed in regions where snow is significant hydrologic cycle
component
soil moisture fluxes/storages must be simulated
soil erosion must be simulated
observed/estimated soil temps may be input directly in HSPF
leaching factors must be simulated
by definition
results used only if SNOW is simulated
only needed in regions where snow is significant hydrologic cycle
component
soil moisture fluxes/storages must be simulated
leaching factors must be simulated
by definition
Page 6 of 9
-------
IMPLND
Adjusted Air Temp
ATEMP (required) by definition; used to adjust for air temperature differences between
meteorologic station and site due to elevation differences
Snow
ATEMP (recommended) can be bypassed, in HSPF by adjusting gage temperature directly
(required in HSPF if SNOW is simulated)
SNOW (required)
Basic Hydrology
ATEMP (optional)
SNOW (optional)
IWATER (required)
Solids
ATEMP (optional)
SNOW (optional)
IWATER (required)
SOLIDS (required)
by definition
results used only if SNOW is simulated (required in HSPF if SNOW is
simulated)
only needed in regions where snow is significant hydrologic cycle
component
by definition
results used only if SNOW is simulated (required in HSPF if SNOW is
simulated)
only needed in regions where snow is significant hydrologic cycle
component
surface runoff must be simulated
by definition
Water Temperature, Dissolved Oxygen, Dissolved CO2
ATEMP (recommended) can be bypassed, in HSPF by adjusting gage temperature directly
(required in HSPF if SNOW is simulated)
only needed in regions where snow is significant hydrologic cycle
component
surface runoff must be simulated
by definition
SNOW (optional)
IWATER (required)
IWTGAS (required)
General WQ
ATEMP (optional)
SNOW (optional)
IWATER (required)
SOLIDS (required)
IQUAL (required)
results used only if SNOW is simulated (required in HSPF if SNOW is
simulated)
only needed in regions where snow is significant hydrologic cycle
component
surface runoff must be simulated
only needed if water quality constituent is sediment associated
by definition
Page 7 of 9
-------
RCHRES
Flow Routing
HYDR (required)
Conservative Substance
HYDR (required)
ADCALC (required)
Water Temperature
HYDR (required)
ADCALC (required)
HTRCH (recommended)
Sediment Transport
HYDR (required)
ADCALC (required)
HTRCH (recommended)
SEDTRN (required)
General WQ, Pesticides
HYDR (required)
ADCALC (required)
HTRCH (recommended)
SEDTRN (recommended)
GQUAL (required)
by definition
flow routing must be simulated
transport factors must be simulated
flow routing must be simulated
transport factors must be simulated
by definition
flow routing must be simulated
transport factors must be simulated
required only if Toffaletti or Colby methods are used for sand, can be
bypassed by inputting water temperature directly in HSPF
by definition
flow routing must be simulated
transport factors must be simulated
can be bypassed by inputting water temperature directly in HSPF
only required if sediment associated, otherwise is optional;
recommended if photolsis is considered (to account for sediment
shading); can be bypassed by inputting sediment concentration
directly in HSPF
by definition
Page 8 of 9
-------
Dissolved Oxygen, BOD
HYDR (required)
ADCALC (required)
HTRCH (recommended)
SEDTRN (optional)
OXRX (required)
NUTRX (optional)
PLANK (optional)
flow routing must be simulated
transport factors must be simulated
can be bypassed by inputting water temperature directly
only if NUTRX used
by definition
nutrients usually important
plankton usually important
Inorganic Phosphorus, Inorganic Nitrogen
HYDR (required)
ADCALC (required)
HTRCH (recommended)
SEDTRN (required)
OXRX (required)
NUTRX (required)
PLANK (optional)
flow routing must be simulated
transport factors must be simulated
can be bypassed by inputting water temperature directly
phosphate and ammonia absorption usually important
DO and BOD must be simulated
by definition
plankton usually important
Benthic Algae, Phytoplankton, Zooplankton, and Organic C, N, and P
HYDR (required)
ADCALC (required)
HTRCH (recommended)
SEDTRN (recommended)
OXRX (required)
NUTRX (required)
PLANK (optional)
flow routing must be simulated
transport factors must be simulated
can be bypassed by inputting water temperature directly
can be bypassed by inputting sediment concentration directly (unless
already needed by NUTRX)
DO and BOD must be simulated
nutrients must be simulated
by definition
PH, Carbon Dioxide, Total Inorganic Carbon
HYDR (required)
ADCALC (required)
CONS (recommended)
HTRCH (recommended)
SEDTRN (recommended)
OXRX (required)
NUTRX (required)
PLANK (required)
PHCARB (required)
flow routing must be simulated
transport factors must be simulated
can be bypassed by inputting alkalinity concentrations directly
can be bypassed by inputting water temperature directly
only if needed by NUTRX
DO and BOD must be simulated
nutrients must be simulated
plankton CO2 fluxes must be simulated
by definition
Page 9 of 9
------- |