C     Last change:  AWH  30 May 2000
      SUBROUTINE GWF1BCF6AL(ISUM,LCSC1,LCHY,LCSC2,LCTRPY,ITRSS,ISS,
     1  IN,NCOL,NROW,NLAY,IOUT,IBCFCB,LCWETD,IWDFLG,LCCVWD,
     2  WETFCT,IWETIT,IHDWET,HDRY,IAPART,IFREFM,LAYHDT)
C
C-----VERSION 11JAN2000 GWF1BCF6AL
C     ******************************************************************
C     ALLOCATE ARRAY STORAGE FOR BLOCK-CENTERED FLOW PACKAGE
C     ******************************************************************
C
C        SPECIFICATIONS:
C     ------------------------------------------------------------------
      DIMENSION LAYHDT(NLAY)
      COMMON /BCFCOM/LAYCON(200)
      COMMON /FLWAVG/LAYAVG(200)
      CHARACTER*12 AVGNAM(4)
      DATA AVGNAM/'HARMONIC    ','ARITHMETIC  ',
     1            'LOGARITHMIC ','*UNCONFINED*'/
C     ------------------------------------------------------------------
C
C1------IDENTIFY PACKAGE
      WRITE(IOUT,1) IN
    1 FORMAT(1X,/1X,'BCF6 -- BLOCK-CENTERED FLOW PACKAGE, VERSION 6',
     1', 1/11/2000',/,9X,'INPUT READ FROM UNIT',I3)
C
C2------READ AND PRINT IBCFCB (FLAG FOR PRINTING
C2------OR UNIT# FOR RECORDING CELL-BY-CELL FLOW TERMS), HDRY
C2------(HEAD AT CELLS THAT CONVERT TO DRY), AND WETTING PARAMETERS.
      IF(IFREFM.EQ.0) THEN
         READ(IN,'(I10,F10.0,I10,F10.0,2I10)')
     1              IBCFCB,HDRY,IWDFLG,WETFCT,IWETIT,IHDWET
      ELSE
         READ(IN,*) IBCFCB,HDRY,IWDFLG,WETFCT,IWETIT,IHDWET
      END IF
C
C2A-----DETERMINE ISS FROM ISSFLG
      IF(ITRSS.EQ.0) THEN
         ISS=1
      ELSE
         ISS=0
      END IF
C
C2B-----PRINT VALUES
      IF(ISS.EQ.0) WRITE(IOUT,3)
    3 FORMAT(1X,'TRANSIENT SIMULATION')
      IF(ISS.NE.0) WRITE(IOUT,4)
    4 FORMAT(1X,'STEADY-STATE SIMULATION')
      IF(IBCFCB.LT.0) WRITE(IOUT,8)
    8 FORMAT(1X,'CONSTANT-HEAD CELL-BY-CELL FLOWS WILL BE PRINTED',
     1     ' WHEN ICBCFL IS NOT 0')
      IF(IBCFCB.GT.0) WRITE(IOUT,9) IBCFCB
    9 FORMAT(1X,'CELL-BY-CELL FLOWS WILL BE SAVED ON UNIT',I3)
      WRITE(IOUT,11) HDRY
   11 FORMAT(1X,'HEAD AT CELLS THAT CONVERT TO DRY=',G13.5)
      IF(IWDFLG.NE.0) GO TO 35
      WRITE(IOUT,12)
   12 FORMAT(1X,'WETTING CAPABILITY IS NOT ACTIVE')
      GO TO 39
C
   35 WRITE(IOUT,36)
   36 FORMAT(1X,'WETTING CAPABILITY IS ACTIVE')
      IF(IWETIT.LE.0) IWETIT=1
      WRITE(IOUT,37)WETFCT,IWETIT
   37 FORMAT(1X,'WETTING FACTOR=',F10.5,
     1     '     WETTING ITERATION INTERVAL=',I4)
      WRITE(IOUT,38)IHDWET
   38 FORMAT(1X,'FLAG THAT SPECIFIES THE EQUATION TO USE FOR HEAD',
     1    ' AT WETTED CELLS=',I4)
C
C3------STOP THE SIMULATION IF THERE ARE MORE THAN 200 LAYERS.
   39 IF(NLAY.LE.200) GO TO 50
      WRITE(IOUT,41)
   41 FORMAT(1X,/1X,'YOU HAVE SPECIFIED MORE THAN 200 MODEL LAYERS'/1X,
     1 'SPACE IS RESERVED FOR A MAXIMUM OF 200 LAYERS IN ARRAYS LAYCON',
     2 ' AND LAYAVG')
      STOP
C
C4------READ LAYCON & PRINT TITLE FOR LAYCON TABLE.
   50 IF(IFREFM.EQ.0) THEN
         READ(IN,'(40I2)') (LAYCON(I),I=1,NLAY)
      ELSE
         READ(IN,*) (LAYCON(I),I=1,NLAY)
      END IF
      WRITE(IOUT,52)
   52 FORMAT(1X,5X,'LAYER  LAYER-TYPE CODE     INTERBLOCK T',
     1      /1X,5X,44('-'))
C
C5------LOOP THROUGH LAYERS CALCULATING LAYAVG, PRINTING THE LAYER-TYPE
C5------CODE, AND COUNTING LAYERS THAT NEED TOP & BOT ARRAYS.
      NBOT=0
      NTOP=0
      DO 100 I=1,NLAY
      IF(LAYCON(I).EQ.30 .OR. LAYCON(I).EQ.32) LAYCON(I)=LAYCON(I)-10
      INAM=LAYCON(I)/10
      LAYAVG(I)=INAM*10
      IF(LAYAVG(I).LT.0 .OR. LAYAVG(I).GT.30) THEN
         WRITE(IOUT,53) LAYAVG(I)
   53    FORMAT(1X,'INVALID INTERBLOCK T CODE:',I4)
         STOP
      END IF
      LAYCON(I)=LAYCON(I)-LAYAVG(I)
      L=LAYCON(I)
      INAM=INAM+1
      WRITE(IOUT,55) I,L,LAYAVG(I),AVGNAM(INAM)
   55 FORMAT(1X,I9,I13,I11,' -- ',A)
      IF(LAYCON(I).LT.0 .OR. LAYCON(I).GT.3) THEN
         WRITE(IOUT,56) LAYCON(I)
   56    FORMAT(1X,'INVALID LAYER TYPE:',I4)
         STOP
      END IF
C
C     SET GLOBAL HEAD-DEPENDENT THICKNESS INDICATOR
      IF (L.EQ.0 .OR. L.EQ.2) THEN
        LAYHDT(I)=0
      ELSEIF (L.EQ.1 .OR. L.EQ.3) THEN
        LAYHDT(I)=1
      ENDIF
C
C5A-----ONLY THE TOP LAYER CAN BE UNCONFINED(LAYCON=1).
      IF(L.NE.1 .OR. I.EQ.1) GO TO 70
      WRITE(IOUT,57)
   57 FORMAT(1X,/1X,'LAYER TYPE 1 IS ONLY ALLOWED IN TOP LAYER')
      STOP
C
C5B-----LAYER TYPES 1 AND 3 NEED A BOTTOM. ADD 1 TO KB.
   70 IF(L.EQ.1 .OR. L.EQ.3) NBOT=NBOT+1
C
C5C-----LAYER TYPES 2 AND 3 NEED A TOP. ADD 1 TO KT.
      IF(L.EQ.2 .OR. L.EQ.3) NTOP=NTOP+1
C
C5D-----IF LAYAVG=30, BUFF MUST BE SEPARATE FROM RHS (IAPART NOT 0).
      IF(IAPART.EQ.0 .AND. LAYAVG(I).EQ.30) THEN
         WRITE(IOUT,75)
   75    FORMAT(1X,'IAPART IN BAS PACKAGE MUST BE NONZERO',
     1      ' WHEN INTERBLOCK T IS *UNCONFINED*')
         STOP
      END IF
  100 CONTINUE
C
C
C6------COMPUTE THE NUMBER OF CELLS IN THE ENTIRE GRID AND IN ONE LAYER.
      NRC=NROW*NCOL
      ISIZ=NRC*NLAY
C
C7------ALLOCATE SPACE FOR ARRAYS.  MAKE SURE THE LAST ALLOCATION
C7------INCLUDES SPACE FOR ALL LAYERS EVEN IF NOT USED SO THAT THE
C7------THE DIMENSIONED SIZE OF THE ARRAYS IN THE OTHER MODULES NEVER
C7------EXCEEDS THE ALLOCATED SPACE IN X.
      ISOLD=ISUM
      LCSC2=ISUM
      IF(ISS.EQ.0) ISUM=ISUM+NRC*NTOP
      LCTRPY=ISUM
      ISUM=ISUM+NLAY
      LCWETD=ISUM
      IF(IWDFLG.NE.0) ISUM=ISUM+NRC*NBOT
      IF(ISS.EQ.0) THEN
         LCHY=ISUM
         ISUM=ISUM+NRC*NBOT
         LCCVWD=ISUM
         IF(IWDFLG.NE.0) ISUM=ISUM+NRC*(NLAY-1)
         LCSC1=ISUM
         ISUM=ISUM+ISIZ
      ELSE IF(IWDFLG.NE.0) THEN
         LCSC1=ISUM
         LCHY=ISUM
         ISUM=ISUM+NRC*NBOT
         LCCVWD=ISUM
         ISUM=ISUM+ISIZ
      ELSE
         LCCVWD=ISUM
         LCSC1=ISUM
         LCHY=ISUM
         ISUM=ISUM+ISIZ
      END IF
C
C8------PRINT THE AMOUNT OF SPACE USED BY THE BCF PACKAGE.
      ISP=ISUM-ISOLD
      WRITE(IOUT,101) ISP
  101 FORMAT(1X,I10,' ELEMENTS IN RX ARRAY ARE USED BY BCF')
C
C9------RETURN.
