                                                           File: UPDATE.TXT


                    WASP Model System Update Notes

            Center for Exposure Assessment Modeling (CEAM)
                 U.S. Environmental Protection Agency
               Office of Research and Development (ORD)
                  Environmental Research Laboratory
                       960 College Station Road
                     Athens, Georgia  30605-2720

                             706/546-3549



-----------------------------------------------------------------------------

The following are explanations of undocumented changes in the WASP4 modeling
system since the publishing of the WASP4 User's manual.  A brief explanation
and example are given for each change/enhancement. 

Changes in WASP4 
~~~~~~~~~~~~~~~~ 
I.   Modified the model time step optimizer.  If the user selects the
automatic time step optimizer, the model time step entered is considered the
largest time step possible.

II.  As of release 3.0 the format for line 4 has changed.  Note changes and
make corrections to pre-existing input data set files.

     KSIM is no longer needed as the steady state solution technique and is
not incorporated into the WASP model at this time.  This causes all the data
on line 4 to shift to the left 5 spaces.  Also removed from this line is the
system and segments to display at run time.  This information is required on
a new line that is inserted between line 4 and 5.  WASP allows the user to
designate 6 segments to have simulation results displayed at run time.
During execution the user has the option to change the display segments.
Note that if the user does not enter any information the model will prompt
the user for the segment numbers to display (pick list style).

TEST 5-LAYER LAKE 
SIMPLE EUTROPHICATION PROBLEM 
 NSEG NSYS ICRD MFLG IDMP NSLN INTY ADFC   DD HHMM       A:MODEL OPTIONS 
   05   08    0    1    1    0    1  0.0    1 0000    0.00
    1    2    3    4    5    0  <====THIS LINE IS NEW TO VERSION 3.0
    1 
      2.00       15. 
    4 
  1.5       15.       2.0       10.       4.0       14.       7.0      28. 
    0    0    0    0    0    0    0    0 

     INTY is the time step optimizer flag: 0 = the user will supply the time
step, 1 = WASP4 will calculate the time step.  If the user selects to use the
optimizer, the user is required to supply the highest value for the time step
on line 6, first entry.  In this example, the time step optimizer will be
used and a maximum time step of 2 days has been designated.

     A salinity environmental time function has been added to the
eutrophication program.  This allows the user to vary the salinity
concentration within segments over time.  WASP uses this information to
calculate dissolved oxygen saturation values.  The salinity time function
works the same as all others -- the time function value is multiplied by the
segment parameter value that was entered for salinity.  The salinity
environmental time function has been assigned time function number 20.

     An environmental time function has been added to the EUTRO4 program,
ice cover.  This function is designated by time function number 22 and its
purpose is to adjust the available water surface area for which reaeration 
can occur.  The value entered should be the percentage of the surface area
free of ice cover.  Note that the default value is 1.00 (100%).

     NOTE: For release of WASP 4.20, the Time Function inputs are as
           described in the WASP4 manual (pages 186 and 196). 
     
     There has been an additional flow option (IQOPT) added to WASP4.  Based
on the request of a WASP user, a flow option based upon individual flows, not
flows across a segment interface, has been implemented.  This was done to
mimic large scale circulation flow patterns in water bodies such as lakes.
This option moves mass based on individual flow patterns as was done in
WASP3.  WASP4 flow option calculates a net flow before moving mass, causing
mass to be moved in only one direction across an interface during each time
step.


IQOPT Options
~~~~~~~~~~~~~
                     IQOPT = 1  Mass moves based on Net Flow 
                     IQOPT = 2  Mass moves with individually described  
                                flow patterns 
                     IQOPT = 3  Linkage to Hydrodynamic Model 
      
     NOTE:  There is only one option for hydrodynamic linkage (Formatted
            Sequential). 
      
     Two new segment parameters have been added to the EUTRO4 program.  They
are:  SODTA parameter number 12 and ITOTLIM 13.  SODTA is the temperature
adjustment coefficient (theta) for calculating sediment oxygen demand.  The
default value is 1.0.


WASP4-DYNHYD 5.xx Linkage Input
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     Because of the extensive revisions to the WASP4-DYNHYD 5.0 linkage
routines, it has become necessary to alter the input data set.  When linking
WASP with DYNHYD, the user must specify the following: 
      
    3    1    +    *    +    *    +    *    +    *    +    *    D: FLOWS 
    0    0    0    0    0    0    0    0 
      
     Specify flow option 3 (IQOPT=3) in the first line of data group D,
then skip to the next flow field (i.e., Pore Water, Sediment Movement) and
with flow bypass options.  For linked water column flows only, the resulting
data set is illustrated above.  There is no need for additional data as it is
supplied by the hydrodynamic interface file.


Changes in EUTRO4 Reaeration
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     Because of insensitivity of wind driven reaeration algorithms at low
wind speeds, the wind reaeration routines have been replaced by O'Connor's
(1983) algorithm.  See encode documentation for citation.  Because of these
changes, some additional user specified information is required.  The user
will need to add a constant 1 to card group H specifying water body type:

              Wtype     1        1   Small System (Laboratory Scale)
                                 2   Medium System (Lake)
                                 3   Large (Estuary)

     NOTE:  The default value is 3 if one is not specified.

     An environmental time function has been added to specify air
temperature.  This time function is number 21 and is entered in the same
manner as the others.  If the user does not specify an air temperature, the
program will stop executing and prompt the user for a temperature that will
be constant.  If a water temperature is specified as zero degrees, the water
body is considered to be covered by ice and no reaeration is calculated.

     A segment parameter REARSG (13) has been added to allow the user to
specify a segment specific reaeration coefficient.  If no segment specific
coefficient is added, the model will calculate one or use the constant K2.

