City of Lathrop SB-5 200 Year Flood Protection General Plan Amendment

In 2007, the State of California approved the SB 5 bills that require 200-year Urban Level of Flood Protection for urban areas in the Central Valley. All of the relevant bills are shown in the appendix of the GPA. Briefly summarized, the SB 5 Bills require that urban (population > 10,000) and urbanizing areas (population > 10,000 within ten years) have 200-year flood protection no later than 2025. After July 2, 2016, the City is prohibited from issuing new discretionary permits in areas that may be inundated to a depth of more than three feet during a 200-year flooding event unless the City confirms that 1) 200-year flood protection is provided, or 2) “adequate progress” has been made toward providing 200-year flood protection by 2025.

The SB 5 Bills require that the 200-year flood protection requirements be incorporated into amendments of the City’s general plan and zoning. General plan amendments must be completed by July 2015; zoning amendments must be completed by July 2016. The proposed GPA being presented to the City Council for approval will meet the 2015 general plan amendment requirement; following adoption of the GPA, staff will begin preparing the 2016 zoning amendment.

The City of Lathrop is protected from potential flooding by FEMA-certified 100-year levees; the levees are maintained by three local reclamation districts (RDs): RD 17, RD 2062 and RD 2107. RD 17 and the City are jointly planning 200-year levee improvements along the east bank of the San Joaquin River to provide 200-year flood protection by 2025, and to demonstrate “adequate progress” by July 2, 2016. RD 2062 has improved levees for the River Islands Stage 1 area and is preparing information that will support 200-year ULOP certification of these levees by July 2, 2016. Improvements to RD 2062 levees protecting the remainder of the River Islands project will occur at a later date; these future urban areas will also be subject to the requirements of the SB 5 Bills. The proposed GPA will apply to these River Islands areas as well as the rest of the City. The process of planning, engineering, documenting and certifying 200-year levees is highly technical and complex. Nonetheless, all of the involved parties are moving forward with the intent of meeting the applicable 200-year requirements.

RD 2107, which includes Dell’Osso Farms and other areas south of the Union Pacific Railroad and southeast of I-5, does not presently have 100-year flood protection and is neither urban nor urbanizing. The SB 5 Bills therefore do not impose the requirement for 200-year flood protection within RD 2107.

The City has adopted a general plan in accordance with the requirements of the California Government Code. The general plan is considered the City’s “constitution for future development” and includes seven required elements: Land Use, Circulation, Housing, Conservation, Open-Space, Safety and Noise. Flood protection concerns are addressed primarily in the Safety Element. The general plan must be both comprehensive in its treatment of land use and related issues, and must also be “internally consistent.”

The Lathrop General Plan (the “LGP”), adopted in 1991, and amended several times, addresses the range of subjects required by the Government Code, including Safety, and in particular, flooding. Flooding hazards are defined with respect to the FEMA 100-year floodplain standard, which is the continuing basis for the National Flood Insurance Program (NFIP); the City is active in managing flooding risks in accordance with the NFIP. The LGP does not address 200-year flooding; the proposed GPA will modify the LGP to conform to SB 5 Bill requirements while maintaining internal consistency.

The GPA incorporates the applicable requirements of the SB 5 Bills into the Lathrop General Plan. The GPA would be accomplished by adopting the document entitled City of Lathrop, Comprehensive General Plan – Draft General Plan Amendment of 2015, SB 5 200-Year Flood Protection, which is Staff Report Attachment 2. The GPA includes descriptions of:

Existing 200-year flooding risk, including available 200-year floodplain mapping
Existing flood protection facilities and programs operated by the agencies with jurisdiction, including the City, reclamation districts, and the State and federal governments
Land and improvements exposed to 200-year flooding, and their value
Provisions for prevention and response to flooding emergencies

The principal element of the GPA is a set of goals, policies, objectives and implementation measures (GPA Section 2.9) that respond directly to the requirements of the SB 5 Bills. Primarily, the GPA establishes 200-year flood protection as a City development standard and prohibits Lathrop approval of development within RD 17 or RD 2062 after July 2, 2016 unless the requirements of the SB 5 Bills are met: 1) 200-year flood protection is provided, or 2) the City has certified that “adequate progress” has been made toward providing 200-year flood protection. Implementation measures focus on incorporating these specific requirements into the Lathrop Municipal Code. However, the GPA’s goals, policies, objectives and implementation measures also provide for continuing City participation in multi-agency flood prevention and emergency response programs and activities.

After approval of the GPA, as discussed above the Lathrop Municipal Code will need to be amended to be consistent with the LGP as amended by the GPA, and to meet zoning-specific requirements of the SB 5 Bills. Staff will prepare these documents for consideration by the Planning Commission and City Council in 2016.

City of Lathrop SB-5 200 Year Flood Protection General Plan Amendment

Contact Information