California Code of Regulations › Title 14 - Natural Resources › Division 9 - Delta Protection Commission › Chapter 3 - Regulations Governing Land Use and Resource Management in the Primary Zone of the Sacramento-San Joaquin Delta › Section 20040 - Natural Resources

Current through Register 2024 Notice Reg. No. 28, July 12, 2024
(a) Overview
The Delta is a unique geographic area in the State of
				  California, a low-lying region of rich mineral and peat soils, composed of
				  islands created largely by humans as they diked and drained the prehistoric
				  marshes of the region. The geology of the region created this unique "Delta".
				  Sediments trapped inland of the rocky neck of the Carquinez Straits resulted in
				  the creation of this 1,100 square-mile area. Based on the geological
				  characteristics of the Delta, there is potential for seismic activity in the
				  region.
The peat soils of the central and western Delta have
				  oxidized, resulting in subsidence of land surfaces of up to 20 feet. Original
				  peat soil depths varied substantially from area to area and even within a given
				  island. Subsidence has slowed to about one-third of an inch a year in many
				  areas. Flood threats are compounded by the low elevations of the Delta and by
				  subsidence. Twice in each approximately 25-hour period the elevation of the
				  Sacramento River rises and falls about three feet due to the tidal cycle. The
				  threat of flooding is generally associated with periods of high winter rainfall
				  and periods of rapid spring snow melt in the watersheds draining into the
				  Delta. The most critical conditions occur when upstream darns are full and the
				  resulting high rates of river flow combine with high tides and strong
				  winds.
The lush wetland habitats surrounded by riparian woodlands
				  have been replaced by agricultural lands including cultivated and irrigated
				  croplands as well as irrigated and non-irrigated pasture lands. Remnants of
				  natural habitat are located largely along some sloughs and rivers and on small
				  channel islands. Pockets of wooded or wetland habitat exist on some
				  islands.
The aquatic habitats historically ranged from fresh to
				  brackish and were home to both resident and migratory fish. Modern aquatic
				  habitats are affected by flows released from upstream dams, seasonal drainage
				  from agricultural lands, and year-round drainage from sources outside the
				  Primary Zone. Several large, freshwater lakes are located on the eastern edge
				  of the Delta, providing year-round wetland habitat.
Species native to the Delta evolved within an ecosystem that
				  was much different than today. Many of the indigenous species have declined
				  because of ecosystem changes over the past 150 years including:
* Loss of habitat.
* Loss of access to upstream habitat for anadromous fish from
				  construction of dams.
* Diking and draining of Delta lands to convert marshes to
				  farms.
* Urbanization.
* Changes in river flows.
* Construction of levees that separate rivers from their
				  floodplains thereby eliminating channel meander and riparian habitat.
* Invasion by non-native species.
* Alterations in hydrology, particularly the elimination of
				  variability in seasonal flow patterns.
* Reduction in seasonal and annual variability in
				  salinity.
* Introduction of numerous toxic substances.
* Export pumping in the South Delta.
Flow patterns in the Delta are governed by inflows, large
				  water diversions, and tidal flows. The relative importance of these flows
				  varies with season and location. Net--tidally averaged--flows depend on inflows
				  from the rivers and export pumping in the southern Delta. Sometimes the
				  combination of inflows and exports causes "reverse flow," or a situation when
				  flow moves upstream rather than downstream. These flows can cause young fish,
				  including eggs and larvae, to be entrained at the pumping facilities of the
				  State Water Project and the Central Valley Project.
The Delta provides substantial habitat for resident and
				  migratory waterfowl and shorebirds. The abundance of these birds declined
				  precipitously in the Delta because of land reclamation, although subsequent
				  changes in cropping patterns have allowed populations of some species to
				  increase.
The Delta supports hundreds of fish, plants, mammals,
				  amphibians, reptiles, and invertebrates. Many of the native species have
				  declined in abundance and in range, leading to the listing of several species
				  under the California and/or federal Endangered Species Acts. Early species
				  declines were caused by loss or isolation of physical habitat when the Delta
				  islands were drained. However, due to the information collected as a result of
				  monitoring activities that occurred in the 1960's through the 1980's, it is
				  clear that species declined due to a variety of causes including changing
				  climate; effects of toxic substances; alteration of habitat; introduction of
				  non-native species that consume, compete with, or alter the habitat of native
				  species; water diversions/exports; and changes in hydrology.