      RETURN
      END
      SUBROUTINE GWF1BCF6RP(IBOUND,HNEW,SC1,HY,CR,CC,CV,DELR,DELC,
     1 SC2,TRPY,IN,ISS,NCOL,NROW,NLAY,IOUT,WETDRY,IWDFLG,CVWD)
C
C-----VERSION 11JAN2000 GWF1BCF6RP
C     ******************************************************************
C     READ AND INITIALIZE DATA FOR BLOCK-CENTERED FLOW PACKAGE
C     ******************************************************************
C
C        SPECIFICATIONS:
C     ------------------------------------------------------------------
      CHARACTER*24 ANAME(7)
      DOUBLE PRECISION HNEW
C
      DIMENSION HNEW(NCOL,NROW,NLAY),SC1(NCOL,NROW,NLAY),
     1    HY(NCOL,NROW,NLAY),CR(NCOL,NROW,NLAY),CC(NCOL,NROW,NLAY),
     2    CV(NCOL,NROW,NLAY),DELR(NCOL),DELC(NROW),SC2(NCOL,NROW,NLAY),
     3    TRPY(NLAY),IBOUND(NCOL,NROW,NLAY),
     4    WETDRY(NCOL,NROW,NLAY),CVWD(NCOL,NROW,NLAY)
C
      COMMON /BCFCOM/LAYCON(200)
C
      DATA ANAME(1) /'    PRIMARY STORAGE COEF'/
      DATA ANAME(2) /'    TRANSMIS. ALONG ROWS'/
      DATA ANAME(3) /'   HYD. COND. ALONG ROWS'/
      DATA ANAME(4) /'VERT HYD COND /THICKNESS'/
      DATA ANAME(5) /'  SECONDARY STORAGE COEF'/
      DATA ANAME(6) /'COLUMN TO ROW ANISOTROPY'/
      DATA ANAME(7) /'        WETDRY PARAMETER'/
C     ------------------------------------------------------------------
C
C1------READ TRPY
      CALL U1DREL(TRPY,ANAME(6),NLAY,IN,IOUT)
C
C2------READ ALL PARAMETERS FOR EACH LAYER.
      KT=0
      KB=0
      DO 200 K=1,NLAY
      KK=K
C
C2A-----FIND ADDRESS OF EACH LAYER IN THREE DIMENSION ARRAYS.
      IF(LAYCON(K).EQ.1 .OR. LAYCON(K).EQ.3) KB=KB+1
      IF(LAYCON(K).EQ.2 .OR. LAYCON(K).EQ.3) KT=KT+1
C
C2B-----READ PRIMARY STORAGE COEFFICIENT INTO ARRAY SC1 IF TRANSIENT.
      IF(ISS.EQ.0)CALL U2DREL(SC1(1,1,K),ANAME(1),NROW,NCOL,KK,IN,IOUT)
C
C2C-----READ TRANSMISSIVITY INTO ARRAY CC IF LAYER TYPE IS 0 OR 2.
      IF(LAYCON(K).EQ.3 .OR. LAYCON(K).EQ.1) GO TO 100
      CALL U2DREL(CC(1,1,K),ANAME(2),NROW,NCOL,KK,IN,IOUT)
      GO TO 110
C
C2D-----READ HYDRAULIC CONDUCTIVITY(HY) IF LAYER TYPE IS 1 OR 3.
  100 CALL U2DREL(HY(1,1,KB),ANAME(3),NROW,NCOL,KK,IN,IOUT)
C
C2E-----READ VERTICAL HYCOND/THICK INTO ARRAY CV IF NOT BOTTOM LAYER;
C2E-----MULTIPLIED BY CELL AREA TO CONVERT TO CONDUCTANCE LATER.
  110 IF(K.EQ.NLAY) GO TO 120
      CALL U2DREL(CV(1,1,K),ANAME(4),NROW,NCOL,KK,IN,IOUT)
C
C2F-----READ SECONDARY STORAGE COEFFICIENT INTO ARRAY SC2 IF TRANSIENT
C2F-----AND LAYER TYPE IS 2 OR 3.
  120 IF(LAYCON(K).NE.3 .AND. LAYCON(K).NE.2) GO TO 130
      IF(ISS.EQ.0)CALL U2DREL(SC2(1,1,KT),ANAME(5),NROW,NCOL,KK,IN,IOUT)
C
C2H-----READ WETDRY CODES IF LAYER TYPE IS 1 OR 3 AND WETTING
C2H-----CAPABILITY HAS BEEN INVOKED (IWDFLG NOT 0).
  130 IF(LAYCON(K).NE.3.AND.LAYCON(K).NE.1)GO TO 200
      IF(IWDFLG.EQ.0)GO TO 200
      CALL U2DREL(WETDRY(1,1,KB),ANAME(7),NROW,NCOL,KK,IN,IOUT)
  200 CONTINUE
C
C3------PREPARE AND CHECK BCF DATA.
      CALL SGWF1BCF6N(HNEW,IBOUND,SC1,SC2,CR,CC,CV,HY,TRPY,DELR,DELC,
     1         ISS,NCOL,NROW,NLAY,IOUT,WETDRY,IWDFLG,CVWD)
C
C4------RETURN
      RETURN
      END
      SUBROUTINE GWF1BCF6AD(IBOUND,HOLD,BOTM,NBOTM,WETDRY,IWDFLG,ISS,
     1                  NCOL,NROW,NLAY)
C
C-----VERSION 11JAN2000 GWF1BCF6AD
C     ******************************************************************
C     SET HOLD TO BOT WHENEVER A WETTABLE CELL IS DRY
C     ******************************************************************
C
C        SPECIFICATIONS:
C     ------------------------------------------------------------------
C
      DIMENSION IBOUND(NCOL,NROW,NLAY),HOLD(NCOL,NROW,NLAY),
     1          BOTM(NCOL,NROW,0:NBOTM),WETDRY(NCOL,NROW,NLAY)
C
      COMMON /DISCOM/LBOTM(200),LAYCBD(200)
      COMMON /BCFCOM/LAYCON(200)
C     ------------------------------------------------------------------
C
C1------RETURN IF STEADY STATE OR IF NOT USING WETTING CAPABILITY
      IF(IWDFLG.EQ.0 .OR. ISS.NE.0) RETURN
C
C2------LOOP THROUGH ALL LAYERS TO SET HOLD=BOT IF A WETTABLE CELL IS DRY
      ZERO=0.
      KB=0
      DO 100 K=1,NLAY
C
C2A-----SKIP LAYERS THAT CANNOT CONVERT BETWEEN WET AND DRY
      IF(LAYCON(K).NE.3 .AND. LAYCON(K).NE.1) GO TO 100
      KB=KB+1
      DO 90 I=1,NROW
      DO 90 J=1,NCOL
C
C2B-----SKIP CELLS THAT ARE CURRENTLY WET OR ARE NOT WETTABLE
      IF(IBOUND(J,I,K).NE.0) GO TO 90
      IF(WETDRY(J,I,KB).EQ.ZERO) GO TO 90
C
C2C-----SET HOLD=BOT
      HOLD(J,I,K)=BOTM(J,I,LBOTM(K))
   90 CONTINUE
  100 CONTINUE
C
C3-----RETURN
      RETURN
      END
      SUBROUTINE GWF1BCF6FM(HCOF,RHS,HOLD,SC1,HNEW,IBOUND,CR,CC,CV,HY,
     1                TRPY,BOTM,NBOTM,SC2,DELR,DELC,DELT,ISS,KITER,
     2                KSTP,KPER,NCOL,NROW,NLAY,IOUT,WETDRY,IWDFLG,CVWD,
     3                WETFCT,IWETIT,IHDWET,HDRY,BUFF)
C-----VERSION 11JAN2000 GWF1BCF6FM
C     ******************************************************************
C     ADD LEAKAGE CORRECTION AND STORAGE TO HCOF AND RHS, AND CALCULATE
C     CONDUCTANCE AS REQUIRED
C     ******************************************************************
C
C        SPECIFICATIONS:
C     ------------------------------------------------------------------
      DOUBLE PRECISION HNEW
C
      DIMENSION HCOF(NCOL,NROW,NLAY),RHS(NCOL,NROW,NLAY),
     1    HOLD(NCOL,NROW,NLAY),SC1(NCOL,NROW,NLAY),HNEW(NCOL,NROW,NLAY),
     2    IBOUND(NCOL,NROW,NLAY),CR(NCOL,NROW,NLAY),
     3    CC(NCOL,NROW,NLAY),CV(NCOL,NROW,NLAY),HY(NCOL,NROW,NLAY),
     4    TRPY(NLAY),BOTM(NCOL,NROW,0:NBOTM),DELR(NCOL),
     5    DELC(NROW),SC2(NCOL,NROW,NLAY),WETDRY(NCOL,NROW,NLAY),
     6    CVWD(NCOL,NROW,NLAY),BUFF(NCOL,NROW,NLAY)
C
      COMMON /DISCOM/LBOTM(200),LAYCBD(200)
      COMMON /BCFCOM/LAYCON(200)
C     ------------------------------------------------------------------
      KB=0
      KT=0
      ONE=1.
      IF(ISS.EQ.0) TLED=ONE/DELT
C
C1------FOR EACH LAYER: IF T VARIES CALCULATE HORIZONTAL CONDUCTANCES
      DO 100 K=1,NLAY
      KK=K
C
C1A-----IF LAYER TYPE IS NOT 1 OR 3 THEN SKIP THIS LAYER.
      IF(LAYCON(K).NE.3 .AND. LAYCON(K).NE.1) GO TO 100
      KB=KB+1
C
C1B-----FOR LAYER TYPES 1 & 3 CALL SGWF1BCF6H TO CALCULATE
C1B-----HORIZONTAL CONDUCTANCES.
      CALL SGWF1BCF6H(HNEW,IBOUND,CR,CC,CV,HY,TRPY,DELR,DELC,BOTM,NBOTM,
     1   KK,KB,KITER,KSTP,KPER,NCOL,NROW,NLAY,IOUT,WETDRY,IWDFLG,
     2   CVWD,WETFCT,IWETIT,IHDWET,HDRY,BUFF)
  100 CONTINUE
C
C2------IF THE SIMULATION IS TRANSIENT ADD STORAGE TO HCOF AND RHS
      IF(ISS.NE.0) GO TO 201
      KT=0
      DO 200 K=1,NLAY
C
C3------SEE IF THIS LAYER IS CONVERTIBLE OR NON-CONVERTIBLE.
