FLOOD05059

• County: Statewide
• Community: Nationwide
• Basin: Statewide
• Title: WSP2 Computer Program
• Date: 5/1/1976
• Prepared By: USDA Soil Conservation Service - Engineering Division
• Floodplain - Doc Type: Educational/Technical/Reference Information

SCS-ENG-18
REV.MAR.1976

REACH

REACH NAME

DRAINAGE AREA
CHANNEL LENGTH
FLOOD LENGTH
DAMAGE LErnGTH
CHANNEL LENGTH

REACH2
XSEC NAME

DISPLACEMENT

VELOCITY

SEGMENT

XSEC NAME
SEGMENT NO

SEGMENT TYPE

LAST STATION

LAST ELEVATION

NVALUE

"n"

"r"

CONTR
COEF OF CONTR

GIRDER

ELEV FULL

ELEV GRDR BOT
SKEW ANGLE
ORIF COEF
WEIR COEF

DATA CARDS
1-5

ENDTABLE

11-20

21-30
31-40
41-50
51-60
61-70

11-20

21-30

31-40

11-20
21-30

31-40

41-50

51-60

DEFINES THE ELEMENTS OF A REACH. TIlE ROAD AND REACH CARDS MUST BE IN TIlE ORDER OF COM-
PUTATIONS SINCE ONLY THE FIRST AND LAST SECTION NAMES ARE SHOW ON THE COMPUTE CARD.

THE NAME OF TIlE RF.ACH, EACH MUST BE UNIQUE. (SEE NOTE 1 SCS-ENG-19) THIS MUST BE THE
SAME NAME AS TIlE CROSS SECTION TO BE USED, UNLESS FOLLOWED BY A REACH2 CARD.

THE DRAINAGE AREA (SQ HILES) AT THE CROSS SECTION (REACH HEAD).

THE HYDRAULIC LENGTH OF THE MAIN CHANNEL SEGMENT (TO NEXT DOWNSTREAM SECTION).

THE HYDRAULIC LENGTH OF THE MAIN FLOODPLAIN (TO NEXT DOWNSTREAM SECTION).

THE LENGTH TO BE USED IN COMPUTING TOTAL ACRES FLOODED IN THE REACH.

THE LENGTH OF CHANNEL IN THE DAMAGE REACH. (SEE TECHNICAL PROCEDURES FOR METHOD OF USE.)

USE THIS CARD ONLY IF THE FOLLOWING DATA IS NEEDED. THIS CARD MUST FOLLOW A REACH CARD.

THE NAME OF THE CROSS SECTION TO BE TRANSPOSED FOR THE PRECEDING REACH. THIS
SECTION MUST BE IN THE CURRENT DATA. IT MAY NOT BE USED IF A LINK CARD HAS BEEN READ
SINCE THE XSEC WAS ENTERED.

THE ELEVATION CHANGE TO BE APPLIED TO EACH SURVEYED POINT ON THE CROSS SECTION.
USE NEGATIVE VALUE IF SECTION IS TO BE LOWERED, POSITIVE IF IT IS TO BE RAISED.

THE VELOCITY AT WHICH SCOUR DAMAGE FIRST OCCURS. THIS IS USED TO COMPUTE ACRES
OF SCOUR. (NOT OPERATIONAL AT PRESErnT)

DESCRIBES ELEMENTS OF A SEGMENT OF A CROSS SECTION. EACH SEGMENT CARD MUST BE FOLLOWED BY
ITS ASSOCIATED 'NVALUE' CARDS. UP TO 6 SEGMENT CARDS MAY BE ENTERED FOR EACH CROSS SECTION.

THE NAME OF THE CROSS SECTION THAT THIS SEGMENT IS A PORTION OF.

ANY NUMBER BETWEEN 1 AND 6, A TOTAL OF 6 SEGMENTS MAY BE USED. THEY MUST BE NUMBERED
CONSECUTIVELY, BUT NOT NECESSARILY ENTERED CONSECUTIVELY. I.E. IF 4 SEGMENTS ARE USED THEY
HAY BE ENTERED 4,2,3,1 BUT NOT BE NUMBERED 4,2,5,1.

THREE SEGMENT TYPE CODES MAY BE USED:

C FOR A CHANNEL SEGMENT. THE WIDTH IS USED TO DETERMINE CHANNEL ACRES FLOODED. CHANNEL
KD VALUES ARE USED AS COMPUTED.
D FOR A DAMAGE SEGMENT. ITS AREA IS INCLUDED IN ACRES FLOODED AND KD VALUES ARE MODIFIED
BY THE SQUARE ROOT OF THE MEANDER FACTOR. (SEE TECHNICAL PROCEDURE).
N FOR A NON DAMAGE SEGMENT. IT IS NOT TO BE INCLUDED IN DAMAGE ACRES FLOODED BUT THE
LENGTH USED IS THE DAMAGE LENGTH. ITS KD VALUES ARE MODIFIED THE SAME AS THE '0' SEGMENT.

