This measure would recognize the importance of the Diablo Range as a unique landscape deserving of amplified consideration, and would commend and support the Natural Resources Agency and its departments, organizational stakeholders, and individuals across the state in their collective efforts to elevate awareness involving the benefits and values of the Diablo Range.

This measure would recognize the importance of the Diablo Range as a unique landscape deserving of amplified consideration, and would commend and support the Natural Resources Agency and its departments, organizational stakeholders, and individuals across the state in their collective efforts to elevate awareness involving the benefits and values of the Diablo Range.

This measure would recognize the importance of the Diablo Range as a unique landscape deserving of amplified consideration, and would commend the Natural Resources Agency and its departments, organizational stakeholders, and individuals across the state in their collective efforts to elevate awareness involving the benefits and values of the Diablo Range.

WHEREAS, The Diablo Range is a unique landscape providing benefits relating to wildlife, recreation, agriculture, water resources, scenic views, climate, and other natural infrastructure and cultural benefits. The Diablo Range extends from the Carquinez Strait and Mount Diablo in the north, to Orchard Peak, Polonio Pass, Antelope Valley, and State Route 46 in the south, and is bounded on the west by the San Francisco Bay, the Santa Clara Valley, State Route 101, and the Salinas Valley, and on the east by the San Joaquin River and the San Joaquin Valley, and State Route 5; and

WHEREAS, The Diablo Range is 200 miles long and runs through the Counties of Alameda, Contra Costa, Fresno, Kern, Kings, Merced, Monterey, San Benito, San Joaquin, San Luis Obispo, Santa Clara, and Stanislaus; and

WHEREAS, The Diablo Range is bounded by, and includes, several of the fastest growing cities in California, including the Cities of Brentwood, Dublin, Lathrop, Hollister, Morgan Hill, and San Jose; and

WHEREAS, The Diablo Range encompasses more than 3,500,000 acres of diverse lands; and

WHEREAS, The Diablo Range is an intact wildlife habitat corridor of statewide significance supporting species such as the California condor, tule elk, golden eagle, mountain lion, and blunt-nosed leopard lizard, as well as endemic plants like the Mount Diablo globe lily; and

WHEREAS, The Diablo Range provides a critical corridor for wildlife migrating north through the Altamont Pass to Mount Diablo; west to the Santa Lucia Range, Big Sur, and the Santa Cruz Mountains; and south to the Carrizo Plain and the Tehachapi Mountains; and

WHEREAS, Over 10,000,000 people reside in communities around the Diablo Range and therefor, in addition to the mountain ranges rich biodiversity, it has also been identified as a new and largely untapped recreational resource to serve the growing adjacent populations; and

WHEREAS, Residents of the San Francisco Bay area, the Salinas Valley, and the San Joaquin Valley access the outdoors in the Diablo Range to view wildlife, recreate, and connect with nature and their communities; and

WHEREAS, The Diablo Range affords California one of its best opportunities to meet the states goal to conserve 30 percent of Californias lands and coastal waters by 2030, known as the 30x30 goal, and to address the climate crisis, by strategic land management and conservation practices to, among other important objectives, help more Californians connect with nature; and

WHEREAS, Natural resources of the Diablo Range provide opportunities for many climate and natural infrastructure benefits, including flood attenuation from improved wetlands, increased water supply from groundwater recharge, and carbon sequestration from natural and working lands; and

WHEREAS, The protection of the Diablo Range is a component of state and local efforts to preserve agriculture in California, and state investments from the Sustainable Agricultural Lands Conservation Program implemented by the Department of Conservation benefit the Diablo Range; and

WHEREAS, The Diablo Range contains significant cultural resources important to native people and the history of California: and

WHEREAS, The Diablo Range, given its expansive geography and its proximity to population centers, calls for an elevated vigilance and investment in landscape level vegetative treatments and management to reduce fire threats and resultant air quality implications; and

WHEREAS, Recognizing the Diablo Range as a California conservation priority will build momentum for future efforts and considerations to designate the Diablo Range as a national monument; and

WHEREAS, Recognizing the Diablo Ranges significance, over sixty organizations and agencies gathered on June 5, 2025, for the first annual Diablo Range Convening in the City of San Juan Bautista to increase awareness and collaborations required to protect this mountain range of statewide significance; now, therefore, be it

Resolved by the Assembly of the State of California, the Senate thereof concurring, That the Legislature recognizes the importance of the Diablo Range as a unique landscape deserving of amplified consideration and commends and supports the Natural Resources Agency and its departments, organizational stakeholders, and individuals across the state in their collective efforts to elevate awareness involving the benefits and values of the Diablo Range; and be it further

Resolved, That the Chief Clerk of the Assembly transmit copies of this resolution to the author for appropriate distribution.