      IF(LAYCON(K).EQ.3 .OR. LAYCON(K).EQ.2) GO TO 150
C4------NON-CONVERTIBLE LAYER, SO USE PRIMARY STORAGE
      DO 140 I=1,NROW
      DO 140 J=1,NCOL
      IF(IBOUND(J,I,K).LE.0) GO TO 140
      RHO=SC1(J,I,K)*TLED
      HCOF(J,I,K)=HCOF(J,I,K)-RHO
      RHS(J,I,K)=RHS(J,I,K)-RHO*HOLD(J,I,K)
  140 CONTINUE
      GO TO 200
C
C5------A CONVERTIBLE LAYER, SO CHECK OLD AND NEW HEADS TO DETERMINE
C5------WHEN TO USE PRIMARY AND SECONDARY STORAGE
  150 KT=KT+1
      DO 180 I=1,NROW
      DO 180 J=1,NCOL
C
C5A-----IF THE CELL IS EXTERNAL THEN SKIP IT.
      IF(IBOUND(J,I,K).LE.0) GO TO 180
C      TP=TOP(J,I,KT)
      TP=BOTM(J,I,LBOTM(K)-1)
      RHO2=SC2(J,I,KT)*TLED
      RHO1=SC1(J,I,K)*TLED
C
C5B-----FIND STORAGE FACTOR AT START OF TIME STEP.
      SOLD=RHO2
      IF(HOLD(J,I,K).GT.TP) SOLD=RHO1
C
C5C-----FIND STORAGE FACTOR AT END OF TIME STEP.
      HTMP=HNEW(J,I,K)
      SNEW=RHO2
      IF(HTMP.GT.TP) SNEW=RHO1
C
C5D-----ADD STORAGE TERMS TO RHS AND HCOF.
      HCOF(J,I,K)=HCOF(J,I,K)-SNEW
      RHS(J,I,K)=RHS(J,I,K) - SOLD*(HOLD(J,I,K)-TP) - SNEW*TP
C
  180 CONTINUE
C
  200 CONTINUE
C
C6------FOR EACH LAYER DETERMINE IF CORRECTION TERMS ARE NEEDED FOR
C6------FLOW DOWN INTO PARTIALLY SATURATED LAYERS.
  201 DO 300 K=1,NLAY
C
C7------SEE IF CORRECTION IS NEEDED FOR LEAKAGE FROM ABOVE.
      IF(LAYCON(K).NE.3 .AND. LAYCON(K).NE.2) GO TO 250
      IF(K.EQ.1) GO TO 250
C
C7A-----FOR EACH CELL MAKE THE CORRECTION IF NEEDED.
      DO 220 I=1,NROW
      DO 220 J=1,NCOL
C
C7B-----IF THE CELL IS EXTERNAL(IBOUND<=0) THEN SKIP IT.
      IF(IBOUND(J,I,K).LE.0) GO TO 220
      HTMP=HNEW(J,I,K)
C
C7C-----IF HEAD IS ABOVE TOP THEN CORRECTION NOT NEEDED
C      IF(HTMP.GE.TOP(J,I,KT)) GO TO 220
      IF(HTMP.GE.BOTM(J,I,LBOTM(K)-1)) GO TO 220
C
C7D-----WITH HEAD BELOW TOP ADD CORRECTION TERMS TO RHS.
C      RHS(J,I,K)=RHS(J,I,K) + CV(J,I,K-1)*(TOP(J,I,KT)-HTMP)
      RHS(J,I,K)=RHS(J,I,K) + CV(J,I,K-1)*(BOTM(J,I,LBOTM(K)-1)-HTMP)
  220 CONTINUE
C
C8------SEE IF THIS LAYER MAY NEED CORRECTION FOR LEAKAGE TO BELOW.
  250 IF(K.EQ.NLAY) GO TO 300
      IF(LAYCON(K+1).NE.3 .AND. LAYCON(K+1).NE.2) GO TO 300
C
C8A-----FOR EACH CELL MAKE THE CORRECTION IF NEEDED.
      DO 280 I=1,NROW
      DO 280 J=1,NCOL
C
C8B-----IF CELL IS EXTERNAL (IBOUND<=0) THEN SKIP IT.
      IF(IBOUND(J,I,K).LE.0) GO TO 280
C
C8C-----IF HEAD IN THE LOWER CELL IS LESS THAN TOP ADD CORRECTION
C8C-----TERM TO RHS.
      HTMP=HNEW(J,I,K+1)
C      IF(HTMP.LT.TOP(J,I,KTT)) RHS(J,I,K)=RHS(J,I,K)
C     1                        - CV(J,I,K)*(TOP(J,I,KTT)-HTMP)
      IF(HTMP.LT.BOTM(J,I,LBOTM(K+1)-1)) RHS(J,I,K)=RHS(J,I,K)
     1                        - CV(J,I,K)*(BOTM(J,I,LBOTM(K+1)-1)-HTMP)
  280 CONTINUE
  300 CONTINUE
C
C9------RETURN
      RETURN
      END
      SUBROUTINE SGWF1BCF6C(CR,CC,TRPY,DELR,DELC,K,NCOL,NROW,NLAY)
C
C
C-----VERSION 11JAN2000 SGWF1BCF6C
C     ******************************************************************
C     COMPUTE BRANCH CONDUCTANCE USING HARMONIC MEAN OF BLOCK
C     CONDUCTANCES -- BLOCK TRANSMISSIVITY IS IN CC UPON ENTRY
C     ******************************************************************
C
C      SPECIFICATIONS:
C     ------------------------------------------------------------------
C
      DIMENSION CR(NCOL,NROW,NLAY), CC(NCOL,NROW,NLAY)
     2   , TRPY(NLAY), DELR(NCOL), DELC(NROW)
C
C     ------------------------------------------------------------------
      ZERO=0.
      TWO=2.
      YX=TRPY(K)*TWO
C
C1------FOR EACH CELL CALCULATE BRANCH CONDUCTANCES FROM THAT CELL
C1------TO THE ONE ON THE RIGHT AND THE ONE IN FRONT.
      DO 40 I=1,NROW
      DO 40 J=1,NCOL
      T1=CC(J,I,K)
C
C2------IF T=0 THEN SET CONDUCTANCE EQUAL TO 0. GO ON TO NEXT CELL.
      IF(T1.NE.ZERO) GO TO 10
      CR(J,I,K)=ZERO
      GO TO 40
C
C3------IF THIS IS NOT THE LAST COLUMN(RIGHTMOST) THEN CALCULATE
C3------BRANCH CONDUCTANCE IN THE ROW DIRECTION (CR) TO THE RIGHT.
   10 IF(J.EQ.NCOL) GO TO 30
      T2=CC(J+1,I,K)
      CR(J,I,K)=TWO*T2*T1*DELC(I)/(T1*DELR(J+1)+T2*DELR(J))
C
C4------IF THIS IS NOT THE LAST ROW(FRONTMOST) THEN CALCULATE
C4------BRANCH CONDUCTANCE IN THE COLUMN DIRECTION (CC) TO THE FRONT.
   30 IF(I.EQ.NROW) GO TO 40
      T2=CC(J,I+1,K)
      CC(J,I,K)=YX*T2*T1*DELR(J)/(T1*DELC(I+1)+T2*DELC(I))
   40 CONTINUE
C
C5------RETURN
      RETURN
      END
      SUBROUTINE SGWF1BCF6B(HNEW,IBOUND,CR,CC,CV,NCOL,NROW,NLAY,KSTP,
     1      KPER,IBCFCB,BUFF,IOUT,ICBCFL,DELT,PERTIM,TOTIM,
     2      IDIR,IBDRET,ICHFLG,IC1,IC2,IR1,IR2,IL1,IL2,BOTM,NBOTM)
C
C-----VERSION 11JAN2000 SGWF1BCF6B
C     ******************************************************************
C     COMPUTE FLOW BETWEEN ADJACENT CELLS IN A SUBREGION OF THE GRID
C     ******************************************************************
C
C     SPECIFICATIONS:
C     ------------------------------------------------------------------
      CHARACTER*16 TEXT(3)
      DOUBLE PRECISION HNEW,HD
C
      DIMENSION HNEW(NCOL,NROW,NLAY), IBOUND(NCOL,NROW,NLAY),
     1     CR(NCOL,NROW,NLAY), CC(NCOL,NROW,NLAY),
     2     CV(NCOL,NROW,NLAY), BOTM(NCOL,NROW,0:NBOTM),
     3     BUFF(NCOL,NROW,NLAY)
C
      COMMON /DISCOM/LBOTM(200),LAYCBD(200)
      COMMON /BCFCOM/LAYCON(200)
C
      DATA TEXT(1),TEXT(2),TEXT(3)
     1 /'FLOW RIGHT FACE ','FLOW FRONT FACE ','FLOW LOWER FACE '/
C     ------------------------------------------------------------------
C
C1------IF CELL-BY-CELL FLOWS WILL BE SAVED IN A FILE, SET FLAG IBD.
C1------RETURN IF FLOWS ARE NOT BEING SAVED OR RETURNED.
      ZERO=0.
      IBD=0
      IF(IBCFCB.GT.0) IBD=ICBCFL
      IF(IBD.EQ.0 .AND. IBDRET.EQ.0) RETURN
C
C2------SET THE SUBREGION EQUAL TO THE ENTIRE GRID IF VALUES ARE BEING
C2------SAVED IN A FILE.
      IF(IBD.NE.0) THEN
         K1=1
         K2=NLAY
         I1=1
         I2=NROW
         J1=1
         J2=NCOL
      END IF
C
C3------TEST FOR DIRECTION OF CALCULATION;  IF NOT ACROSS COLUMNS, GO TO
C3------STEP 4.  IF ONLY 1 COLUMN, RETURN.
      IF(IDIR.NE.1) GO TO 405
      IF(NCOL.EQ.1) RETURN
C
C3A-----CALCULATE FLOW ACROSS COLUMNS (THROUGH RIGHT FACE).  IF NOT
C3A-----SAVING IN A FILE, SET THE SUBREGION.  CLEAR THE BUFFER.
      IF(IBD.EQ.0) THEN
         K1=IL1
         K2=IL2
         I1=IR1
         I2=IR2
         J1=IC1-1
         IF(J1.LT.1) J1=1
         J2=IC2
      END IF
      DO 310 K=K1,K2
      DO 310 I=I1,I2
      DO 310 J=J1,J2
      BUFF(J,I,K)=ZERO
  310 CONTINUE
C
C3B-----FOR EACH CELL CALCULATE FLOW THRU RIGHT FACE & STORE IN BUFFER.
