Levees and Property Flood Screening

Mapped intersection and nearby infrastructure are different

TrueViewly checks whether the location intersects a retained official USACE National Levee Database leveed-area polygon. A separate bounded search lists nearby mapped embankments and floodwalls within five miles by default.

• A nearby line does not establish that the system protects this location.
• Multiple mapped systems may intersect, and displayed lists are capped.
• No mapped intersection is not a low-flood-risk finding; unmapped or incomplete records remain possible.

Inspection and accreditation are dated records

System metadata can show accreditation, inventory status, inspection ratings and assessment dates. These source records can have different vintages and are not failure probabilities or a current engineering certification.

• An older inspection rating must be read with its date; it is not a newly performed inspection.
• Accreditation is not a guarantee of protection or an insurance determination.
• The displayed preparation/import date does not make the original inspection current.

Keep FEMA context and residual flood risk in the review

Levee evidence does not change the existing hydrology or overall score. It adds verification questions alongside mapped flood zones, drainage, rainfall, surface water and regional insured-loss history.

• Ask the floodplain administrator for the applicable effective FIRM and mapped levee context.
• Ask the system sponsor or emergency management about operations, evacuation and residual-risk information.
• Confirm actual coverage, exclusions and requirements with an insurance professional.

Read coverage and source quality explicitly

The report distinguishes a retained no-match from an unavailable lookup. Prepared data exclude quarantined line records and retain audited polygon repairs; an inventory is not a complete parcel survey.

• Mapped-area and nearby-infrastructure lookups have independent availability states.
• A US-focused dataset does not guarantee a usable record at every territory or address.
• The Sonoma sample demonstrates no intersection; it does not demonstrate absence of flood hazard.

Sources and further reading

• USACE National Levee Database

Source publications and live agency pages may differ from the snapshot used in a report. Check the report's source dates and confirm material findings through the responsible authority.