Comment letter on Oakley development from Greenbelt Alliance to the Army Corps of Engineers

November 25, 2006

William Guthrie, Project Manager
US Army Corps of Engineers, Sacramento District
Delta Office
1325 J Street, Room 1480
Sacramento, California 95814-2922

Re: Public Notice numbers: 2004400728, 200400729, 200400774, 200400902 (East Cypress corridor project, City of Oakley)

Dear Mr. Guthrie:

Thank you for extending the comment period and for the opportunity to comment on Public Notice numbers: 2004400728, 200400729, 200400774, 200400902 regarding the East Cypress Corridor Project in the City of Oakley.  Greenbelt Alliance urges the Army Corps of Engineers to conduct a full environmental impact study under the National Environmental Policy Act (NEPA) on the proposed project before issuing any permits.  The proposed development should prompt a NEPA review due to the scope and intensity of impacts on federally listed species, federal water and power facilities, and public health and safety, and on the United States’ water resources.

Water quality impacts
The project water supply is contingent on extension of the Central Valley Project Service Area which would require NEPA analysis on its own right.  Storm water drainage from the site will be discharged into the Delta, which is habitat to federally listed species and provides drinking water supply for 23 million Californians.  Water discharged from the site is likely to contain high concentrations of pollutants including heavy metals, hydrocarbons, excess nutrients and salts.  In addition to run-off from the newly developed specific plan area, continuous groundwater pumping to prevent inundation of the site could result in the discharge of brackish water or high nitrates into Dutch and Sandmound Sloughs.  The US Army Corps of Engineers should study how the pollution will affect wildlife, the environment and public health.

Loss of wetlands 
Proposed development of Planning Areas 1, 3, and 4 (see attached) would result in the placement of fill into approximately 68 acres of wetlands and waters falling under state and federal jurisdiction.  This represents nearly 61 percent of the total wetlands on site.  Although impacts to wetlands in Planning Areas 2 and 6 are not known, these lands support an additional 61 acres of wetlands.  By any standard, the filling of 68 acres of wetlands represents a very significant impact, and if permitted, is likely to represent one of the largest impacts to wetlands in Contra Costa County.

Additionally, the proposed project site is bisected by a Western Area Power Administration Power line and is bordered on the south by the Contra Costa Canal – a US Bureau of Reclamation facility.  It is our understanding that the Contra Costa Water District is planning to encase the canal (an artificial tidal slough) due to the water quality impacts of adjacent land use changes including the project.  This will result in yet more destruction of wetlands associated with the canal.

Increase in risk for residents and levee failures
Most importantly, the project will place thousands of new and existing residents in harms way.  The project proposes placing approximately 4,000 homes and three public schools on land that lies five feet below sea level (see attached).  The new system of levees proposed is only designed to protect against a 300-year flood event.  Without proper maintenance the system will eventually fail under future storm and climate conditions.  The effects of sea level rise associated with climate change need to be taken into account because these changes will deeply flood entire neighborhoods.  Recent events with Hurricane Katrina suggest that cities have difficulty finding funds to maintain and update levees.  Thus, there is reason to believe that the City of Oakley will not maintain an adequate level of emergency preparedness to respond to such a catastrophe, especially since the current levee only protects against a 100-year flood event.   Additionally, maintaining the levees in the area will be more demanding because of the instability of the underlying soils the levee will be built on.

The catastrophe in New Orleans should prompt authorities to question the reliability of levees in protecting areas that are prone to flooding and to analyze the long-term effects of developing in a floodplain.  The system of levees in New Orleans was designed to protect against a 250-year flood event, which is only a 50-year difference from the proposed levee system in the East Cypress Corridor Project.  The US Army Corps of Engineers needs to conduct a NEPA review that takes into account the new information learned from Hurricane Katrina to make sure that the levee system will prevent another Hurricane Katrina disaster.  Additionally, there needs to be careful consideration over the potential for increased flooding as a result of both increasing the impervious surfaces on the site and construction of the alternative levee.

The NEPA review is also necessary to understand the risks associated with developing on the site considering that it may be underlain by a fault.  The EIR characterizes the site as being a few miles away from the Great Valley Fault.  The destructive Vacaville/Winters earthquake of 1898 (M 6.5) was attributed to the Great Valley Fault, a blind thrust fault.  Blind thrust faults are difficult to map definitively, particularly in areas with deep alluvial and estuarine sediments such as the project site.  The great valley fault is a fault zone, not a single fault.  Therefore, it is entirely possible that the project site is directly underlain by a branch of the Great Valley fault system.

The area proposed for development is in a seismically active zone subject to high liquefaction potential and traversed by major gas line and regionally important high voltage transmission lines.  The EIR does not adequately address any of these hazards, but completely ignores the combined or cumulative impact of failure of all of these systems (levees, gas lines, and power lines in the event of an earthquake).

Even more troubling, the new levee system will actually place existing residents with homes between the old and new levees at increased risk of deep flooding and reduced evacuation times.  The EIR for the proposed project acknowledges that assuming a breach of 170 feet, the inter-levee zone (area between new interior levee and existing levee) would flood to a water depth of up to ten feet (at waters surface elevation of 2 feet NGVD) within 4 hours. The same water depth would be realized after 16 hours under present conditions.  In reality, the analysis should assume a far larger levee breach size which would probably show that the inter levee zone could be inundated in a matter of minutes rather than hours.

Unknown cumulative impacts
The project raises numerous cumulative impact issues that can only be addressed through a thorough Environmental Impact Study.  The project is one of several currently proposed to urbanize low-lying lands around the Sacramento-San Joaquin Delta, but no entity has evaluated the combined water quality, ecosystem, water supply, and flood risk impacts of these projects.  The project is one of three or four major project currently proposed in the immediate vicinity that will significantly impact wetlands including the Contra Costa Canal encasement project, the Dutch Slough Tidal Marsh Restoration Project, the Delta Coves development project on Bethel Island, and the Dutch Slough development project immediately to the east on Cypress Road.  In addition, development projects planned and underway in Antioch, Pittsburg, and Concord could also have significant bearing on cumulative impacts, particularly Public Utilities (water supply) and transportation and circulation.  Thousand of acres of habitat and farmland combined with hundreds of acres of wetland will be converted by these projects, but the respective impacts are only analyzed in a piecemeal manner.

The US Army Corps of Engineers should address the cumulative impacts of the urban development around the perimeter of the delta on the state’s water supply system and the Delta ecosystem.  The Delta provides drinking water for 23 million people and is the most important aquatic ecosystem in the state of California.  Tens of thousands of new units are planned for construction around the Delta and the cumulative impacts that this development on the state’s water supply system should be analyzed.

Better alternatives
Alternative locations in the City Oakley should be seriously considered because it is the most authentic way for the Army Corps of Engineers to fulfill its mission to avoid and minimize impacts to aquatic resources.  New developments should be located near existing infrastructure before developing environmentally sensitive and prone to flooding area.  If the project were to move forward, the project should be reduced in size to lessen the environmental impacts and retain more of the site in open space capable of naturally addressing flooding.  Another option is to build denser development.

Greenbelt Alliance urges the US Army Corps of Engineers to conduct a full environmental impact study so that all residents, the environment, and wildlife will be protected from unnecessary and harmful development.  Greenbelt Alliance appreciates that the US Army Corps of Engineers extended the comment period, and requests that the US Army Corps of Engineers hold a public hearing on the matter so that all the stakeholders have an opportunity to provide information on the project.  Thank you for your consideration.


Christina S. Wong
East Bay Field Representative
Greenbelt Alliance

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