Chapter 17.17 — 200-YEAR FLOOD PROTECTION

This chapter implements the requirements of Senate Bill 5 (2007) and related legislation that prohibit approval of urban development in urban and urbanizing areas that are exposed to 200-year flooding risk unless certain findings are made. These requirements are established in the California Government Code at Sections 65865.5, 65962 and 66474.5, as amended. (Ord. 16-361 § 1)

"200-year floodplain map" is a map approved by the city engineer for urban and urbanizing areas that depicts geographic areas that may be exposed to 200-year frequency flooding, and, if available, the depth of flooding during a 200-year flooding event.

"200-year frequency flooding" is the level of flooding that has a one in 200 chance of occurring in any given year using criteria consistent with, or developed by, the California Department of Water Resources.

"Adequate progress" is as defined in California Government Code Section 65007 .

"Flood hazard zone" is an area subject to flooding that is delineated as either a special hazard area or an area of moderate or minimal hazard on an official flood insurance rate map issued by the Federal Emergency Management Agency (FEMA), as also defined in Section 15.56.050 .

"New development" is defined as:

1. A development agreement; or

2. A tentative subdivision map, or a parcel map for which a tentative map was not required; or

3. A discretionary permit or other discretionary entitlement that would result in the construction of a new building or construction that would result in an increase in allowed occupancy for an existing building; or

4. A ministerial permit that would result in the construction of a new residence.

"Urban areas and urbanizing areas" are lands within the city of Lathrop that are also within Reclamation District 17 or Reclamation District 2062.

"Urban level of flood protection (ULOP)" means the level of protection that is necessary to withstand 200-year frequency flooding. ULOP shall not mean shallow flooding or flooding from local drainage that meets the criteria of the national Federal Emergency Management Agency standard of flood protection (Government Code Section 65007 ). (Ord. 16-361 § 1)

After July 2, 2016, unless that date is amended by the State Legislature, new development shall not be approved where 200-year flooding, as shown on a 200-year floodplain map, will exceed three feet in depth, or in flood hazard zones where 200-year floodplain maps have not been approved by the city engineer, unless the approval authority determines based on substantial evidence in the record that:

• A. The facilities of the State Plan of Flood Control or other flood management facilities protect the new development site to the urban level of flood protection in urban and urbanizing areas or the national Federal Emergency Management Agency standard of flood protection in non-urbanized areas; or

• B. Conditions imposed on the new development will protect the property to the urban level of flood protection in urban and urbanizing areas or the national Federal Emergency Management Agency standard of flood protection in non-urbanized areas; or

• C. The local flood management agency has made adequate progress on the construction of a flood protection system that will result in flood protection equal to or greater than the urban level of flood protection in urban or urbanizing areas, or the national Federal Emergency Management Agency standard of flood protection in non-urbanized areas, for a new development site located within a flood hazard zone intended to be protected by the system. For urban and urbanizing areas protected by project levees, the urban level of flood protection shall be achieved by 2025; or

• D. The new development site located in an undetermined risk area has met the urban level of flood protection based on substantial evidence in the record.

• (Ord. 16-361 § 1)