      IF(J2.EQ.NCOL) J2=J2-1
      DO 400 K=K1,K2
      DO 400 I=I1,I2
      DO 400 J=J1,J2
      IF(ICHFLG.EQ.0) THEN
         IF((IBOUND(J,I,K).LE.0) .AND. (IBOUND(J+1,I,K).LE.0)) GO TO 400
      ELSE
         IF((IBOUND(J,I,K).EQ.0) .OR. (IBOUND(J+1,I,K).EQ.0)) GO TO 400
      END IF
      HDIFF=HNEW(J,I,K)-HNEW(J+1,I,K)
      BUFF(J,I,K)=HDIFF*CR(J,I,K)
  400 CONTINUE
C
C3C-----RECORD CONTENTS OF BUFFER AND RETURN.
      IF(IBD.EQ.1)
     1   CALL UBUDSV(KSTP,KPER,TEXT(1),IBCFCB,BUFF,NCOL,NROW,NLAY,IOUT)
      IF(IBD.EQ.2) CALL UBDSV1(KSTP,KPER,TEXT(1),IBCFCB,BUFF,NCOL,NROW,
     1     NLAY,IOUT,DELT,PERTIM,TOTIM,IBOUND)
      RETURN
C
C4------TEST FOR DIRECTION OF CALCULATION;  IF NOT ACROSS ROWS, GO TO
C4------STEP 5.  IF ONLY 1 ROW, RETURN.
  405 IF(IDIR.NE.2) GO TO 505
      IF(NROW.EQ.1) RETURN
C
C4A-----CALCULATE FLOW ACROSS ROWS (THROUGH FRONT FACE).  IF NOT SAVING
C4A-----IN A FILE, SET THE SUBREGION.  CLEAR THE BUFFER.
      IF(IBD.EQ.0) THEN
         K1=IL1
         K2=IL2
         I1=IR1-1
         IF(I1.LT.1) I1=1
         I2=IR2
         J1=IC1
         J2=IC2
      END IF
      DO 410 K=K1,K2
      DO 410 I=I1,I2
      DO 410 J=J1,J2
      BUFF(J,I,K)=ZERO
  410 CONTINUE
C
C4B-----FOR EACH CELL CALCULATE FLOW THRU FRONT FACE & STORE IN BUFFER.
      IF(I2.EQ.NROW) I2=I2-1
      DO 500 K=K1,K2
      DO 500 I=I1,I2
      DO 500 J=J1,J2
      IF(ICHFLG.EQ.0) THEN
         IF((IBOUND(J,I,K).LE.0) .AND. (IBOUND(J,I+1,K).LE.0)) GO TO 500
      ELSE
         IF((IBOUND(J,I,K).EQ.0) .OR. (IBOUND(J,I+1,K).EQ.0)) GO TO 500
      END IF
      HDIFF=HNEW(J,I,K)-HNEW(J,I+1,K)
      BUFF(J,I,K)=HDIFF*CC(J,I,K)
  500 CONTINUE
C
C4C-----RECORD CONTENTS OF BUFFER AND RETURN.
      IF(IBD.EQ.1)
     1   CALL UBUDSV(KSTP,KPER,TEXT(2),IBCFCB,BUFF,NCOL,NROW,NLAY,IOUT)
      IF(IBD.EQ.2) CALL UBDSV1(KSTP,KPER,TEXT(2),IBCFCB,BUFF,NCOL,NROW,
     1     NLAY,IOUT,DELT,PERTIM,TOTIM,IBOUND)
      RETURN
C
C5------DIRECTION OF CALCULATION IS ACROSS LAYERS BY ELIMINATION.  IF
C5------ONLY 1 LAYER, RETURN.
  505 IF(NLAY.EQ.1) RETURN
C
C5A-----CALCULATE FLOW ACROSS LAYERS (THROUGH LOWER FACE).  IF NOT
C5A-----SAVING IN A FILE, SET THE SUBREGION.  CLEAR THE BUFFER.
      IF(IBD.EQ.0) THEN
         K1=IL1-1
         IF(K1.LT.1) K1=1
         K2=IL2
         I1=IR1
         I2=IR2
         J1=IC1
         J2=IC2
      END IF
      DO 510 K=K1,K2
      DO 510 I=I1,I2
      DO 510 J=J1,J2
      BUFF(J,I,K)=ZERO
  510 CONTINUE
C
C5B-----FOR EACH CELL CALCULATE FLOW THRU LOWER FACE & STORE IN BUFFER.
      IF(K2.EQ.NLAY) K2=K2-1
      DO 600 K=1,K2
      IF(K.LT.K1) GO TO 600
      DO 590 I=I1,I2
      DO 590 J=J1,J2
      IF(ICHFLG.EQ.0) THEN
         IF((IBOUND(J,I,K).LE.0) .AND. (IBOUND(J,I,K+1).LE.0)) GO TO 590
      ELSE
         IF((IBOUND(J,I,K).EQ.0) .OR. (IBOUND(J,I,K+1).EQ.0)) GO TO 590
      END IF
      HD=HNEW(J,I,K+1)
      IF(LAYCON(K+1).NE.3 .AND. LAYCON(K+1).NE.2) GO TO 580
      TMP=HD
C      IF(TMP.LT.TOP(J,I,KT+1)) HD=TOP(J,I,KT+1)
      IF(TMP.LT.BOTM(J,I,LBOTM(K+1)-1)) HD=BOTM(J,I,LBOTM(K+1)-1)
  580 HDIFF=HNEW(J,I,K)-HD
      BUFF(J,I,K)=HDIFF*CV(J,I,K)
  590 CONTINUE
  600 CONTINUE
C
C5C-----RECORD CONTENTS OF BUFFER AND RETURN.
      IF(IBD.EQ.1)
     1   CALL UBUDSV(KSTP,KPER,TEXT(3),IBCFCB,BUFF,NCOL,NROW,NLAY,IOUT)
      IF(IBD.EQ.2) CALL UBDSV1(KSTP,KPER,TEXT(3),IBCFCB,BUFF,NCOL,NROW,
     1     NLAY,IOUT,DELT,PERTIM,TOTIM,IBOUND)
      RETURN
      END
      SUBROUTINE SGWF1BCF6S(VBNM,VBVL,MSUM,HNEW,IBOUND,HOLD,SC1,
     1   BOTM,NBOTM,SC2,DELT,ISS,NCOL,NROW,NLAY,KSTP,KPER,IBCFCB,
     2   ICBCFL,BUFF,IOUT,PERTIM,TOTIM)
C-----VERSION 11JAN2000 SGWF1BCF6S
C     ******************************************************************
C     COMPUTE STORAGE BUDGET FLOW TERM FOR BCF.
C     ******************************************************************
C
C     SPECIFICATIONS:
C     ------------------------------------------------------------------
      CHARACTER*16 VBNM(MSUM),TEXT
      DOUBLE PRECISION HNEW,STOIN,STOUT,SSTRG
C
      DIMENSION HNEW(NCOL,NROW,NLAY), IBOUND(NCOL,NROW,NLAY),
     1   HOLD(NCOL,NROW,NLAY),SC1(NCOL,NROW,NLAY),VBVL(4,MSUM),
     2   SC2(NCOL,NROW,NLAY),BOTM(NCOL,NROW,0:NBOTM),
     3   BUFF(NCOL,NROW,NLAY)
C
      COMMON /DISCOM/LBOTM(200),LAYCBD(200)
      COMMON /BCFCOM/LAYCON(200)
C
      DATA TEXT /'         STORAGE'/
C     ------------------------------------------------------------------
C
C1------INITIALIZE BUDGET ACCUMULATORS AND 1/DELT.
      ZERO=0.
      STOIN=ZERO
      STOUT=ZERO
C2------IF STEADY STATE, STORAGE TERM IS ZERO
      IF(ISS.NE.0) GOTO 400
      ONE=1.
      TLED=ONE/DELT
C
C3------IF CELL-BY-CELL FLOWS WILL BE SAVED, SET FLAG IBD.
      IBD=0
      IF(IBCFCB.GT.0) IBD=ICBCFL
C
C4------CLEAR BUFFER.
      DO 210 K=1,NLAY
      DO 210 I=1,NROW
      DO 210 J=1,NCOL
      BUFF(J,I,K)=ZERO
210   CONTINUE
C
C5------LOOP THROUGH EVERY CELL IN THE GRID.
      KT=0
      DO 300 K=1,NLAY
      LC=LAYCON(K)
      IF(LC.EQ.3 .OR. LC.EQ.2) KT=KT+1
      DO 300 I=1,NROW
      DO 300 J=1,NCOL
C
C6------SKIP NO-FLOW AND CONSTANT-HEAD CELLS.
      IF(IBOUND(J,I,K).LE.0) GO TO 300
      HSING=HNEW(J,I,K)
C
C7-----CHECK LAYER TYPE TO SEE IF ONE STORAGE CAPACITY OR TWO.
      IF(LC.NE.3 .AND. LC.NE.2) GO TO 285
C
C7A----TWO STORAGE CAPACITIES.
      TP=BOTM(J,I,LBOTM(K)-1)
      RHO2=SC2(J,I,KT)*TLED
      RHO1=SC1(J,I,K)*TLED
      SOLD=RHO2
      IF(HOLD(J,I,K).GT.TP) SOLD=RHO1
      SNEW=RHO2
      IF(HSING.GT.TP) SNEW=RHO1
      STRG=SOLD*(HOLD(J,I,K)-TP) + SNEW*TP - SNEW*HSING
      GO TO 288
C
C7B----ONE STORAGE CAPACITY.
  285 RHO=SC1(J,I,K)*TLED
      STRG=RHO*HOLD(J,I,K) - RHO*HSING

C
C8-----STORE CELL-BY-CELL FLOW IN BUFFER AND ADD TO ACCUMULATORS.
  288 BUFF(J,I,K)=STRG
      SSTRG=STRG
      IF(STRG) 292,300,294
  292 STOUT=STOUT-SSTRG
      GO TO 300
  294 STOIN=STOIN+SSTRG
C
  300 CONTINUE
C
C9-----IF IBD FLAG IS SET RECORD THE CONTENTS OF THE BUFFER.
      IF(IBD.EQ.1) CALL UBUDSV(KSTP,KPER,TEXT,
     1                       IBCFCB,BUFF,NCOL,NROW,NLAY,IOUT)
      IF(IBD.EQ.2) CALL UBDSV1(KSTP,KPER,TEXT,IBCFCB,
     1            BUFF,NCOL,NROW,NLAY,IOUT,DELT,PERTIM,TOTIM,IBOUND)
C
C10-----ADD TOTAL RATES AND VOLUMES TO VBVL & PUT TITLE IN VBNM.