WHEREAS, The Diablo Range is a unique landscape providing benefits relating to wildlife, recreation, agriculture, water resources, scenic views, climate, and other natural infrastructure and cultural benefits. The Diablo Range extends from the Carquinez Strait and Mount Diablo in the north, to Orchard Peak, Polonio Pass, Antelope Valley, and State Route 46 in the south, and is bounded on the west by the San Francisco Bay, the Santa Clara Valley, State Route 101, and the Salinas Valley, and on the east by the San Joaquin River and the San Joaquin Valley, and State Route 5; and

WHEREAS, The Diablo Range is 200 miles long and runs through the Counties of Alameda, Contra Costa, Fresno, Kern, Kings, Merced, Monterey, San Benito, San Joaquin, San Luis Obispo, Santa Clara, and Stanislaus; and

WHEREAS, The Diablo Range is bounded by, and includes, several of the fastest growing cities in California, including the Cities of Brentwood, Dublin, Lathrop, Hollister, Morgan Hill, and San Jose; and

WHEREAS, The Diablo Range encompasses more than 3,500,000 acres of diverse lands; and

WHEREAS, The Diablo Range is an intact wildlife habitat corridor of statewide significance supporting species such as the California condor, tule elk, golden eagle, mountain lion, and blunt-nosed leopard lizard, as well as endemic plants like the Mount Diablo globe lily; and

WHEREAS, The Diablo Range provides a critical corridor for wildlife migrating north through the Altamont Pass to Mount Diablo; west to the Santa Lucia Range, Big Sur, and the Santa Cruz Mountains; and south to the Carrizo Plain and the Tehachapi Mountains; and

WHEREAS, Over 10,000,000 people reside in communities around the Diablo Range and therefor, in addition to the mountain ranges rich biodiversity, it has also been identified as a new and largely untapped recreational resource to serve the growing adjacent populations; and

WHEREAS, Residents of the San Francisco Bay area, the Salinas Valley, and the San Joaquin Valley access the outdoors in the Diablo Range to view wildlife, recreate, and connect with nature and their communities; and

WHEREAS, The Diablo Range affords California one of its best opportunities to meet the states goal to conserve 30 percent of Californias lands and coastal waters by 2030, known as the 30x30 goal, and to address the climate crisis, by strategic land management and conservation practices to, among other important objectives, help more Californians connect with nature; and

WHEREAS, Natural resources of the Diablo Range provide opportunities for many climate and natural infrastructure benefits, including flood attenuation from improved wetlands, increased water supply from groundwater recharge, and carbon sequestration from natural and working lands; and

WHEREAS, The protection of the Diablo Range is a component of state and local efforts to preserve agriculture in California, and state investments from the Sustainable Agricultural Lands Conservation Program implemented by the Department of Conservation benefit the Diablo Range; and

WHEREAS, The Diablo Range contains significant cultural resources important to native people and the history of California: and

WHEREAS, The Diablo Range, given its expansive geography and its proximity to population centers, calls for an elevated vigilance and investment in landscape level vegetative treatments and management to reduce fire threats and resultant air quality implications; and

WHEREAS, Recognizing the Diablo Range as a California conservation priority will build momentum for future efforts and considerations to designate the Diablo Range as a national monument; and

WHEREAS, Recognizing the Diablo Ranges significance, over sixty organizations and agencies gathered on June 5, 2025, for the first annual Diablo Range Convening in the City of San Juan Bautista to increase awareness and collaborations required to protect this mountain range of statewide significance; now, therefore, be it

Resolved by the Assembly of the State of California, the Senate thereof concurring, That the Legislature recognizes the importance of the Diablo Range as a unique landscape deserving of amplified consideration and commends and supports the Natural Resources Agency and its departments, organizational stakeholders, and individuals across the state in their collective efforts to elevate awareness involving the benefits and values of the Diablo Range; and be it further

Resolved, That the Chief Clerk of the Assembly transmit copies of this resolution to the author for appropriate distribution.

