Elevation Certificates in Lodi, CA

Lodi was first called Mokelumne Station after the river that forms its northern edge, and the city's own stormwater page says rain and irrigation runoff here drains to the Mokelumne River, Lodi Lake, or one of the Woodbridge Irrigation District canals. The city sits on flat ground at roughly 50 feet above sea level, so the flood questions we expect here are tied to specific waterways and low spots rather than to a single levee basin.

A flood hazard analysis the city published for its White Slough pond project, west of town, gives a sense of how the FIRM is read here. It identifies the Mokelumne River to the north and the Calaveras River to the south as the large rivers capable of major flooding in a 100-year event, with Bear Creek as the nearest smaller waterway, and reads the base flood elevation off the countywide FIRM on the NAVD 88 datum. That is the same datum check we make on every Lodi certificate: the benchmark tie and the BFE have to be on the same vertical datum or the comparison is meaningless. The city's storm preparedness page points owners to the FEMA Flood Map Service Center at msc.fema.gov as the official source, and San Joaquin County runs a 200-year floodplain viewer that shows locally mapped hazards beyond the FEMA zones.

On site we tie to a published benchmark with GNSS, then use a Trimble S3 total station to shoot the lowest adjacent grade, the highest adjacent grade, the top of the bottom floor, garage slab, crawlspace and vent openings, and any machinery or utilities serving the building. We photograph each elevation of the structure and deliver a signed FEMA elevation certificate. If the ground at the structure is at or above the BFE, the data can support a letter of map amendment, and we can submit eligible requests through eLOMA. Lodi work is scheduled as a mobilization from our base in Lotus. More on the elevation certificate service, the Stockton and Galt pages, and our Lodi area page.