Profiles Check: Multiple Profile Consistency¶

The Profiles Check validates consistency and relationships between multiple steady flow profiles in a HEC-RAS model.

Overview¶

When a model contains multiple profiles (e.g., 10-year, 50-year, 100-year, 500-year floods), certain physical relationships should hold. This check examines:

WSE Ordering (WO) - Water surface elevations should increase with discharge
Discharge Ordering (DO) - Discharges should be ordered consistently
Top Width Ordering (TW) - Top widths should generally increase with discharge
Velocity Consistency (VC) - Velocity relationships across profiles
Flow Regime (FR) - Consistent flow regime across profiles
Boundary Conditions (BC) - Appropriate boundary condition methods

Expected Physical Relationships¶

For typical floodplain hydraulics, as discharge increases:

Parameter	Expected Behavior
Water Surface Elevation (WSE)	Increases
Flow Area	Increases
Top Width	Increases (floodplain activation)
Velocity	Generally increases
Froude Number	May vary with geometry

Exceptions

These relationships may not hold in all cases: - Storage areas and split flow can cause anomalies - Structures may cause flow regime transitions - Complex floodplain geometry can invert relationships

Message Reference¶

WSE Ordering Messages (MP_WO_*)¶

MP_WO_01 - WSE Order Violation¶

Field	Value
Severity	ERROR
Message	WSE for {profile_high} ({wse_high} ft) is lower than {profile_low} ({wse_low} ft) at RS {station}
Cause	Higher discharge profile has lower water surface
Resolution	Review profile discharges and results. May indicate model instability or data error

MP_WO_02 - WSE Crossing¶

Field	Value
Severity	WARNING
Message	WSE profiles cross at RS {station}: {profile1} and {profile2}
Cause	Water surface profiles intersect
Resolution	Profile crossing may indicate storage effects or split flow. Review reach conditions

MP_WO_03 - WSE Order Tolerance¶

Field	Value
Severity	INFO
Message	WSE difference ({diff} ft) between {profile_high} and {profile_low} is within tolerance at RS {station}
Cause	Very small difference between profile WSEs
Resolution	Small differences are acceptable but may indicate model sensitivity

Discharge Ordering Messages (MP_DO_*)¶

MP_DO_01 - Discharge Order Violation¶

Field	Value
Severity	ERROR
Message	Discharge for {profile_high} ({q_high} cfs) is less than {profile_low} ({q_low} cfs) at RS {station}
Cause	Expected higher recurrence interval has lower discharge
Resolution	Review flow data. Discharges should increase with decreasing AEP

MP_DO_02 - Discharge Constant Across Profiles¶

Field	Value
Severity	INFO
Message	Discharge is constant ({q} cfs) across all profiles at RS
Cause	All profiles have same discharge
Resolution	May be intentional for sensitivity analysis. Verify if expected

Top Width Ordering Messages (MP_TW_*)¶

MP_TW_01 - Top Width Order Violation¶

Field	Value
Severity	WARNING
Message	Top width for {profile_high} ({tw_high} ft) is less than {profile_low} ({tw_low} ft) at RS {station}
Cause	Higher discharge has narrower top width
Resolution	May indicate confined channel or complex geometry. Review cross section

MP_TW_02 - Top Width Unchanged¶

Field	Value
Severity	INFO
Message	Top width unchanged across profiles at RS
Cause	Floodplain not activating or confined channel
Resolution	May indicate all flow within channel banks. Verify geometry

Velocity Consistency Messages (MP_VC_*)¶

MP_VC_01 - Velocity Decrease with Higher Discharge¶

Field	Value
Severity	INFO
Message	Velocity for {profile_high} ({v_high} fps) is less than {profile_low} ({v_low} fps) at RS {station}
Cause	Higher discharge has lower velocity
Resolution	Common with floodplain activation (larger area). Review if reasonable

MP_VC_02 - Extreme Velocity¶

Field	Value
Severity	WARNING
Message	Velocity ({v} fps) exceeds {limit} fps for {profile} at RS {station}
Cause	Very high velocity computed
Resolution	Velocities > 20-25 fps are unusual for natural channels. Review geometry