WHEREAS, The Diablo Range is a unique landscape providing benefits relating to wildlife, recreation, agriculture, water resources, scenic views, climate, and other natural infrastructure and cultural benefits. The Diablo Range extends from the Carquinez Strait and Mount Diablo in the north, to Orchard Peak, Polonio Pass, Antelope Valley, and State Route 46 in the south, and is bounded on the west by the San Francisco Bay, the Santa Clara Valley, State Route 101, and the Salinas Valley, and on the east by the San Joaquin River and the San Joaquin Valley, and State Route 5; and

WHEREAS, The Diablo Range is 200 miles long and runs through the Counties of Alameda, Contra Costa, Fresno, Kern, Kings, Merced, Monterey, San Benito, San Joaquin, San Luis Obispo, Santa Clara, and Stanislaus; and

WHEREAS, The Diablo Range is bounded by, and includes, several of the fastest growing cities in California, including the Cities of Brentwood, Dublin, Lathrop, Hollister, Morgan Hill, and San Jose; and

WHEREAS, The Diablo Range encompasses more than 3,500,000 acres of diverse lands; and

WHEREAS, The Diablo Range is an intact wildlife habitat corridor of statewide significance supporting species such as the California condor, tule elk, golden eagle, mountain lion, and blunt-nosed leopard lizard, as well as endemic plants like the Mount Diablo globe lily; and

WHEREAS, The Diablo Range provides a critical corridor for wildlife migrating north through the Altamont Pass to Mount Diablo; west to the Santa Lucia Range, Big Sur, and the Santa Cruz Mountains; and south to the Carrizo Plain and the Tehachapi Mountains; and

WHEREAS, Over 10,000,000 people reside in communities around the Diablo Range and therefor, in addition to the mountain ranges rich biodiversity, it has also been identified as a new and largely untapped recreational resource to serve the growing adjacent populations; and

WHEREAS, Residents of the San Francisco Bay area, the Salinas Valley, and the San Joaquin Valley access the outdoors in the Diablo Range to view wildlife, recreate, and connect with nature and their communities; and

WHEREAS, The Diablo Range affords California one of its best opportunities to meet the states goal to conserve 30 percent of Californias lands and coastal waters by 2030, known as the 30x30 goal, and to address the climate crisis, by strategic land management and conservation practices to, among other important objectives, help more Californians connect with nature; and

WHEREAS, Natural resources of the Diablo Range provide opportunities for many climate and natural infrastructure benefits, including flood attenuation from improved wetlands, increased water supply from groundwater recharge, and carbon sequestration from natural and working lands; and

WHEREAS, The protection of the Diablo Range is a component of state and local efforts to preserve agriculture in California, and state investments from the Sustainable Agricultural Lands Conservation Program implemented by the Department of Conservation benefit the Diablo Range; and

WHEREAS, The Diablo Range contains significant cultural resources important to native people and the history of California: and

WHEREAS, The Diablo Range, given its expansive geography and its proximity to population centers, calls for an elevated vigilance and investment in landscape level vegetative treatments and management to reduce fire threats and resultant air quality implications; and

WHEREAS, Recognizing the Diablo Range as a California conservation priority will build momentum for future efforts and considerations to designate the Diablo Range as a national monument; and

WHEREAS, Recognizing the Diablo Ranges significance, over sixty organizations and agencies gathered on June 5, 2025, for the first annual Diablo Range Convening in the City of San Juan Bautista to increase awareness and collaborations required to protect this mountain range of statewide significance; now, therefore, be it

Resolved by the Assembly of the State of California, the Senate thereof concurring, That the Legislature recognizes the importance of the Diablo Range as a unique landscape deserving of amplified consideration and commends and supports the Natural Resources Agency and its departments, organizational stakeholders, and individuals across the state in their collective efforts to elevate awareness involving the benefits and values of the Diablo Range; and be it further

Resolved, That the Chief Clerk of the Assembly transmit copies of this resolution to the author for appropriate distribution.

