Basalt P&Z endorses floodplain code updates tied to new FEMA/CWCB maps; River Oaks area sees increased mapping

The Town of Basalt Planning & Zoning Commission on Nov. 18 recommended that the town council adopt updates to flood-damage prevention provisions in chapter 16 to reference newly revised floodplain maps developed through the Colorado Water Conservation Board (CWCB) and FEMA process.

Town engineer Katherine Kristoff presented the updates and said the mapping work began in 2018 and used updated survey and LiDAR data. She told the commission that FEMA and CWCB consider the maps final following public notice and a 90-day appeal period. "We're reaching the end of this long process," she said, and noted the maps will be effective on Jan. 9; state requirements obligate the town to update code references accordingly.

Commission questions focused on which areas are most affected and the practical consequences for homeowners. Staff explained that some floodway delineations were narrowed based on state rules that allow up to a 6-inch rise, while the town will still require a no-rise condition for developments. The River Oaks subdivision was identified as an area where more properties will now be included in the regulatory floodplain because of ground-truthing and updated survey data.

On insurance and permitting, staff said federal processes such as letters of map revision are separate but relevant: properties newly mapped in the floodplain with federally backed mortgages will be required to purchase flood insurance. On improvements, staff said additions generally must keep the first finished floor at least two feet above base flood elevation and must demonstrate they will not increase the base flood elevation for neighboring properties.

Public comment was opened and none was received. A commissioner moved and another seconded to recommend the code updates; the motion passed by voice vote and staff will forward the recommendation to council with supporting mapping documentation. The commission noted outreach to affected homeowners in River Oaks and that at least one homeowner supplied additional survey data during the process.