FLOOD08201

• County: Statewide
• Community: State of Colorado
• Basin: Statewide
• Title: The NWS Dambrk Model Quick Users Guide
• Date: 6/20/1988
• Prepared By: National Weather Service
• Floodplain - Doc Type: Educational/Technical/Reference Information

Appendix A-4

(9)

YO

Z
YBMIN

BB
TFH

DATUM
VOL

:~,~:~~~,~:: ":-:<':\'

Elevation (ft) of water surface in reservoir when
computation commences; elevation is referenced to
m.S,l, datum. When card (8) represents a bridge
(see note on page A-23), YO = 0.0.
Side slope (l:vertical to z:horizontal) of breach.
Lowest elevation (ft) that bottom of breach reaches;
elevation is referenced to m.s.l. datum.
Width (ft) of base of breach.
Time (hr) from beginning of breach formation until it
reached its maximum size.
Elevation (m.s.l.) of bottom of dam.
Parameter indicating if SA(K) is surface area (acres)
or volume (acre-ft); if VOL=O.O, SA(K) is acres; if
VOL=1.0, SA(K) is acre-ft and SA(K), K - 1,8 will
be automatically converted to acres; if VOL> 1.0
where VOL - SA(l), in acres, SA(K) is acre-ft and
SA(K), K = 2,8 will be a'ltomatically converted to
acres. The last option (VOL> 1.0) helps provide a
reasonable conversion from volume to surface area
and should be used if at all possible. Of course,
if a surface area table is known, it should be used
rather than a volume table.

HF

HF, HD, HSP, HGT, CS, CG, COO, QT - 8 F 10.0 Format

HD

HSP

HGT

CS

CG

CDO

Elevation (ft) of water when failure of dam
commences; elevation is referenced to m.s.l. datum;
if HF is entered with a negative value, failure
will commence at a certain time given by IHFI where
HF has units of hours.
Elevation (ft) of top of darn; elevation is referenced
to m.s.l. datum; if HD is entered as a negative
value, the length of the darn crest is variable with
elevation as described for cards (10 & 11).
Elevation (ft) of uncontrolled spillway crest;
elevation is referenced to m.s.l, datum; if HSP is
entered as a negative value, the failure starts in
the spillway at its crest and failure is confined
to a length along the dam of CS/3.0 which
approximates the length of the spillway,
Elevation (ft) of center of gate openings; elevation
is referenced to m.s.l. datum. Also, elevation
(m,s.l.) of bottom of sill of time-dependent gate.
Discharge coefficient for uncontrolled spillway; it
is equal to the coefficient of discharge (2,6-3,2)
times the length (ft) of the spillway.
Discharge coefficient for gate flow; it is equal to
the coefficien~ o~ discharge (0.60-0,80) times the
area of gates (ft ).
Discharge coefficient for uncontrolled weir flow over
the top of the darn; it is equal to the coefficient
of discharge (2.6-3.2) times the length of the dam

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