 THIRD READING  

Bill No: ACR 107

Author: Bauer-Kahan (D)

Introduced: 7/15/25

Vote: 21

SENATE NATURAL RES. & WATER COMMITTEE: 7-0, 6/9/26

AYES: Becker, Seyarto, Allen, Cabaldon, Grove, Laird, Reyes

ASSEMBLY FLOOR: 74-0, 9/13/25 (Consent) - See last page for vote

SUBJECT: The Diablo Range

SOURCE: Author

DIGEST:

This resolution (1) recognizes the importance of the Diablo Range as a unique landscape deserving of amplified consideration, and (2) commends the Natural Resources Agency (CNRA) and its departments, organizational stakeholders, and individuals across the state in their collective efforts to elevate awareness involving the benefits and values of the Diablo Range.

ANALYSIS:

Existing Law:

1. Directs CNRA to combat the biodiversity and climate crisis by, among other things, establishing the California Biodiversity Collaborative and establishing the 30x30 goal (Executive Order No. N-82-20).
2. Codifies the 30x30 goal (Public Resources Code § 71450).
3. Declares that it is a national policy to preserve for public use historic sites, buildings, and objects of national significance for the inspiration and benefit of the people of the United States (54 United States Code (USC) § 320101).

This resolution:

1. Makes a number of findings, including:
   1. The Diablo Range encompasses more than 3.5 million acres of diverse lands;
   2. The Diablo Range is an intact wildlife habitat corridor of statewide significance supporting species such as the California condor, tule elk, golden eagle, mountain lion, and blunt-nosed leopard lizard, as well as endemic plants like the Mount Diablo globe lily;
   3. Over 10 million people reside in communities around the Diablo Range and therefore, in addition to the mountain range’s rich biodiversity, it has also been identified as a new and largely untapped recreational resource to serve the growing adjacent populations;
   4. The Diablo Range affords California one of its best opportunities to meet the state’s goal to conserve 30% of California’s lands and coastal waters by 2030 (i.e., the 30x30 goal) and to address the climate crisis, by strategic land management and conservation practices to help more Californians connect with nature;
   5. The Diablo Range contains significant cultural resources important to native people and the history of California; and
   6. Recognizing the Diablo Range as a California conservation priority will build momentum for future efforts and considerations to designate the Diablo Range as a national monument.
2. Resolves that:
   1. The Legislature recognizes the importance of the Diablo Range as a unique landscape deserving of amplified consideration; and
   2. Commends and supports CNRA and its departments, organizational stakeholders, and individuals across the state in their collective efforts to elevate awareness involving the benefits and values of the Diablo Range.

Background

Diablo Mountain Range. According to the Assembly Water, Parks, and Wildlife Committee, California’s Diablo Mountain Range sits within the Central California Foothills and Coastal Mountains ecoregion, which has a Mediterranean climate and associated vegetation communities of grassland, chaparral, and oak woodlands. The Diablo Range stretches from the eastern San Francisco Bay area to State Route 46, passing through Contra Costa, Alameda, San Joaquin, Santa Clara, Stanislaus, Merced, San Benito, Fresno, Monterey, Kings, San Luis Obispo, and Kern counties. The range is named after Mount Diablo in Contra Costa County. According to the Save Mount Diablo (SMD) website, the Diablo Range covers 5,400 square miles and has many peaks, some of which are taller than Mount Diablo with the tallest peak being San Benito Mountain at 5,241 feet.

National Monuments. This resolution notes that the Diablo Range, given its critical wildlife habitat corridors, natural resources, cultural significance, and proximity to population centers causing development pressures, calls for an elevated vigilance and investment in management projects to reduce fire threats. Additionally, it suggests that recognizing the Diablo Range as a California conservation priority will build momentum for efforts to designate the Diablo Range as a national monument.

The Federal Antiquities Act (act), passed in 1906, authorizes the President to establish national monuments. Specifically, the act gives the President the authority to “declare by public proclamation historic landmarks, historic and prehistoric structures, and other objects of historic or scientific interest that are situated on land owned or controlled by the Federal Government to be national monuments” (54 USC § 320301(a)). National monuments may be administered by the National Park Service, the U.S. Forest Service, the U.S. Fish and Wildlife Service, or the Bureau of Land Management. Since 1906, U.S. presidents have used their authority under the Antiquities Act to set aside land almost 300 times.

