Section 15153 CEQA Initial Study submittal for the Contra Costa County 2026 Urban Limit Line Renewal
The proposed project is a 2026 Ballot Measure asking the voters of Contra Costa County to amend the Land Use Element of the Contra Costa County 2045 General Plan and the 65/35 Contra Costa Land Preservation Plan Ordinance (Chapter 82-1 of the County Ordinance Code) to to extend the Urban Limit Line (ULL) and 65/35 Plan term through December 2051, modify the ULL periodic review requirement, make revisions to the adopted ULL map, and make other changes to the language in the Ordinance and findings for the ULL adjustment process.
Project Summary
The proposed project is a 2026 ballot measure asking Contra Costa County voters to amend the Land Use Element of the 2045 General Plan and the 65/35 Contra Costa Land Preservation Plan Ordinance (Chapter 82-1 of the County Ordinance Code) to:
1. Extend the term of the 65/35 Land Preservation Plan Ordinance (Chapter 82-1 of the County Ordinance Code) and the Countys Urban Limit Line through December 31, 2051.
2. Modify the periodic ULL review requirements of the 65/35 Land Preservation Plan Ordinance (Chapter 82-1 of the County Ordinance Code) to require review of the ULL boundary concurrently with State-mandated Housing Element update cycles.
3. Modify the criteria and factors enumerated in the 65/35 Land Preservation Plan Ordinance (Chapter 82-1 of the County Ordinance Code) for determining whether land should be considered for placement outside the ULL, to include:
a. Lands which qualify for rating as Class I or Class II in the Soil Conservation Service Land Use Capability Classification.
b. Lands designated as High or Very High Fire Hazard Severity Zones on maps published by the California Department of Forestry and Fire Protection.
c. Lands with slopes of 26 percent or greater.
d. Lands at risk from substantial inundation due to flooding or anticipated sea level rise.
e. Lands with recorded development restrictions such as agricultural, conservation, or
scenic easements or deeded development rights.
f. Open space, parks, and other recreation areas.
g. Wetlands and undevelopable islands.
h. Areas with inadequate water, sewer, and roadway infrastructure.
i. Other areas not appropriate for urban growth because of separation from existing
development, unstable geologic conditions, likelihood of substantial environmental damage or substantial injury to fish or wildlife or their habitat, and other similar factors rendering the land physically unsuitable for intense development.
4. Retain, during the extended term of the 65/35 Land Preservation Plan Ordinance (Chapter 82-1 of the County Ordinance Code) and the Countys Urban Limit Line, the requirement for voter approval to expand the Countys Urban Limit Line by more than 30 acres, except as specifically authorized in the 65/35 Land Preservation Plan Ordinance, and approved by the voters in this ballot measure, namely:
a. The Board of Supervisors may, without subsequent voter approval, expand the ULL by any acreage within the boundaries of the Byron Airport Potential ULL Expansion
illustrated on General Plan Land Use Element Figure LU-2, Urban Limit Line, after holding a public hearing at which the Board adopts the General Plan amendment for the expansion, a four-fifths vote, after making each of the following findings based on
substantial evidence in the record:
i. The expansion is necessary to further the economic viability of Byron Airport and
attain the Countys goals related to economic development.
ii. The expanded ULL area will accommodate uses directly linked to aeronautics, such
as aviation research and development, aircraft manufacturing/assembly, and aeronautical schools/training facilities.
iii. The expanded ULL area will not accommodate residential development,
logistics/distributions centers, lodging, or any other use not directly linked to
aeronautics except for minor ancillary uses necessary to support the airport
workforce.
iv. The expansion will not induce sprawl.
5. Retain in both the General Plan and County Ordinance Code the requirement that a four-fifths vote of the Board of Supervisors is necessary to place a measure on the election ballot to expand the ULL boundary by more than 30 acres through the year 2051.
6. Retain in both the General Plan and County Ordinance Code the existing procedure for any change to the Countys ULL under 30 acres based on a four-fifths vote of the Board of Supervisors after holding a public hearing and making at least one of seven findings, as proscribed in both the General Plan and County Ordinance Code, based on substantial evidence in the record.
7. Modify the enumerated findings proscribed in both the General Plan and County Ordinance Code required for a change to the Countys ULL under 30 acres to reflect the modified periodic ULL reviews and to make other non-substantive changes.
8. Retain the 65/35 standard for land preservation in Contra Costa County, whereby at least 65 percent of the overall county land area will be retained for non-urban uses through the year 2051.
9. Retain the protections for the countys prime agricultural land, specifically the area designated in the General Plan as the Agricultural Core, by maintaining the 40-acre
minimum parcel size.
10. Approve a new ULL Map for the General Plan (Figure LU-2 in the 2045 General Plan Land Use Element), which reflects the following changes:
a. Moves 3,487 acres with significant development restrictions, such as ownership by government agencies or encumbrance with conservation or agricultural easements, outside the ULL.
b. Moves 1,488 acres of buffer lands around subdivisions, cemeteries, and industrial facilities, outside the ULL.
c. Moves 4,368 acres with significant development constraints, such as high fire hazards, steep slopes, and flood hazards, outside the ULL.
d. Moves 873 acres outside the ULL and 923 acres inside the ULL to align the ULL with city limits.
e. Moves 847 acres outside the ULL and 421 acres inside the ULL to simplify and improve understanding of the ULL along the countys shoreline.
The proposed adjustments to the ULL Map are shown in Figure 3, Proposed Urban Limit Line.
11. Update administrative sections of the 65/35 Land Preservation Ordinance to correct outdated text and achieve consistency with the changes described in items 1-10 above.
