This is a high-risk coastal lot. You're in FEMA Zone VE — the coastal high-hazard zone — with a base flood elevation of 14 ft NAVD88. That means flood insurance is mandatory, the lender will require it, and any structure must be elevated on piles or columns above the BFE with breakaway walls below. NWI shows estuarine wetlands within 250 ft. The good news: this is well-trodden territory in Galveston, and the local code reflects it. Just don't underestimate the build cost — elevated coastal construction runs 30–50% more than a slab-on-grade home of the same size, and insurance is a permanent line item.
| Layer | Finding | What it means |
|---|---|---|
| FEMA flood zone | Zone VE · BFE +14 ft NAVD88 | Coastal high-hazard. Wave action expected. Mandatory flood insurance + elevated construction. |
| Wetlands (NWI) | Estuarine wetland 250 ft NW | E2EM1P (intertidal emergent). Setback rules vary; verify USACE jurisdiction before grading. |
| Soil (SSURGO) | Galveston fine sand (saline) | Hydrologic group A. Drainage: excessively drained. Salt-corrosive — protect rebar/fasteners. |
| Slope | 0.5% | Effectively flat. Drainage will rely on local grading and tide level. |
| Elevation | 8 ft NAVD88 | 6 ft below BFE — finished floor must be 14 ft+, so structure elevated 6+ ft above existing grade. |
| Streams (NHD) | Gulf shoreline 320 ft S | Coastal Construction Control Line likely applies. Confirm with TX GLO. |
| Land cover | Developed, low intensity | ~25% impervious typical for area. Shell/sand substrate dominant. |
| Design rainfall | 100-yr / 24-hr: 13.2 in | Galveston gets tropical-system rainfall. Driveway and yard ponding routine. |
Implications: Zone VE is the most restrictive FEMA designation. Construction must be on open piles, columns, or shear walls (no enclosed living space below BFE). Breakaway walls allowed only for parking, storage, or building access. Flood insurance under NFIP is mandatory if you have a federally backed mortgage. Premiums for VE construction in Galveston commonly run $4,000–$10,000/yr depending on coverage and structure value.
Implications: Pile foundations are the standard solution for VE construction here and the soils accept them well. Specify hot-dip galvanized hardware or stainless fasteners — coastal salt + sand is corrosive. Below-grade utilities (sewer, water laterals) need chloride-resistant materials.
| Duration | 2-yr | 10-yr | 25-yr | 100-yr |
|---|---|---|---|---|
| 15-min | 0.96" | 1.43" | 1.71" | 2.13" |
| 1-hr | 2.34" | 3.71" | 4.62" | 6.07" |
| 24-hr | 5.66" | 8.94" | 10.7" | 13.2" |
Implications: Galveston design rainfall is among the highest in Texas. Tropical Storm Allison-type events have produced 24-hr totals of 30+ inches — far above the regulatory 100-yr value. Site grading and yard drainage will not eliminate ponding during major events; design with that expectation.