THE STATION ON THE CROSS SECTION WHICH MARKS THE END OF THE SEGMENT. THIS MUST BE A
SURVEYED POINT. THIS ALSO INDIRECTLY MARKS THE BEGINNING OF THE SEGMENT NUMBER THAT IS 1
HIGHER THAN THIS NUMBER.

THE ELEVATION ASSOCIATED WITH THE 'LAST STATION' (OPTIONAL). IF THERE IS ONLY ONE
STATION WITH THE 'LAST STATION' VALUE, THE ELEVATION VALUE IS NOT NECESSARY. HOWEVER
IF THE SEGMENT ENDS ON A VERTICAL BANK THIS VALUE WILL INDICATE WHETHER THE SEGMENT
ENDS AT THE TOP OR BOTTOM OF THE BANK.

ENTERS THE 'n' VALUES AND ASSOCIATED HYDRAULIC RADII.
HNOTE THIS CARD MUST ALWAYS FOLLOW THE SEGMENT CARD OR ANOTHER 'n' VALUE CARD.

11-20,31-40,51-60 THE 'n' VALUES TO BE USED. UP TO 4 'n' VALUES MAY BE USED.

21-30,41-50,61-70 THE HYDRAULIC RADIUS ('r') ASSOCIATED WITH THE ABOVE 'n' VALUES.

IF ONLY 1 'n' VALUE IS ENTERED IT IT USED FOR ALL FLOW DEPTHS, IF 2 'n' VALUES AND 1 'r'
IS ENTERED ALL FLOWS WITH 'r' LOWER THAN THE 'r' GIVEN USE THE FIRST 'n' VALUE. ALL FLOWS
WITH AN 'r' GREATER USE TIlE 2ND 'n' VALUE. IF 2 OR MORE 'r'S ARE GIVEN THE 'n' VALUE IS
INTERPRETED ON A STRAIGHT LINE BASIS FOR ALL VALUES OF 'r' WHICH LIE BETWEEN TIlE GIVEN ONES.
IF THE ACTUAL 'r' IS LESS THAN THE FIRST 'r' GIVEN THE FIRST 'n' VALUE IS USED, IF IT IS
GREATER THAN THE LAST 'r' GIVEN THEN THE LAST 'n' VALUE IS USED.

21-30

11-20

21-30
31-40
41-50
51-60

11-70
BY 10
COL.

GIVES THE NEEDED DATA IF THE BRIDGE IS TO BE COMPUTED BY THE CONTRACTED OPENING METHOD.
THE CONTRACTION COEFFICIENT TO USE IN THE CONTRACTION FORMULA.

DESCRIBES THE INDIVIDUAL ITEMS PERTAINING TO AN OPENING (MUST FOLLOW CONTR OR PIER, IF
PIER IS NOT USED IT MUST FOLLOW BPR).

THE ELEVATION WHERE ORIFICE FLOW BEGINS. THIS MUST BE BASED ON THE INDIVIDUALS BEST
JUDGEMENT BUT USUALLY IS SLIGHTLY ABOVE THE POINT WHERE THE GIRDERS ARE ALL SUBMERGED.

THE ELEVATION WHERE THE GIRDERS FIRST BEGIN TO REDUCE FLOW AREA FROM THE CHANNEL.

THE ANGLE OF THE FLOW IN DEGREES WITH THE PERfENPICULAR TO THE CENTER LINE OF THE ROADWAY.

THE COEFFICIENT TO BE USED IN THE ORIFICE FLOW FORMULA WHEN ORIFICE FLOW CONTROLS.

THE WEIR COEFFICIENT FOR FLOW OVER THE BRIDGE DECK. THIS IS COMPUTED SEPARATE FROM THE
FLOW OVER THE ROADWAY PROPER.

THE X AND Y COORDINATES ARE NEEDED TO DESCRIBE THE SHAPE OF THE BRIDGE GIRDER. THESE POINTS
ARE USED TO DEDUCT NET FLOW AREA FROM THE SECTION WHEN FLOW ENCOUNTERS THE GIRDER. TIlE FIRST
AND LAST GIRDER POINTS DEFINE THE WEIR WHEN FLOW OVERTOPS THE GIRDERS. THESE ARE ENTERED Xl,
n, X2, n, ETC. THE FIRST AND LAST POINTS MUST COINCIDE WITH POINTS ON THE ROAD CROSS SECTION
USE ONLY THE NUMBER OF CARDS ACTUAllY NEEDED.

INDICATES THE END OF A GIRDER TABLE.

26