  400 CONTINUE
      SIN=STOIN
      SOUT=STOUT
      VBVL(1,MSUM)=VBVL(1,MSUM)+SIN*DELT
      VBVL(2,MSUM)=VBVL(2,MSUM)+SOUT*DELT
      VBVL(3,MSUM)=SIN
      VBVL(4,MSUM)=SOUT
      VBNM(MSUM)=TEXT
      MSUM=MSUM+1
C
C11----RETURN.
      RETURN
      END
      SUBROUTINE SGWF1BCF6F(VBNM,VBVL,MSUM,HNEW,IBOUND,CR,CC,CV,DELT,
     1         NCOL,NROW,NLAY,KSTP,KPER,IBCFCB,BUFF,IOUT,ICBCFL,
     2         PERTIM,TOTIM,BOTM,NBOTM,ICHFLG)
C-----VERSION 04OCT2000 SGWF1BCF6F
C     ******************************************************************
C     COMPUTE FLOW FROM CONSTANT-HEAD CELLS
C     ******************************************************************
C
C     SPECIFICATIONS:
C     ------------------------------------------------------------------
      CHARACTER*16 VBNM(MSUM),TEXT
      DOUBLE PRECISION HNEW,HD,CHIN,CHOUT,XX1,XX2,XX3,XX4,XX5,XX6
C
      DIMENSION HNEW(NCOL,NROW,NLAY), IBOUND(NCOL,NROW,NLAY),
     1     CR(NCOL,NROW,NLAY), CC(NCOL,NROW,NLAY),
     2     CV(NCOL,NROW,NLAY), VBVL(4,MSUM),
     3     BOTM(NCOL,NROW,0:NBOTM),BUFF(NCOL,NROW,NLAY)
C
      COMMON /DISCOM/LBOTM(200),LAYCBD(200)
      COMMON /BCFCOM/LAYCON(200)
C
      DATA TEXT /'   CONSTANT HEAD'/
C     ------------------------------------------------------------------
C
C1------SET IBD TO INDICATE IF CELL-BY-CELL BUDGET VALUES WILL BE SAVED.
      IBD=0
      IF(IBCFCB.LT.0 .AND. ICBCFL.NE.0) IBD=-1
      IF(IBCFCB.GT.0) IBD=ICBCFL
C
C2------CLEAR BUDGET ACCUMULATORS.
      ZERO=0.
      CHIN=ZERO
      CHOUT=ZERO
      IBDLBL=0
C
C3------CLEAR BUFFER.
      DO 5 K=1,NLAY
      DO 5 I=1,NROW
      DO 5 J=1,NCOL
      BUFF(J,I,K)=ZERO
5     CONTINUE
C
C3A-----IF SAVING CELL-BY-CELL FLOW IN A LIST, COUNT CONSTANT-HEAD
C3A-----CELLS AND WRITE HEADER RECORDS.
      IF(IBD.EQ.2) THEN
         NCH=0
         DO 7 K=1,NLAY
         DO 7 I=1,NROW
         DO 7 J=1,NCOL
         IF(IBOUND(J,I,K).LT.0) NCH=NCH+1
7        CONTINUE
         CALL UBDSV2(KSTP,KPER,TEXT,IBCFCB,NCOL,NROW,NLAY,
     1          NCH,IOUT,DELT,PERTIM,TOTIM,IBOUND)
      END IF
C
C4------LOOP THROUGH EACH CELL AND CALCULATE FLOW INTO MODEL FROM EACH
C4------CONSTANT-HEAD CELL.
      DO 200 K=1,NLAY
      LC=LAYCON(K)
      DO 200 I=1,NROW
      DO 200 J=1,NCOL
C
C5------IF CELL IS NOT CONSTANT HEAD SKIP IT & GO ON TO NEXT CELL.
      IF (IBOUND(J,I,K).GE.0)GO TO 200
C
C6------CLEAR VALUES FOR FLOW RATE THROUGH EACH FACE OF CELL.
      X1=ZERO
      X2=ZERO
      X3=ZERO
      X4=ZERO
      X5=ZERO
      X6=ZERO
      CHCH1=ZERO
      CHCH2=ZERO
      CHCH3=ZERO
      CHCH4=ZERO
      CHCH5=ZERO
      CHCH6=ZERO
C
C7------CALCULATE FLOW THROUGH THE LEFT FACE.
C7------COMMENTS A-C APPEAR ONLY IN THE SECTION HEADED BY COMMENT 7,
C7------BUT THEY APPLY IN A SIMILAR MANNER TO SECTIONS 8-12.
C
C7A-----IF THERE IS NO FLOW TO CALCULATE THROUGH THIS FACE, THEN GO ON
C7A-----TO NEXT FACE.  NO FLOW OCCURS AT THE EDGE OF THE GRID, TO AN
C7A-----ADJACENT NO-FLOW CELL, OR TO AN ADJACENT CONSTANT-HEAD CELL.
      IF(J.EQ.1) GO TO 30
      IF(IBOUND(J-1,I,K).EQ.0) GO TO 30
      IF(IBOUND(J-1,I,K).LT.0 .AND. ICHFLG.EQ.0) GO TO 30
C
C7B-----CALCULATE FLOW THROUGH THIS FACE INTO THE ADJACENT CELL.
      HDIFF=HNEW(J,I,K)-HNEW(J-1,I,K)
      CHCH1=HDIFF*CR(J-1,I,K)
      IF(IBOUND(J-1,I,K).LT.0) GO TO 30
      X1=CHCH1
      XX1=X1
C
C7C-----ACCUMULATE POSITIVE AND NEGATIVE FLOW.
      IF (X1) 10,30,20
   10 CHOUT=CHOUT-XX1
      GO TO 30
   20 CHIN=CHIN+XX1
C
C8------CALCULATE FLOW THROUGH THE RIGHT FACE.
   30 IF(J.EQ.NCOL) GO TO 60
      IF(IBOUND(J+1,I,K).EQ.0) GO TO 60
      IF(IBOUND(J+1,I,K).LT.0 .AND. ICHFLG.EQ.0) GO TO 60
      HDIFF=HNEW(J,I,K)-HNEW(J+1,I,K)
      CHCH2=HDIFF*CR(J,I,K)
      IF(IBOUND(J+1,I,K).LT.0) GO TO 60
      X2=CHCH2
      XX2=X2
      IF(X2)40,60,50
   40 CHOUT=CHOUT-XX2
      GO TO 60
   50 CHIN=CHIN+XX2
C
C9------CALCULATE FLOW THROUGH THE BACK FACE.
   60 IF(I.EQ.1) GO TO 90
      IF(IBOUND(J,I-1,K).EQ.0) GO TO 90
      IF(IBOUND(J,I-1,K).LT.0 .AND. ICHFLG.EQ.0) GO TO 90
      HDIFF=HNEW(J,I,K)-HNEW(J,I-1,K)
      CHCH3=HDIFF*CC(J,I-1,K)
      IF(IBOUND(J,I-1,K).LT.0) GO TO 90
      X3=CHCH3
      XX3=X3
      IF(X3) 70,90,80
   70 CHOUT=CHOUT-XX3
      GO TO 90
   80 CHIN=CHIN+XX3
C
C10-----CALCULATE FLOW THROUGH THE FRONT FACE.
   90 IF(I.EQ.NROW) GO TO 120
      IF(IBOUND(J,I+1,K).EQ.0) GO TO 120
      IF(IBOUND(J,I+1,K).LT.0 .AND. ICHFLG.EQ.0) GO TO 120
      HDIFF=HNEW(J,I,K)-HNEW(J,I+1,K)
      CHCH4=HDIFF*CC(J,I,K)
      IF(IBOUND(J,I+1,K).LT.0) GO TO 120
      X4=CHCH4
      XX4=X4
      IF (X4) 100,120,110
  100 CHOUT=CHOUT-XX4
      GO TO 120
  110 CHIN=CHIN+XX4
C
C11-----CALCULATE FLOW THROUGH THE UPPER FACE.
  120 IF(K.EQ.1) GO TO 150
      IF(IBOUND(J,I,K-1).EQ.0) GO TO 150
      IF(IBOUND(J,I,K-1).LT.0 .AND. ICHFLG.EQ.0) GO TO 150
      HD=HNEW(J,I,K)
      IF(LC.NE.3 .AND. LC.NE.2) GO TO 122
      TMP=HD
      IF(TMP.LT.BOTM(J,I,LBOTM(K)-1)) HD=BOTM(J,I,LBOTM(K)-1)
  122 HDIFF=HD-HNEW(J,I,K-1)
      CHCH5=HDIFF*CV(J,I,K-1)
      IF(IBOUND(J,I,K-1).LT.0) GO TO 150
      X5=CHCH5
      XX5=X5
      IF(X5) 130,150,140
  130 CHOUT=CHOUT-XX5
      GO TO 150
  140 CHIN=CHIN+XX5
C
C12-----CALCULATE FLOW THROUGH THE LOWER FACE.
  150 IF(K.EQ.NLAY) GO TO 180
      IF(IBOUND(J,I,K+1).EQ.0) GO TO 180
      IF(IBOUND(J,I,K+1).LT.0 .AND. ICHFLG.EQ.0) GO TO 180
      HD=HNEW(J,I,K+1)
      IF(LAYCON(K+1).NE.3 .AND. LAYCON(K+1).NE.2) GO TO 152
      TMP=HD
      IF(TMP.LT.BOTM(J,I,LBOTM(K+1)-1)) HD=BOTM(J,I,LBOTM(K+1)-1)
  152 HDIFF=HNEW(J,I,K)-HD
      CHCH6=HDIFF*CV(J,I,K)
      IF(IBOUND(J,I,K+1).LT.0) GO TO 180
      X6=CHCH6
      XX6=X6
      IF(X6) 160,180,170
  160 CHOUT=CHOUT-XX6
      GO TO 180
  170 CHIN=CHIN+XX6
C
C13-----SUM THE FLOWS THROUGH SIX FACES OF CONSTANT HEAD CELL, AND
C13-----STORE SUM IN BUFFER.