In California, there are nearly 20 national monuments, including Berryessa Snow Mountain, Cabrillo, California Coastal, Carrizo Plain, Castle Mountains, César E. Chávez, Devils Postpile, Fort Ord, Giant Sequoia, Lava Beds, Mojave Trails, Muir Woods, Saint Francis Dam Disaster, Sand to Snow, San Gabriel Mountains, Santa Rosa and San Jacinto Mountains, and Tule Lake.

Related/Prior Legislation

AB 1426 (Kalra, Bauer-Kahan, 2025) of the current legislative session, would have required the Wildlife Conservation Board to establish the Diablo Range Conservation Program. AB 1426 was held in the Assembly Appropriations Committee.

SJR 16 (Padilla, Chapter 208, Statutes of 2024), urges the President to use the Antiquities Act of 1906 to establish the Chuckwalla, Joshua Tree, and Kw’tsán National Monuments.

SJR 17 (Allen, Chapter 209, Statutes of 2024), urges the President to use the Antiquities Act of 1906 to establish the Sáttítla National Monument.

FISCAL EFFECT: Appropriation: No Fiscal Com.: No Local: No

SUPPORT: (Verified 6/9/26)

Californians for Western Wilderness
East Contra Costa County Habitat Conservancy
Fresno Chaffee Zoo
Golden Gate Bird Alliance
Institute for Historical Ecology
Livermore Hill Hikers
Mak-warép Ohlone Land Conservancy
Mount Diablo Bird Alliance
Protect San Benito
Santa Clara Valley Bird Alliance
Santa Clara Valley Habitat Agency
Save Mount Diablo
Sierra Club

OPPOSITION: (Verified 6/9/26)

None received

ARGUMENTS IN SUPPORT: According to the author, “The Diablo Range is one of California’s most ecologically and recreationally significant landscapes. The range is home to many diverse habitats that support hundreds of native plant and wildlife species, including rare and threatened species found nowhere else in the world. This range also serves as a crucial wildlife corridor, connecting ecosystems across the state and strengthening the region’s climate reliance. Beyond its ecological value, the Diablo Range provides critical natural benefits such as clean water, carbon storage, and expansive open space that supports recreation and public enjoyment. Recognizing the Diablo Range as a priority for conservation ensures the protection of its biodiversity, ecosystems, and natural resources for generations to come.”

ASSEMBLY FLOOR: 74-0, 9/13/25

AYES: Addis, Aguiar-Curry, Ahrens, Alanis, Alvarez, Arambula, Ávila Farías, Bains, Bauer-Kahan, Bennett, Berman, Boerner, Bonta, Bryan, Calderon, Caloza, Carrillo, Castillo, Chen, Connolly, Davies, DeMaio, Dixon, Ellis, Fong, Gabriel, Gallagher, Garcia, Gipson, Jeff Gonzalez, Mark González, Hadwick, Haney, Harabedian, Hart, Hoover, Irwin, Jackson, Johnson, Kalra, Krell, Lackey, Lee, Lowenthal, Macedo, Muratsuchi, Nguyen, Ortega, Pacheco, Papan, Patel, Pellerin, Petrie-Norris, Quirk-Silva, Ramos, Ransom, Celeste Rodriguez, Michelle Rodriguez, Rogers, Blanca Rubio, Sanchez, Schiavo, Schultz, Sharp-Collins, Soria, Stefani, Tangipa, Valencia, Wallis, Ward, Wicks, Wilson, Zbur, Rivas

NO VOTE RECORDED: Elhawary, Flora, McKinnor, Patterson, Solache, Ta

Prepared by: Edith Hannigan / N.R. & W. / (916) 651-4116

6/10/26 16:52:25

**** END ****

SENATE COMMITTEE ON NATURAL RESOURCES AND WATER

Senator Josh Becker, Chair

2025 - 2026 Regular

Bill No: ACR Hearing Date: June 9, 2026

Subject: The Diablo Range

SUMMARY

This measure would recognize the importance of the Diablo Range as a unique landscape deserving of amplified consideration, and would commend the California Natural Resources Agency (CNRA) and its departments, organizational stakeholders, and individuals across the state in their collective efforts to elevate awareness involving the benefits and values of the Diablo Range.