In the past few years, the abundance of several pelagic (open
				  water) fish species inhabiting the Delta, such as delta smelt and longfin
				  smelt, have declined to record-low levels. The reasons for this pelagic
				  organism decline are multiple and are the subject of intense investigation. The
				  loss of pelagic species in the Delta seems to be a function of poor conditions
				  for food conditions, invasive species, degraded water quality, losses to export
				  pumping, and other potential negative influences, such as toxins. The
				  populations of salmon that migrate through the Delta and are dependent on Delta
				  resources have also experienced precipitous declines, which have adversely
				  affected the fishing industry.
Long-term trends for the ecosystem depend on the severity of
				  climate change and the future physical structure and salinity of the Delta.
				  Large mammals, such as bear and elk, which historically lived in and around the
				  Delta have either been eliminated or reduced to extremely low numbers. Aquatic
				  mammals, including beaver and otter still remain. Some resident and migratory
				  birds have adapted to the agricultural practices in the Delta, particularly the
				  small grain fields which are flooded in fall and winter months. Migratory birds
				  include ducks. geese, swans, cranes, and shorebirds. Hawks and eagles forage in
				  the Delta fields. The Primary Zone, with its large open expanses of farmland,
				  mosaic of small grain crop residues and shallow flooded fields, permit wildlife
				  to feed and rest, thereby providing high quality wildlife habitat.
It is recognized that Habitat Conservation Plans and Natural
				  Community Conservation Planning (HCP/NCCP) efforts within the Delta, including
				  the CALFED Ecosystem Restoration Program Plan (ERPP) 4, must be acknowledged in
				  the administration of the policies of the Plan as these programs include
				  agreements and/or contracts that have long-term provisions to sustain a durable
				  program.
(b) Goals
Preserve and protect the natural resources of the Delta.
				  Promote protection of remnants of riparian and aquatic habitat. Encourage
				  compatibility between agricultural practices and wildlife
				  habitat.
(c) Policies
(1) Preserve and protect the natural
				resources of the Delta. Promote protection of remnants of riparian and aquatic
				habitat. Encourage compatibility between agricultural practices, recreational
				uses and wildlife habitat.
(2)
				Encourage farmers to implement management practices to maximize habitat values
				for migratory birds and other wildlife. Appropriate incentives, such as:
				purchase of conservation easements from willing sellers or other actions,
				should be encouraged.
(3) Lands
				managed primarily for wildlife shall be managed to maximize ecological values.
				Appropriate programs, such as "Coordinated Resource Management and Planning"
				(Public Resources Code Section
				9408(c))
				should ensure full participation by local government and property owner
				representatives.
(4) Support the
				non-native invasive species control measures being implemented by the
				California Department of Fish and Game, the California Department of Boating
				and Waterways, the California Emergency Management Agency, the California
				Department of Food and Agriculture, the State Water Resources Control Board,
				the Central Valley and San Francisco Bay Regional Water Quality Control Boards,
				and the Agricultural Commissioners for the five Delta Counties (Yolo, Solano,
				Sacramento, San Joaquin, and Contra Costa), which include controlling the
				arrival of new species into the Delta.
(5) Preserve and protect the viability of
				agricultural areas by including an adequate financial mechanism in any planned
				conversion of agricultural lands to wildlife habitat for conservation purposes.
				The financial mechanism shall specifically offset the loss of local government
				and special district revenues necessary to support public services and
				infrastructure.
(6) Support the
				implementation of appropriate buffers, management plans and/or good neighbor
				policies (e.g. safe harbor agreements) that among other things, limit liability
				for incidental take associated with adjacent agricultural and recreational
				activities within lands converted to wildlife habitat to ensure the ongoing
				agricultural and recreational operations adjacent to the converted lands are
				not negatively affected.
(7)
				Incorporate, to the maximum extent feasible, suitable and appropriate wildlife
				protection, restoration and enhancement on publicly-owned land as part of a
				Delta-wide plan for habitat management.
(8) Promote ecological, recreational and
				agricultural tourism in order to preserve the cultural values and economic
				vitality that reflect the history, natural heritage and human resources of the
				Delta including the establishment of National Heritage Area
				designations.
(9) Protect and
				restore ecosystems and adaptively manage them to minimize impacts from climate
				change and other threats and support their ability to adapt in the face of
				stress.
(10) Ensure that design,
				construction, and management of any flooding program to provide seasonal
				wildlife and aquatic habitat on agricultural lands, duck club lands and
				additional seasonal and tidal wetlands, shall incorporate "best management
				practices" to minimize vectors including mosquito breeding opportunities, and
				shall be coordinated with the local vector control districts, (each of the four
				vector control districts in the Delta provides specific wetland/mosquito
				management criteria to landowners within their district.)