 180  RATE=CHCH1+CHCH2+CHCH3+CHCH4+CHCH5+CHCH6
      BUFF(J,I,K)=RATE
C
C14-----PRINT THE FLOW FOR THE CELL IF REQUESTED.
      IF(IBD.LT.0) THEN
         IF(IBDLBL.EQ.0) WRITE(IOUT,899) TEXT,KPER,KSTP
  899    FORMAT(1X,/1X,A,'   PERIOD',I3,'   STEP',I3)
         WRITE(IOUT,900) K,I,J,RATE
  900    FORMAT(1X,'LAYER',I3,'   ROW',I4,'   COL',I4,
     1       '   RATE',1PG15.6)
         IBDLBL=1
      END IF
C
C15-----IF SAVING CELL-BY-CELL FLOW IN LIST, WRITE FLOW FOR CELL.
      IF(IBD.EQ.2) CALL UBDSVA(IBCFCB,NCOL,NROW,J,I,K,RATE,IBOUND,NLAY)
  200 CONTINUE
C
C16-----IF SAVING CELL-BY-CELL FLOW IN 3-D ARRAY, WRITE THE ARRAY.
      IF(IBD.EQ.1) CALL UBUDSV(KSTP,KPER,TEXT,
     1                   IBCFCB,BUFF,NCOL,NROW,NLAY,IOUT)
C
C17-----SAVE TOTAL CONSTANT HEAD FLOWS AND VOLUMES IN VBVL TABLE
C17-----FOR INCLUSION IN BUDGET. PUT LABELS IN VBNM TABLE.
      CIN=CHIN
      COUT=CHOUT
      VBVL(1,MSUM)=VBVL(1,MSUM)+CIN*DELT
      VBVL(2,MSUM)=VBVL(2,MSUM)+COUT*DELT
      VBVL(3,MSUM)=CIN
      VBVL(4,MSUM)=COUT
      VBNM(MSUM)=TEXT
      MSUM=MSUM+1
C
C18-----RETURN.
      RETURN
      END
      SUBROUTINE SGWF1BCF6H(HNEW,IBOUND,CR,CC,CV,HY,TRPY,DELR,DELC
     1,BOTM,NBOTM,K,KB,KITER,KSTP,KPER,NCOL,NROW,NLAY,IOUT
     2,WETDRY,IWDFLG,CVWD,WETFCT,IWETIT,IHDWET,HDRY,BUFF)
C-----VERSION 11JAN2000 SGWF1BCF6H
C     ******************************************************************
C     COMPUTE CONDUCTANCE FOR ONE LAYER FROM SATURATED THICKNESS AND
C     HYDRAULIC CONDUCTIVITY
C     ******************************************************************
C
C      SPECIFICATIONS:
C     ------------------------------------------------------------------
      DOUBLE PRECISION HNEW,HD,BBOT,TTOP
C
      DIMENSION HNEW(NCOL,NROW,NLAY),IBOUND(NCOL,NROW,NLAY)
     1,CR(NCOL,NROW,NLAY), CC(NCOL,NROW,NLAY), CV(NCOL,NROW,NLAY)
     2,HY(NCOL,NROW,NLAY), TRPY(NLAY), DELR(NCOL), DELC(NROW)
     3,BOTM(NCOL,NROW,0:NBOTM),WETDRY(NCOL,NROW,NLAY)
     4,CVWD(NCOL,NROW,NLAY),BUFF(NCOL,NROW,NLAY)
      CHARACTER*3 ACNVRT
      DIMENSION ICNVRT(5),JCNVRT(5),ACNVRT(5)
C
      COMMON /DISCOM/LBOTM(200),LAYCBD(200)
      COMMON /BCFCOM/LAYCON(200)
      COMMON /FLWAVG/LAYAVG(200)
C     ------------------------------------------------------------------
C
C1------LOOP THROUGH EACH CELL IN LAYER AND CALCULATE TRANSMISSIVITY AT
C1------EACH ACTIVE CELL.
      ZERO=0.
      NCNVRT=0
      IHDCNV=0
      ITFLG=1
      IF(IWDFLG.NE.0) ITFLG=MOD(KITER,IWETIT)
      DO 200 I=1,NROW
      DO 200 J=1,NCOL
C
C2------IF CELL IS ACTIVE, THEN SKIP TO CODE THAT CALCULATES SATURATED
C2------THICKNESS.
      IF(IBOUND(J,I,K).NE.0) GO TO 20
C
C3------DETERMINE IF THE CELL CAN CONVERT BETWEEN CONFINED AND
C3------UNCONFINED.  IF NOT, SKIP TO CODE THAT SETS TRANSMISSIVITY TO 0.
      IF(ITFLG.NE.0) GO TO 6
      IF(WETDRY(J,I,KB).EQ.ZERO)GO TO 6
      WD=WETDRY(J,I,KB)
      IF(WD.LT.ZERO) WD=-WD
C      TURNON=BOT(J,I,KB)+WD
      TURNON=BOTM(J,I,LBOTM(K))+WD
C
C3A-----CHECK HEAD IN CELL BELOW TO SEE IF WETTING THRESHOLD HAS BEEN
C3A-----REACHED.
      IF(K.EQ.NLAY)GO TO 2
      HTMP=HNEW(J,I,K+1)
      IF(IBOUND(J,I,K+1).GT.0.AND.HTMP.GE.TURNON)GO TO 9
C
C3B-----CHECK HEAD IN ADJACENT HORIZONTAL CELLS TO SEE IF WETTING
C3B-----THRESHOLD HAS BEEN REACHED.
    2 IF(WETDRY(J,I,KB).LT.ZERO) GO TO 6
      IF(J.EQ.1)GO TO 3
      HTMP=HNEW(J-1,I,K)
      IF(IBOUND(J-1,I,K).GT.0.AND.IBOUND(J-1,I,K).NE.30000.AND.
     1                           HTMP.GE.TURNON)GO TO 9
    3 IF(J.EQ.NCOL)GO TO 4
      HTMP=HNEW(J+1,I,K)
      IF(IBOUND(J+1,I,K).GT.0.AND.HTMP.GE.TURNON)GO TO 9
    4 IF(I.EQ.1)GO TO 5
      HTMP=HNEW(J,I-1,K)
      IF(IBOUND(J,I-1,K).GT.0.AND.IBOUND(J,I-1,K).NE.30000.AND.
     1                            HTMP.GE.TURNON)GO TO 9
    5 IF(I.EQ.NROW)GO TO 6
      HTMP=HNEW(J,I+1,K)
      IF(IBOUND(J,I+1,K).GT.0.AND.HTMP.GE.TURNON)GO TO 9
C
C3C-----CELL IS DRY AND STAYS DRY.  SET TRANSMISSIVITY TO 0, SET
C3C-----SATURATED THICKNESS (BUFF) TO 0, AND SKIP TO THE NEXT CELL.
    6 CC(J,I,K)=ZERO
      IF(LAYAVG(K).EQ.30) BUFF(J,I,K)=ZERO
      GO TO 200
C
C4------CELL BECOMES WET.  SET INITIAL HEAD AND VERTICAL CONDUCTANCE.
C    9 IF(IHDWET.NE.0) HNEW(J,I,K)=BOT(J,I,KB)+WETFCT*WD
C      IF(IHDWET.EQ.0) HNEW(J,I,K)=BOT(J,I,KB)+WETFCT*(HTMP-BOT(J,I,KB))
    9 IF(IHDWET.NE.0) HNEW(J,I,K)=BOTM(J,I,LBOTM(K))+WETFCT*WD
      IF(IHDWET.EQ.0) HNEW(J,I,K)=BOTM(J,I,LBOTM(K))+WETFCT*
     1          (HTMP-BOTM(J,I,LBOTM(K)))
      IF(K.EQ.NLAY) GO TO 12
      IF(IBOUND(J,I,K+1).NE.0) CV(J,I,K)= CVWD(J,I,K)
   12 IF(K.EQ.1) GO TO 14
      IF(IBOUND(J,I,K-1).NE.0) CV(J,I,K-1)= CVWD(J,I,K-1)
   14 IBOUND(J,I,K)=30000
C
C4A-----PRINT MESSAGE SAYING CELL HAS BEEN CONVERTED TO WET.
      NCNVRT=NCNVRT+1
      ICNVRT(NCNVRT)=I
      JCNVRT(NCNVRT)=J
      ACNVRT(NCNVRT)='WET'
      IF(NCNVRT.LT.5) GO TO 20
         IF(IHDCNV.EQ.0) WRITE(IOUT,17) KITER,K,KSTP,KPER
   17    FORMAT(1X,/1X,'CELL CONVERSIONS FOR ITER.=',I3,'  LAYER=',
     1    I3,'  STEP=',I3,'  PERIOD=',I3,'   (ROW,COL)')
         IHDCNV=1
         WRITE(IOUT,18) (ACNVRT(L),ICNVRT(L),JCNVRT(L),L=1,NCNVRT)
   18    FORMAT(1X,3X,5(A,'(',I3,',',I3,')   '))
         NCNVRT=0
C
C5------CALCULATE SATURATED THICKNESS.
   20 HD=HNEW(J,I,K)
C      BBOT=BOT(J,I,KB)
      BBOT=BOTM(J,I,LBOTM(K))
      IF(LAYCON(K).EQ.1) GO TO 50
C      TTOP=TOP(J,I,KT)
      TTOP=BOTM(J,I,LBOTM(K)-1)
      IF(BBOT.GT.TTOP) THEN
         WRITE(IOUT,35) K,I,J
   35    FORMAT(1X,'Negative cell thickness at (Layer,row,col)',
     1   I4,',',I4,',',I4)
         STOP
      END IF
      IF(HD.GT.TTOP) HD=TTOP
   50 THCK=HD-BBOT
C
C6------CHECK TO SEE IF SATURATED THICKNESS IS GREATER THAN ZERO.
      IF(THCK.LE.ZERO) GO TO 100
C
C6A-----IF SATURATED THICKNESS>0 THEN EITHER CALCULATE TRANSMISSIVITY
C6A-----AS HYDRAULIC CONDUCTIVITY TIMES SATURATED THICKNESS OR STORE
C6A-----K IN CC AND SATURATED THICKNESS IN BUFF.