BACKGROUND AND EXISTING LAW

Diablo Mountain Range. According to the Assembly Water, Parks, and Wildlife Committee, California’s Diablo Mountain Range sits within the Central California Foothills and Coastal Mountains ecoregion, which has a Mediterranean climate and associated vegetation communities of grassland, chaparral, and oak woodlands. The Diablo Range stretches from the eastern San Francisco Bay area to State Route 46, passing through Contra Costa, Alameda, San Joaquin, Santa Clara, Stanislaus, Merced, San Benito, Fresno, Monterey, Kings, San Luis Obispo, and Kern counties. The range is named after Mount Diablo in Contra Costa County. According to the Save Mount Diablo (SMD) website, the Diablo Range covers 5,400 square miles and has many peaks, some of which are taller than Mount Diablo with the tallest peak being San Benito Mountain at 5,241 feet.

Boundary of the Diablo Range from SMD. This range includes Pinnacles National Park, Mount Diablo State Park, Henry W. Coe State Park, and Pacheco State Park. A more detailed map of land holdings is available in SMD’s 2023–2024 annual report.

Existing Law:

1. Directs CNRA to combat the biodiversity and climate crisis by, among other things, establishing the California Biodiversity Collaborative and establishing the 30x30 goal (Executive Order No. N-82-20).
2. Codifies the 30x30 goal (Public Resources Code § 71450).
3. Declares that it is a national policy to preserve for public use historic sites, buildings, and objects of national significance for the inspiration and benefit of the people of the United States [54 United States Code (USC) § 320101].

PROPOSED LAW

1. Makes a number of findings, including:
   1. The Diablo Range encompasses more than 3,500,000 acres of diverse lands;
   2. The Diablo Range is an intact wildlife habitat corridor of statewide significance supporting species such as the California condor, tule elk, golden eagle, mountain lion, and blunt-nosed leopard lizard, as well as endemic plants like the Mount Diablo globe lily;
   3. Over 10 million people reside in communities around the Diablo Range and therefore, in addition to the mountain range’s rich biodiversity, it has also been identified as a new and largely untapped recreational resource to serve the growing adjacent populations;
   4. The Diablo Range affords California one of its best opportunities to meet the state’s goal to conserve 30% of California’s lands and coastal waters by 2030 (i.e., the 30x30 goal) and to address the climate crisis, by strategic land management and conservation practices to help more Californians connect with nature;
   5. The Diablo Range contains significant cultural resources important to native people and the history of California; and
   6. Recognizing the Diablo Range as a California conservation priority will build momentum for future efforts and considerations to designate the Diablo Range as a national monument.
2. Resolves that:
   1. The Legislature recognizes the importance of the Diablo Range as a unique landscape deserving of amplified consideration; and
   2. Commends and supports CNRA and its departments, organizational stakeholders, and individuals across the state in their collective efforts to elevate awareness involving the benefits and values of the Diablo Range.

ARGUMENTS IN SUPPORT

According to the author, “The Diablo Range is one of California’s most ecologically and recreationally significant landscapes. The range is home to many diverse habitats that support hundreds of native plant and wildlife species, including rare and threatened species found nowhere else in the world. This range also serves as a crucial wildlife corridor, connecting ecosystems across the state and strengthening the region’s climate reliance. Beyond its ecological value, the Diablo Range provides critical natural benefits such as clean water, carbon storage, and expansive open space that supports recreation and public enjoyment. Recognizing the Diablo Range as a priority for conservation ensures the protection of its biodiversity, ecosystems, and natural resources for generations to come.”

ARGUMENTS IN OPPOSITION

None received.

COMMENTS

National Monuments. This resolution notes that the Diablo Range, given its critical wildlife habitat corridors, natural resources, cultural significance, and proximity to population centers causing development pressures, calls for an elevated vigilance and investment in management projects to reduce fire threats. Additionally, it suggests that recognizing the Diablo Range as a California conservation priority will build momentum for efforts to designate the Diablo Range as a national monument.

The Federal Antiquities Act (act), passed in 1906, authorizes the President to establish national monuments. Specifically, the act gives the President the authority to “declare by public proclamation historic landmarks, historic and prehistoric structures, and other objects of historic or scientific interest that are situated on land owned or controlled by the Federal Government to be national monuments” [54 USC § 320301(a)]. National monuments may be administered by the National Park Service, the U.S. Forest Service, the U.S. Fish and Wildlife Service, or the Bureau of Land Management. Since 1906, U.S. presidents have used their authority under the Antiquities Act to set aside land almost 300 times.

