Based on the available Elevation Certificate documenting LAG at 52.4 ft NAVD88 (0.4 ft above BFE of 52.0 ft), this property appears to meet the primary criterion for LOMA eligibility. A successful LOMA application would remove the mandatory flood insurance purchase requirement — eliminating an estimated $1,240+ annual insurance obligation. This report provides the full analytical basis and referral guidance for pursuing the LOMA application.
The 2024 Flood Insurance Study for the Willow Creek basin was conducted using LiDAR-derived digital elevation data at sub-meter accuracy and updated hydrologic analysis incorporating recent stream gauge records. The BFE of 52 feet NAVD88 at this property location reflects a step-backwater hydraulic model calibrated to the 1% annual chance flood event for Willow Creek at the cross-section nearest this property. The LiDAR basis of this study is more accurate than prior contour-map based studies, which means the BFE is more reliable — and, paradoxically, more precisely challengeable via LOMA if EC data documents above-BFE conditions at the property.
Because the 2024 BFE is LiDAR-derived, the terrain model used to establish the BFE and the terrain model used to document the property's LAG on the EC are based on compatible high-resolution data. This reduces the risk of datum or methodology conflicts in a LOMA application — a common complication when older BFE data meets newer survey data. The 2023 EC and 2024 BFE are methodologically compatible, strengthening the LOMA application basis.
Based on available EC data, this property appears to meet the primary LOMA eligibility criterion. The Lowest Adjacent Grade of 52.4 feet NAVD88 exceeds the BFE of 52.0 feet by 0.4 feet. We recommend engaging a licensed engineer or land surveyor to prepare a formal LOMA application using the existing EC as the basis. This report provides the analytical foundation; the engineer provides the certification required by FEMA.
| LOMA Type Applicable | MT-EZ (single lot/structure, owner-initiated) |
| Controlling Criterion | Lowest Adjacent Grade ≥ BFE |
| Documented LAG | 52.4 ft NAVD88 ✓ meets criterion |
| BFE at Property | 52.0 ft NAVD88 |
| LAG Margin Above BFE | +0.4 ft (thin but positive) |
| EC Vintage | 2023 — within acceptable age for FEMA MT-EZ submission |
| EC Preparer | Licensed surveyor (per EC documentation) |
| LOMA Application Process | MT-EZ form + certified EC + application fee (~$500–$800 for engineer prep) |
| FEMA Processing Time | Typically 60–90 days |
| LOMA Outcome if Granted | Property removed from SFHA — mandatory purchase requirement eliminated |
A 0.4-foot margin above BFE is positive but not wide. FEMA's MT-EZ process requires a licensed engineer or land surveyor to certify that the LAG is at or above BFE. The 2023 EC was prepared by a licensed surveyor with NAVD88 datum, consistent with the 2024 BFE. However, if any re-survey were to document the LAG at or below BFE (within survey tolerance), the application would be denied. The narrow margin suggests engaging the original EC preparer for the LOMA application — their survey instruments and datum references will be most consistent with the original EC data, minimizing re-survey risk.
FEMA reviews the MT-EZ application, certified EC, and supporting data. If the application is complete and EC data supports the LAG criterion, FEMA issues a LOMA — a formal letter amending the FIRM to show the specific lot or structure as removed from the SFHA. The LOMA is recorded and searchable in FEMA's amendment database. Once issued, the owner provides the LOMA to their lender, who is required to accept it and remove the mandatory insurance requirement. Voluntary flood insurance after a LOMA is advisable — the LOMA removes the mandatory requirement but not the physical flood risk.
At an estimated LOMA application cost of approximately $1,300 (engineer certification + FEMA filing fee) and annual mandatory insurance savings of $1,240, the payback period is approximately 13 months. Over a 10-year horizon, the net benefit of a successful LOMA is approximately $11,100 (savings minus application cost). The Oregon real estate disclosure obligation for SFHA properties is also eliminated by a LOMA, which may have additional value in any future sale. This is among the most compelling LOMA economic cases in this report set.
A LOMA removes the mandatory purchase requirement — it does not eliminate flood risk. Willow Creek flooding remains a physical possibility regardless of the LOMA. If insurance is discontinued following a LOMA, the property owner assumes full flood risk exposure. For a structure valued at approximately $520,000 (estimated), voluntary flood insurance at competitive private market rates post-LOMA would be approximately $400–$600/year — substantially less than the current mandatory cost. The decision to carry voluntary insurance after LOMA is the owner's, but the risk context should be understood.
The City of Portland maintains a Class 6 CRS rating — one of the stronger ratings in the Pacific Northwest — reflecting the City's floodplain management ordinance, public outreach, flood damage reduction activities, and open space preservation along flood corridors. Portland's Bureau of Development Services administers floodplain development permits. Portland's ordinance meets or exceeds federal minimum NFIP standards and includes freeboard requirements (typically 1 foot above BFE for new construction) beyond federal minimums.
Portland enforces the 50% substantial improvement rule consistent with federal minimums. At an estimated structure value of $520,000, the threshold is approximately $260,000. Portland also enforces a cumulative substantial improvement tracking methodology. Given the elevated construction (pier/post) and LFE well above BFE, compliance with current standards if the threshold is triggered would be simpler than for slab-on-grade properties — the structure is already above BFE and would not require elevation work. Any triggered compliance would primarily involve administrative documentation rather than structural modification.
Step 1: Contact the licensed land surveyor who prepared the 2023 EC. Provide them a copy of this report and the FEMA MT-EZ application form (available at msc.fema.gov). Ask them to certify the LAG data from the existing EC for LOMA submission purposes and confirm whether a re-survey is needed given the 0.4-foot margin.
Step 2: Submit the MT-EZ application to FEMA with the certified EC. Application processing typically takes 60–90 days. FEMA may request additional information during review.
Step 3: If LOMA is issued, provide to lender and contact insurance carrier. If NFIP policy is in force, the policy can be converted to lower-cost coverage or cancelled with potential refund if within the policy term.
If LOMA is denied: A licensed engineer may identify additional data (fill documentation, additional survey points) that could support a revised application. FEMA's Scientific/Technical Appeals process is also available within 90 days of FIRM effective date — that window has passed for the March 2024 panel, but the standard LOMA process remains open.