      IF(LAYAVG(K).EQ.30) THEN
         CC(J,I,K)=HY(J,I,KB)
         BUFF(J,I,K)=THCK
      ELSE
         CC(J,I,K)=THCK*HY(J,I,KB)
      END IF
      GO TO 200
C
C6B-----WHEN SATURATED THICKNESS < 0, PRINT A MESSAGE AND SET
C6B-----TRANSMISSIVITY, IBOUND, AND VERTICAL CONDUCTANCE =0
  100 NCNVRT=NCNVRT+1
      ICNVRT(NCNVRT)=I
      JCNVRT(NCNVRT)=J
      ACNVRT(NCNVRT)='DRY'
      IF(NCNVRT.LT.5) GO TO 150
         IF(IHDCNV.EQ.0) WRITE(IOUT,17) KITER,K,KSTP,KPER
         IHDCNV=1
         WRITE(IOUT,18) (ACNVRT(L),ICNVRT(L),JCNVRT(L),L=1,NCNVRT)
         NCNVRT=0
  150 HNEW(J,I,K)=HDRY
      CC(J,I,K)=ZERO
      IF(IBOUND(J,I,K).GE.0) GO TO 160
         WRITE(IOUT,151)
  151    FORMAT(1X,/1X,'CONSTANT-HEAD CELL WENT DRY',
     1          ' -- SIMULATION ABORTED')
         WRITE(IOUT,152) K,I,J,KITER,KSTP,KPER
  152    FORMAT(1X,'LAYER=',I2,'   ROW=',I3,'   COLUMN=',I3,
     1    '   ITERATION=',I3,'   TIME STEP=',I3,'   STRESS PERIOD=',I3)
         STOP
  160 IBOUND(J,I,K)=0
      IF(K.LT.NLAY) CV(J,I,K)=ZERO
      IF(K.GT.1) CV(J,I,K-1)=ZERO
  200 CONTINUE
C
C7------PRINT ANY REMAINING CELL CONVERSIONS NOT YET PRINTED
      IF(NCNVRT.EQ.0) GO TO 203
         IF(IHDCNV.EQ.0) WRITE(IOUT,17) KITER,K,KSTP,KPER
         IHDCNV=1
         WRITE(IOUT,18) (ACNVRT(L),ICNVRT(L),JCNVRT(L),L=1,NCNVRT)
         NCNVRT=0
C
C8------CHANGE IBOUND VALUE FOR CELLS THAT CONVERTED TO WET THIS
C8------ITERATION FROM 30000 to 1.
  203 IF(IWDFLG.EQ.0) GO TO 210
      DO 205 I=1,NROW
      DO 205 J=1,NCOL
      IF(IBOUND(J,I,K).EQ.30000) IBOUND(J,I,K)=1
  205 CONTINUE
C
C9------COMPUTE HORIZONTAL BRANCH CONDUCTANCES FROM TRANSMISSIVITY.
  210 IF(LAYAVG(K).EQ.0) THEN
         CALL SGWF1BCF6C(CR,CC,TRPY,DELR,DELC,K,NCOL,NROW,NLAY)
      ELSE IF(LAYAVG(K).EQ.10) THEN
         CALL SGWF1BCF6A(CR,CC,TRPY,DELR,DELC,K,NCOL,NROW,NLAY)
      ELSE IF(LAYAVG(K).EQ.20) THEN
         CALL SGWF1BCF6L(CR,CC,TRPY,DELR,DELC,K,NCOL,NROW,NLAY)
      ELSE
         CALL SGWF1BCF6U(CR,CC,TRPY,DELR,DELC,BUFF,K,NCOL,NROW,NLAY)
      END IF
C
C10-----RETURN.
      RETURN
      END
      SUBROUTINE SGWF1BCF6N(HNEW,IBOUND,SC1,SC2,CR,CC,CV,HY,TRPY,DELR,
     1    DELC,ISS,NCOL,NROW,NLAY,IOUT,WETDRY,IWDFLG,CVWD)
C
C-----VERSION 11JAN2000 SGWF1BCF6N
C     ******************************************************************
C     INITIALIZE AND CHECK BCF DATA
C     ******************************************************************
C
C        SPECIFICATIONS:
C     ------------------------------------------------------------------
C
      DOUBLE PRECISION HNEW,HCNV
C
      DIMENSION HNEW(NCOL,NROW,NLAY),IBOUND(NCOL,NROW,NLAY)
     1    ,SC1(NCOL,NROW,NLAY),CR(NCOL,NROW,NLAY)
     2    ,CC(NCOL,NROW,NLAY),CV(NCOL,NROW,NLAY)
     3    ,HY(NCOL,NROW,NLAY),TRPY(NLAY),DELR(NCOL),DELC(NROW)
     4    ,SC2(NCOL,NROW,NLAY),WETDRY(NCOL,NROW,NLAY)
     5    ,CVWD(NCOL,NROW,NLAY)
C
      COMMON /BCFCOM/LAYCON(200)
      COMMON /FLWAVG/LAYAVG(200)
C     ------------------------------------------------------------------
C
C1------MULTIPLY VERTICAL LEAKANCE BY AREA TO MAKE CONDUCTANCE.
      ZERO=0.
      IF(NLAY.EQ.1) GO TO 20
      K1=NLAY-1
      DO 10 K=1,K1
      DO 10 I=1,NROW
      DO 10 J=1,NCOL
      CV(J,I,K)=CV(J,I,K)*DELR(J)*DELC(I)
   10 CONTINUE
C
C2------IF WETTING CAPABILITY IS ACTIVATED, SAVE CV IN CVWD FOR USE WHEN
C2------WETTING CELLS.
      IF(IWDFLG.EQ.0) GO TO 20
      DO 15 K=1,K1
      DO 15 I=1,NROW
      DO 15 J=1,NCOL
      CVWD(J,I,K)=CV(J,I,K)
   15 CONTINUE
C
C3------IF IBOUND=0, SET CV=0 AND CC=0.
   20 DO 30 K=1,NLAY
      DO 30 I=1,NROW
      DO 30 J=1,NCOL
      IF(IBOUND(J,I,K).NE.0) GO TO 30
      IF(K.NE.NLAY) CV(J,I,K)=ZERO
      IF(K.NE.1) CV(J,I,K-1)=ZERO
      CC(J,I,K)=ZERO
   30 CONTINUE
C
C4------INSURE THAT EACH ACTIVE CELL HAS AT LEAST ONE NON-ZERO
C4------TRANSMISSIVE PARAMETER.
      HCNV=888.88
      KB=0
      DO 60 K=1,NLAY
      IF(LAYCON(K).EQ.1 .OR. LAYCON(K).EQ.3) GO TO 50
C
C4A-----WHEN LAYER TYPE IS 0 OR 2, TRANSMISSIVITY OR CV MUST BE NONZERO.
      DO 45 I=1,NROW
      DO 45 J=1,NCOL
      IF(IBOUND(J,I,K).EQ.0) GO TO 45
      IF(CC(J,I,K).NE.ZERO) GO TO 45
      IF(K.EQ.NLAY) GO TO 41
      IF(CV(J,I,K).NE.ZERO) GO TO 45
   41 IF(K.EQ.1) GO TO 42
      IF(CV(J,I,K-1).NE.ZERO) GO TO 45
   42 IBOUND(J,I,K)=0
      HNEW(J,I,K)=HCNV
      WRITE(IOUT,43) K,I,J
   43 FORMAT(1X,'NODE (LAYER,ROW,COL)',3I4,
     1      ' ELIMINATED BECAUSE ALL CONDUCTANCES TO NODE ARE 0')
   45 CONTINUE
      GO TO 60
C
C4B-----WHEN LAYER TYPE IS 1 OR 3, HY OR CV MUST BE NONZERO.
   50 KB=KB+1
      DO 59 I=1,NROW
      DO 59 J=1,NCOL
C
C4B1----IF WETTING CAPABILITY IS ACTIVE, CHECK CVWD.
      IF(IWDFLG.EQ.0) GO TO 55
      IF(WETDRY(J,I,KB).EQ.ZERO) GO TO 55
      IF(K.EQ.NLAY) GO TO 51
      IF(CVWD(J,I,K).NE.ZERO) GO TO 59
   51 IF(K.EQ.1) GO TO 57
      IF(CVWD(J,I,K-1).NE.ZERO) GO TO 59
      GO TO 57
C
C4B2----WETTING CAPABILITY IS INACTIVE, SO CHECK CV AT ACTIVE CELLS.
   55 IF(IBOUND(J,I,K).EQ.0) GO TO 59
      IF(K.EQ.NLAY) GO TO 56
      IF(CV(J,I,K).NE.ZERO) GO TO 59
   56 IF(K.EQ.1) GO TO 57
      IF(CV(J,I,K-1).NE.ZERO) GO TO 59
C
C4B3----CHECK HYDRAULIC CONDUCTIVITY.
   57 IF(HY(J,I,KB).NE.ZERO) GO TO 59
C
C4B4----HY AND CV ARE ALL 0, SO CONVERT CELL TO NO FLOW.
      IBOUND(J,I,K)=0
      HNEW(J,I,K)=HCNV
      IF(IWDFLG.NE.0) WETDRY(J,I,KB)=ZERO
      WRITE(IOUT,43) K,I,J
   59 CONTINUE
   60 CONTINUE
C
C5------CALCULATE HOR. CONDUCTANCE(CR AND CC) FOR CONSTANT T LAYERS.
      DO 70 K=1,NLAY
      KK=K
      IF(LAYCON(K).EQ.3 .OR. LAYCON(K).EQ.1) GO TO 70
      IF(LAYAVG(K).EQ.0) THEN
         CALL SGWF1BCF6C(CR,CC,TRPY,DELR,DELC,KK,NCOL,NROW,NLAY)
      ELSE IF(LAYAVG(K).EQ.10) THEN
         CALL SGWF1BCF6A(CR,CC,TRPY,DELR,DELC,KK,NCOL,NROW,NLAY)
      ELSE
         CALL SGWF1BCF6L(CR,CC,TRPY,DELR,DELC,KK,NCOL,NROW,NLAY)
      END IF
   70 CONTINUE
C
C6------IF TRANSIENT, LOOP THROUGH LAYERS AND CALCULATE STORAGE
C6------CAPACITY.
      IF(ISS.NE.0) GO TO 100
      KT=0
      DO 90 K=1,NLAY
C
C6A-----MULTIPLY PRIMARY STORAGE COEFFICIENT BY DELR & DELC TO GET
C6A-----PRIMARY STORAGE CAPACITY.