In California, there are nearly 20 national monuments, including Berryessa Snow Mountain, Cabrillo, California Coastal, Carrizo Plain, Castle Mountains, César E. Chávez, Devils Postpile, Fort Ord, Giant Sequoia, Lava Beds, Mojave Trails, Muir Woods, Saint Francis Dam Disaster, Sand to Snow, San Gabriel Mountains, Santa Rosa and San Jacinto Mountains, and Tule Lake.

Related Legislation

AB 1426 (Kalra, Bauer-Kahan) of the current legislative session, would have required the Wildlife Conservation Board to establish the Diablo Range Conservation Program. AB 1426 was held in the Assembly Appropriations Committee.

SJR 16 (Padilla, Chapter 208, Statutes of 2024), urges the President to use the Antiquities Act of 1906 to establish the Chuckwalla, Joshua Tree, and Kw’tsán National Monuments.

SJR 17 (Allen, Chapter 209, Statutes of 2024), urges the President to use the Antiquities Act of 1906 to establish the Sáttítla National Monument.

SUGGESTED AMENDMENTS: none

SUPPORT

East Contra Costa County Habitat Conservancy
Golden Gate Bird Alliance
Institute for Historical Ecology
Protect San Benito
Save Mount Diablo

OPPOSITION

None Received

-- END --

Date of Hearing: September 10, 2025

ASSEMBLY COMMITTEE ON WATER, PARKS, AND WILDLIFE

Diane Papan, Chair

ABPCA Bill Id:ACR 107 (

Author:Bauer-Kahan) – As Introduced Ver:July 15, 2025

SUBJECT: The Diablo Range

SUMMARY: Resolves that the Legislature recognizes the importance of the Diablo Range and commends and supports the California Natural Resources Agency (CNRA), organizational stakeholders, and individuals in their collective efforts to elevate awareness of the benefits and values of the Diablo Range. Specifically, this bill:

1. Makes a number of findings, including:
   1. The Diablo Range encompasses more than 3,500,000 acres of diverse lands;
   2. The Diablo Range is an intact wildlife habitat corridor of statewide significance supporting species such as the California condor, tule elk, golden eagle, mountain lion, and blunt-nosed leopard lizard, as well as endemic plants like the Mount Diablo globe lily;
   3. Over 10 million people reside in communities around the Diablo Range and therefore, in addition to the mountain range’s rich biodiversity, it has also been identified as a new and largely untapped recreational resource to serve the growing adjacent populations;
   4. The Diablo Range affords California one of its best opportunities to meet the state’s goal to conserve 30% of California’s lands and coastal waters by 2030 (i.e., the 30x30 goal) and to address the climate crisis, by strategic land management and conservation practices to help more Californians connect with nature;
   5. The Diablo Range contains significant cultural resources important to native people and the history of California; and
   6. Recognizing the Diablo Range as a California conservation priority will build momentum for future efforts and considerations to designate the Diablo Range as a national monument;

EXISTING LAW:

1. Directs CNRA to combat the biodiversity and climate crisis by, among other things, establishing the California Biodiversity Collaborative and establishing the 30x30 goal (Executive Order No. N-82-20).
2. Codifies the 30x30 goal (Public Resources Code § 71450).
3. Declares that it is a national policy to preserve for public use historic sites, buildings, and objects of national significance for the inspiration and benefit of the people of the United States [54 United States Code (USC) § 320101].

FISCAL EFFECT: This resolution is keyed non-fiscal.

