Constructing improvements in the floodplain has the potential to impact flood levels. If not properly designed, a structure may be susceptible to flood damage or may cause flood damage to adjacent properties. Improvements or repairs to existing structures in the floodplain, such as remodels or garage conversions, would require review by city officials to determine if such improvements would constitute a "substantial improvement" as defined by Federal Regulations (Substantial Improvement is activated if the cost of the new improvements or repairs exceeds 50% of the value of the original structure).

If improvements are not constructed to Federal standards, this may affect the ability of the owner to obtain flood insurance or a loan on the structure. Flood relief assistance funds may also be withheld if the structure is not in compliance with Federal requirements

All development or improvements within the City's floodplain requires a Development Permit from the City of Roseville. Depending on the type of development, there are four documents that are used to manage development in the floodplain:

Newly developing areas are subject to the General Plan's Safety Element and the Design Standards. Existing developed areas are subject to the Flood Damage Prevention Ordinance and the Zoning Ordinance. If you are planning improvements in the floodplain or would like to report activities in the floodplain that appear to be un-permitted, please contact the Public Works - Engineering at (916) 746-1300 or engineering@roseville.ca.us.