      DO 80 I=1,NROW
      DO 80 J=1,NCOL
      SC1(J,I,K)=SC1(J,I,K)*DELR(J)*DELC(I)
   80 CONTINUE
C
C6B-----IF LAYER IS CONF/UNCONF MULTIPLY SECONDARY STORAGE COEFFICIENT
C6B-----BY DELR AND DELC TO GET SECONDARY STORAGE CAPACITY(SC2).
      IF(LAYCON(K).NE.3 .AND. LAYCON(K).NE.2) GO TO 90
      KT=KT+1
      DO 85 I=1,NROW
      DO 85 J=1,NCOL
      SC2(J,I,KT)=SC2(J,I,KT)*DELR(J)*DELC(I)
   85 CONTINUE
   90 CONTINUE
C
C7------RETURN.
  100 RETURN
      END
      SUBROUTINE SGWF1BCF6A(CR,CC,TRPY,DELR,DELC,K,NCOL,NROW,NLAY)
C
C-----VERSION 11JAN2000 SGWF1BCF6A
C     ******************************************************************
C-------COMPUTE CONDUCTANCE USING ARITHMETIC MEAN TRANSMISSIVITY
C-------ACTIVATED BY LAYAVG=10
C     ******************************************************************
C
C      SPECIFICATIONS:
C     ------------------------------------------------------------------
C
      DIMENSION CR(NCOL,NROW,NLAY), CC(NCOL,NROW,NLAY)
     2   , TRPY(NLAY), DELR(NCOL), DELC(NROW)
C
C     ------------------------------------------------------------------
      ZERO=0.
      YX=TRPY(K)
C
C1------FOR EACH CELL CALCULATE BRANCH CONDUCTANCES FROM THAT CELL
C1------TO THE ONE ON THE RIGHT AND THE ONE IN FRONT.
      DO 40 I=1,NROW
      DO 40 J=1,NCOL
      T1=CC(J,I,K)
C
C2------IF T=0 THEN SET CONDUCTANCE EQUAL TO 0. GO ON TO NEXT CELL.
      IF(T1.NE.ZERO) GO TO 10
      CR(J,I,K)=ZERO
      GO TO 40
C
C3------IF THIS IS NOT THE LAST COLUMN(RIGHTMOST) THEN CALCULATE
C3------BRANCH CONDUCTANCE IN THE ROW DIRECTION (CR) TO THE RIGHT.
   10 IF(J.EQ.NCOL) GO TO 30
      T2=CC(J+1,I,K)
C3A-----ARITHMETIC MEAN INTERBLOCK TRANSMISSIVITY
      IF(T2.EQ.ZERO) THEN
         CR(J,I,K)=ZERO
      ELSE
         CR(J,I,K)=DELC(I)*(T1+T2)/(DELR(J+1)+DELR(J))
      END IF
C
C4------IF THIS IS NOT THE LAST ROW(FRONTMOST) THEN CALCULATE
C4------BRANCH CONDUCTANCE IN THE COLUMN DIRECTION (CC) TO THE FRONT.
   30 IF(I.EQ.NROW) GO TO 40
      T2=CC(J,I+1,K)
      IF(T2.EQ.ZERO) THEN
         CC(J,I,K)=ZERO
      ELSE
         CC(J,I,K)=YX*DELR(J)*(T1+T2)/(DELC(I+1)+DELC(I))
      END IF
   40 CONTINUE
C
C5------RETURN
      RETURN
      END
      SUBROUTINE SGWF1BCF6L(CR,CC,TRPY,DELR,DELC,K,NCOL,NROW,NLAY)
C
C-----VERSION 11JAN2000 SGWF1BCF6L
C     ******************************************************************
C-------COMPUTE CONDUCTANCE USING LOGARITHMIC MEAN TRANSMISSIVITY
C-------ACTIVATED BY LAYAVG=20
C     ******************************************************************
C
C      SPECIFICATIONS:
C     ------------------------------------------------------------------
C
      DIMENSION CR(NCOL,NROW,NLAY), CC(NCOL,NROW,NLAY)
     2   , TRPY(NLAY), DELR(NCOL), DELC(NROW)
C
C     ------------------------------------------------------------------
      ZERO=0.
      TWO=2.
      HALF=0.5
      FRAC1=1.005
      FRAC2=0.995
      YX=TRPY(K)*TWO
C
C1------FOR EACH CELL CALCULATE BRANCH CONDUCTANCES FROM THAT CELL
C1------TO THE ONE ON THE RIGHT AND THE ONE IN FRONT.
      DO 40 I=1,NROW
      DO 40 J=1,NCOL
      T1=CC(J,I,K)
C
C2------IF T=0 THEN SET CONDUCTANCE EQUAL TO 0. GO ON TO NEXT CELL.
      IF(T1.NE.ZERO) GO TO 10
      CR(J,I,K)=ZERO
      GO TO 40
C
C3------IF THIS IS NOT THE LAST COLUMN(RIGHTMOST) THEN CALCULATE
C3------BRANCH CONDUCTANCE IN THE ROW DIRECTION (CR) TO THE RIGHT.
   10 IF(J.EQ.NCOL) GO TO 30
      T2=CC(J+1,I,K)
      IF(T2.EQ.ZERO) THEN
C3A-----SET TO ZERO AND EXIT IF T2 IS ZERO
         CR(J,I,K)=ZERO
         GO TO 30
      END IF
C3B-----LOGARITHMIC MEAN INTERBLOCK TRANSMISSIVITY
      RATIO=T2/T1
      IF(RATIO.GT.FRAC1.OR.RATIO.LT.FRAC2) THEN
         T=(T2-T1)/LOG(RATIO)
      ELSE
         T=HALF*(T1+T2)
      END IF
      CR(J,I,K)=TWO*DELC(I)*T/(DELR(J+1)+DELR(J))
C
C4------IF THIS IS NOT THE LAST ROW(FRONTMOST) THEN CALCULATE
C4------BRANCH CONDUCTANCE IN THE COLUMN DIRECTION (CC) TO THE FRONT.
   30 IF(I.EQ.NROW) GO TO 40
      T2=CC(J,I+1,K)
      IF(T2.EQ.ZERO) THEN
         CC(J,I,K)=ZERO
         GO TO 40
      END IF
      RATIO=T2/T1
      IF(RATIO.GT.FRAC1.OR.RATIO.LT.FRAC2) THEN
         T=(T2-T1)/LOG(RATIO)
      ELSE
         T=HALF*(T1+T2)
      END IF
      CC(J,I,K)=YX*DELR(J)*T/(DELC(I+1)+DELC(I))
   40 CONTINUE
C
C5------RETURN
      RETURN
      END
      SUBROUTINE SGWF1BCF6U(CR,CC,TRPY,DELR,DELC,BUFF,K,NCOL,NROW,NLAY)
C
C-----VERSION 11JAN2000 SGWF1BCF6U
C     ******************************************************************
C-------COMPUTE CONDUCTANCE USING ARITHMETIC MEAN SATURATED THICKNESS
C-------AND LOGARITHMIC MEAN HYDRAULIC CONDUCTIVITY
C-------NODE HYDRAULIC CONDUCTIVITY IS IN CC,
C-------NODE SATURATED THICKNESS IS IN BUFF
C-------ACTIVATED BY LAYAVG=30
C     ******************************************************************
C
C      SPECIFICATIONS:
C     ------------------------------------------------------------------
C
      DIMENSION CR(NCOL,NROW,NLAY), CC(NCOL,NROW,NLAY)
     2   , TRPY(NLAY), DELR(NCOL), DELC(NROW)
     3   , BUFF(NCOL,NROW,NLAY)
C
C     ------------------------------------------------------------------
      ZERO=0.
      HALF=0.5
      FRAC1=1.005
      FRAC2=0.995
      YX=TRPY(K)
C
C1------FOR EACH CELL CALCULATE BRANCH CONDUCTANCES FROM THAT CELL
C1------TO THE ONE ON THE RIGHT AND THE ONE IN FRONT.
      DO 40 I=1,NROW
      DO 40 J=1,NCOL
      T1=CC(J,I,K)
C
C2------IF T=0 THEN SET CONDUCTANCE EQUAL TO 0. GO ON TO NEXT CELL.
      IF(T1.NE.ZERO) GO TO 10
      CR(J,I,K)=ZERO
      GO TO 40
C
C3------IF THIS IS NOT THE LAST COLUMN(RIGHTMOST) THEN CALCULATE
C3------BRANCH CONDUCTANCE IN THE ROW DIRECTION (CR) TO THE RIGHT.
   10 IF(J.EQ.NCOL) GO TO 30
      T2=CC(J+1,I,K)
      IF(T2.EQ.ZERO) THEN
C3A-----SET TO ZERO AND EXIT IF T2 IS ZERO
         CR(J,I,K)=ZERO
         GO TO 30
      END IF
C3B-----LOGARITHMIC MEAN HYDRAULIC CONDUCTIVITY
      RATIO=T2/T1
      IF(RATIO.GT.FRAC1.OR.RATIO.LT.FRAC2) THEN
         T=(T2-T1)/LOG(RATIO)
      ELSE
         T=HALF*(T1+T2)
      END IF
C3C-----MULTIPLY LOGARITHMIC K BY ARITHMETIC SAT THICK
      CR(J,I,K)=DELC(I)*T*(BUFF(J,I,K)+BUFF(J+1,I,K))
     *               /(DELR(J+1)+DELR(J))
C
C4------IF THIS IS NOT THE LAST ROW(FRONTMOST) THEN CALCULATE
C4------BRANCH CONDUCTANCE IN THE COLUMN DIRECTION (CC) TO THE FRONT.
   30 IF(I.EQ.NROW) GO TO 40
      T2=CC(J,I+1,K)
      IF(T2.EQ.ZERO) THEN
         CC(J,I,K)=ZERO
         GO TO 40
      END IF
      RATIO=T2/T1
      IF(RATIO.GT.FRAC1.OR.RATIO.LT.FRAC2) THEN
         T=(T2-T1)/LOG(RATIO)
      ELSE
         T=HALF*(T1+T2)
      END IF
      CC(J,I,K)=YX*DELR(J)*T*(BUFF(J,I,K)+BUFF(J,I+1,K))
     *            /(DELC(I+1)+DELC(I))
   40 CONTINUE
C
C5------RETURN
      RETURN
      END