     A segment specific zooplankton ZOOSG(15) parameter has been added to
control the zooplankton grazing rate on a segment by segment basis.

     A segment specific light interception (canopy shading) ITOTSG (13)
parameter has been added to adjust incoming solar radiation on a segment by
segment basis.

      
Changes in DYNHYD
~~~~~~~~~~~~~~~~~
     Several improvements have been made to the DYNHYD model.

     1)  The WASP4-DYNHYD linkage has been completely rewritten in order to
         make the linkage less cumbersome for model users.
     2)  The model has been modified to accommodate trapezoidal channels as
         well as rectangular channels.
     3)  Evaporation and precipitation have been added.

     With these improvements, it became necessary to alter the model's input
data structure.


DYNHYD Input Changes
~~~~~~~~~~~~~~~~~~~~
    DYNHYD EXAMPLE 
    COMPLEXITY 1: RIVER; CONSTANT INFLOWS, CONSTANT WIND, NO TIDE 
  ***** PROGRAM CONTROL DATA ************************************** 
     13   13 0000 30.0    5    1 0630    3 1230 
  ***** OUTPUT CONTROL DATA *************************************** 
         0.0      12.0   13 
      1    2    3    4    5    6    7    8    9   10   11   12   13 
  ***** SUMMARY CONTROL DATA ************************************** 
      1    1 0630 12.5   10    5  
                         ~~    ~ 
                         (b)  (a) 
      
     The 5 (a) in the Summary Control Data Group will cause DYNHYD to write
information to the scratch file every five time steps.  If the users does not
enter a value here, DYNHYD will write to the scratch file every time step.
This value has to be evenly divided into NODYN (b) for the averaging routines
to work properly.  If the user does not enter an evenly divisible number,
DYNHYD will adjust the number until it is so. 


Junction Geometry Input Data
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     Record 1  -- Data Group Identification (A80)

     Record 2 --  Number of junctions with Variable Surface Area (I5)

                  IJ  =  Number of Junctions with variable surface areas

     Record 3 --  Junction Geometry Data (JJ,SAN(JJ)) (I5, F10.0)

                  JJ = Junction Number (I5)

                  SAN (JJ) = Ratio of change in surface area with respect to
                             surface elevation (F10.0)

                        ORGANIZATION OF RECORDS

     Record 1 and 2 are entered once.  Record 3 is entered IJ times.


Channel Geometry Input Data
~~~~~~~~~~~~~~~~~~~~~~~~~~~
     Record 1  -- Data Group Identification (A80)

     Record 2 --  Number of Channels with Variable Width (I5)

                  IC  =  Number of Channels with variable width

     Record 3 --  Channel Geometry Data (I5,F10.0)

                  ICC =  Channel Number (I5)

          SLOPE (ICC) =  Ratio of change in channel width with respect to
                         change in HEAD (F10.0).  Note:  A value of zero
                         implies a rectangular channel.

                        ORGANIZATION OF RECORDS

     Record 1 and 2 are entered once.  Record 3 is entered ICC times.


Precipitation/Evaporation Input
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 **** PRECIPITATION OR EVAPORATION DATA *********************************** 
      8  .1157E-6   1.00E00
      1 0000     5000.    1 0100     5000.    1 0200     6000.    1 0300
  3000.
      1 0400     0000.    1 0500     0000.    1 0600     5000.    1 0800
  5000.


     Record 1 -- Data Group Identification Header (A80)

     Record 2 -- Input Data description (I5, 2F10.0)

                 NOEVA -- Number of Precipitation Data Points (I5)

                 SCALE -- Scale Factor (F10.0)

                 CONVE -- Units Conversion Factor (F10.0)

     Record 3 -- Precipitation/Evaporation Time Function
                 (4(F5.0,1X,2F2.0,F10.0))

                 DAY(K)  -- Day corresponding to rainfall event

                 HR(K)   -- Hour corresponding to rainfall event

                 MIN(K)  -- Minute corresponding to rainfall event

                 EVAP(K) -- Precipitation/Evaporation Rate (M/SEC) for
                            corresponding DAY(K),HR(K),MIN(K).  If rainfall
                            units are cm/day or cm/year the conversion
                            factors are 1.157E-7 and 3.17E-10.

                 NOTE: Precipitation is positive, Evaporation is negative.

                            K = 1 to NOEVA 

                        ORGANIZATION OF RECORDS 
       
     Record 1 and 2 are entered once.  For record 3, four sets of data can be
     entered per line.  If NOEVA = 0, skip to segment mapping.


WASP4 Junction to Segment Map
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 ***** MAP TO WASP4  *******************************************************
    0   13
    1    0
    2    1
    3    2
    4    3
    5    4
    6    5
    7    6
    8    7
    9    8
   10    9
   11   10
   12   11
   13    0

     Record 1 -- Data Group Identification Header (A80) 

     Record 2 -- Time variant/invariant segment depth & velocity switch (I5)

                 HDEPVEL  -- Controls the writing of information to the
                             interfacial hydrodynamic file for WASP.

                       0  -- DYNHYD will write time variant segment velocities
                             and depths for WASP.

                       1  -- DYNHYD will write one set of segment velocities
                             and depths for WASP to read.  Note:  This option
                             should be used in situations where depth and
                             velocity are NOT changing radically.

     Record 2 -- Number of Junctions to map to WASP4


     Record -- 3 to Number of Junctions to Map (J)

                  JUNSEG(J) = Junction number to map out for WASP input.

                  WASPSEG(j)= WASP segment to receive the flow data from
                              JUNSEG.

     This option allows the user to map portions of the DYNHYD output for
WASP.