MP_VC_03 - Very Low Velocity¶

Field	Value
Severity	INFO
Message	Velocity ({v} fps) is less than {limit} fps for {profile} at RS {station}
Cause	Very slow flow
Resolution	May indicate ponding or backwater. Review downstream conditions

Flow Regime Messages (MP_FR_*)¶

MP_FR_01 - Flow Regime Inconsistency¶

Field	Value
Severity	WARNING
Message	Flow regime differs between profiles at RS {station}: {profile1}={regime1}, {profile2}={regime2}
Cause	Different profiles have different flow regimes (subcritical vs supercritical)
Resolution	Review flow conditions. Regime transitions may occur at different discharges

MP_FR_02 - Critical Depth for All Profiles¶

Field	Value
Severity	INFO
Message	Critical depth computed for all profiles at RS
Cause	All profiles show critical depth
Resolution	Indicates control section. Verify geometry is appropriate

Boundary Condition Messages (MP_BC_*)¶

MP_BC_01 - Mixed Boundary Methods¶

Field	Value
Severity	WARNING
Message	Different boundary condition methods used across profiles
Cause	Profiles use different downstream boundary types
Resolution	Consistent boundary methods are preferred. Document reasoning for differences

MP_BC_02 - Normal Depth Boundary¶

Field	Value
Severity	INFO
Message	Normal depth boundary condition used for
Cause	Profile uses normal depth at boundary
Resolution	Normal depth is appropriate when channel slope controls. Verify slope value

MP_BC_03 - Known WSE Boundary¶

Field	Value
Severity	INFO
Message	Known water surface boundary ({wse} ft) used for
Cause	Fixed WSE at boundary
Resolution	Known WSE appropriate when controlled by downstream lake, confluence, etc.

Energy Messages (MP_EN_*)¶

MP_EN_01 - Energy Ordering¶

Field	Value
Severity	INFO
Message	Energy grade line for {profile_high} ({egl_high} ft) is lower than {profile_low} ({egl_low} ft) at RS {station}
Cause	Higher discharge has lower energy
Resolution	Unusual but may occur with floodplain effects. Review results

Running Profiles Check¶

Python

from ras_commander.check import RasCheck

# Define profiles in expected order (lowest to highest discharge)
profiles = ['10yr', '50yr', '100yr', '500yr']

# Run profiles check
results = RasCheck.check_profiles(
    plan_hdf,
    profiles=profiles
)

# Review ordering violations
for msg in results.messages:
    if 'order' in msg.message.lower():
        print(f"{msg.station}: {msg.message}")

Customizing Profiles Thresholds¶

Python

from ras_commander.check import create_custom_thresholds, RasCheck

# Create thresholds with custom velocity limits
custom_thresholds = create_custom_thresholds({
    'profiles.wse_order_tolerance_ft': 0.05,  # Stricter WSE tolerance
    'profiles.velocity_max_fps': 20.0,        # Lower velocity limit
    'profiles.velocity_min_fps': 0.2,         # Higher minimum velocity
    'profiles.froude_subcritical_max': 0.95,  # Stricter Froude limit
})

# Run check with custom thresholds
results = RasCheck.check_profiles(plan_hdf, profiles, thresholds=custom_thresholds)

Common Causes of Profile Inconsistencies¶

WSE Order Violations¶

Data entry errors - Wrong discharge assigned to profile
Boundary condition issues - Inappropriate boundary methods
Storage effects - Offline storage activating at higher flows
Split flow - Flow diversion at higher stages
Model instability - Numerical issues at specific profiles

Top Width Anomalies¶

Confined valley - Steep valley walls limit expansion
Ineffective flow - Trigger elevations causing jumps
Levees - Levee overtopping changes width relationships
Structures - Bridge openings constraining flow

Velocity Anomalies¶

Floodplain activation - Larger area at higher flows
Backwater effects - Downstream controls
Geometry transitions - Width changes affecting velocity

References¶

HEC-RAS User's Manual
FEMA Guidelines and Specifications for Flood Hazard Mapping Partners
Hydraulic Engineering Circular No. 25 (HEC-25)