COMMENTS:

1. Purpose of this bill. According to the author, “The Diablo Range is one of California’s most ecologically and recreationally significant landscapes. The range is home to many diverse habitats that support hundreds of native plant and wildlife species, including rare and threatened species found nowhere else in the world. This range also serves as a crucial wildlife corridor, connecting ecosystems across the state and strengthening the region’s climate resilience. Beyond its ecological value, the Diablo Range provides critical natural benefits such as clean water, carbon storage, and expansive open space that supports recreation and public enjoyment. Recognizing the Diablo Range as a conservation priority ensures the protection of its biodiversity, ecosystems, and natural resources for generations to come.”
2. Background. California’s Diablo Mountain Range sits within the Central California Foothills and Coastal Mountains ecoregion, which has a Mediterranean climate and associated vegetation communities of grassland, chaparral, and oak woodlands. The Diablo Range stretches from the eastern San Francisco Bay area to State Route 46, passing through Contra Costa, Alameda, San Joaquin, Santa Clara, Stanislaus, Merced, San Benito, Fresno, Monterey, Kings, San Luis Obispo, and Kern counties. The range is named after Mount Diablo in Contra Costa County. According to the Save Mount Diablo (SMD) website, the Diablo Range covers 5,400 square miles and has many peaks, some of which are taller than Mount Diablo with the tallest peak being San Benito Mountain at 5,241 feet.

The SMD website states that the range is extremely important for wildlife and it is crossed only by two major highways at Altamont and Pacheco Passes. It is core habitat for wildlife in California and is responsible for providing California with a stable golden eagle population, despite that species’ decline in the rest of western North America. Tule elk, nearly hunted to extinction in the 1970s, have recovered quickly in the Diablo Range. Bay checkerspot butterflies have their last stronghold along Coyote Ridge just above San Jose. SMD also indicates that the Diablo Range offers great habitat for California condors to expand into as they recover from the brink of extinction and could also be the source for replenishing the genetic diversity of mountain lion populations in the Santa Cruz Mountains.

SMD also indicates that the Diablo Range is threatened by energy development (both alternative and fossil fuel-based energy), suburban sprawl, and proposed dams and reservoirs. Wind turbines endanger golden eagles and other birds. The Panoche Valley, part of the Diablo Range, now has a 4,800-acre solar farm.

Boundary of the Diablo Range from SMD. This range includes Pinnacles National Park, Mount Diablo State Park, Henry W. Coe State Park, and Pacheco State Park. A more detailed map of land holdings is available in SMD’s 2023–2024 annual report.

National Monuments. As declared in this resolution, there is a desire among some to “build momentum for future efforts and considerations to designate the Diablo Range as a national monument.” The Federal Antiquities Act, passed in 1906, seeks to preserve America’s archaeological places and historical sites, including the information they contain, on federal lands. Among other things, this act authorizes the President to establish national monuments. Specifically, the act gives the President the authority to “declare by public proclamation historic landmarks, historic and prehistoric structures, and other objects of historic or scientific interest that are situated on land owned or controlled by the Federal Government to be national monuments” [54 USC § 320301(a)]. National monuments may be administered by the National Park Service, the U.S. Forest Service, the U.S. Fish and Wildlife Service, or the Bureau of Land Management. Since 1906, U.S. presidents have used their authority under the Antiquities Act to set aside land almost 300 times.

In California, there are nearly 20 national monuments, including Berryessa Snow Mountain, Cabrillo, California Coastal, Carrizo Plain, Castle Mountains, César E. Chávez, Devils Postpile, Fort Ord, Giant Sequoia, Lava Beds, Mojave Trails, Muir Woods, Saint Francis Dam Disaster, Sand to Snow, San Gabriel Mountains, Santa Rosa and San Jacinto Mountains, and Tule Lake. On January 14, 2025, President Biden established both Chuckwalla and Sáttítla National Monuments. In May 2025, the U.S. Department of Justice issued a legal opinion asserting that the President can alter the boundaries or abolish national monuments. This opinion overturns an Attorney General opinion from 1938 and is a threat to California’s public land.

1. Related legislation. AB 1426 (Kalra, Bauer-Kahan) of the current legislative session, would have required the Wildlife Conservation Board to establish the Diablo Range Conservation Program. AB 1426 was held in the Assembly Appropriations Committee.

SJR 16 (Padilla), Chapter 208, of 2024, urges the President to use the Antiquities Act of 1906 to establish the Chuckwalla, Joshua Tree, and Kw’tsán National Monuments.

SJR 17 (Allen), Chapter 209, of 2024, urges the President to use the Antiquities Act of 1906 to establish the Sáttítla National Monument.

REGISTERED SUPPORT / OPPOSITION:

Support

None on file

Opposition

None on file

Analysis Prepared by: Stephanie Mitchell / W., P., & W. / (916) 319-2096