Comments Period: February 07, 2020 – March 06, 2020
SUBJECT: The U.S. Army Corps of Engineers, Sacramento District, (Corps) is evaluating a permit application to reconfigure and recondition existing boat docks within the Delta Coves project, which would result in structures or work in approximately 6.35 acres of Sand Mound Slough. This notice is to inform interested parties of the proposed activity and to solicit comments.
AUTHORITY: This application is being evaluated under Section 10 of the Rivers and Harbors Act of 1899 for structures or work in or affecting navigable waters of the United States.
APPLICANT: DMB Associates, Mr. Nick Taratsas, 7600 East Doubletree Ranch Road, Suite 300, Scottdale, Arizona 85258-2137
LOCATION: The approximately 6.35-acre project site is located within an existing man-made lagoon that was constructed as portion of the Delta Coves Residential Development (DCRD) at the southern portion of Bethel Island in Contra Costa County, in Latitude 38.04483°, Longitude -121.50993°, San Joaquin County, California., and can be seen on the Bouldin Island USGS Topographic Quadrangle.
PROJECT DESCRIPTION: The applicant is proposing to reconfigure of boat docks and recondition existing docks and to add multiple boat slips at the base of the docks. Based on the available information, the overall project purpose is to provide boat access and maintenance of the boat dock. The proposed project consists of the following components as described below:
The DCRD was constructed under Regulatory Permit No. 199400393 in 2006 as depicted on the attached Exhibit 3. The DCRD included excavation of a man-made lagoon, which is indirectly connected to the Sacramento-San Joaquin Delta through a series of channels. Prior to construction of the DCRD, the site was agricultural land. The lagoon is lined by a reinforced levee that abuts Bethel Island. The interior of the lagoon is approximately 4-5 meters (m) deep. The levee of the lagoon is largely devoid of vegetation. Subtidal waters less than 2m deep are largely colonized by dense beds of Egeria densa, a type of invasive submerged aquatic vegetation.
Grading of the DCRD began in 2006 and was completed in 2008; however, due to the economic downturn, construction of residences and commercial/recreational structures was significantly delayed until present. At this time, the lagoon and levee have been constructed, along with 494 single family residential graded lots, multi-family residential graded lots, commercial/recreational areas, and internal roadways. Of the 494 residential lots, 416 individual docks have been installed (see attached Exhibit 3). Currently, 78 residential lots do not contain individual homeowner docks, as these lots are located on the inside “elbows” of the site and the configuration of T-shaped docks cannot be accommodated due to space constraints. Over the past eight years, the docks have experienced wear and tear, along with vandalism. The galvanized anchor chains associated with many of the docks have broken or are deteriorated, resulting in docks that are floating within the lagoon or have washed onto land.
Current Proposed Project
The proposed project activities, as depicted on attached Exhibit 4, would use both land-based equipment, where feasible, and equipment that would mount on a barge within the lagoon, where necessary. Approximately 300 of the existing docks would have their anchors replaced with a newer four-cable anchor system developed by Sea Flex. This new system would use the existing lagoon floor anchorage and replace the cable system between the anchorage and the dock. The remaining docks within corner areas of the lagoon or at the point lots at the end of the cul-de-sacs, due to the geometry of these docks, would be secured to the lagoon floor with 10-inch steel tube piles. These piles have a lifespan of 100+ years and are not deleterious for use in aquatic environments. Using piles reduces the risk of future docks becoming untied, floating away, and damaging other docks.
Repair/Demolition of Existing Docks
All 416 existing individual docks would be examined, cleaned, and repaired in place. Those in extremely poor condition would be removed from the lagoon. All spoils would be removed from water to land and transported to a legal dumpsite; materials that can be reused or repurposed, such as metal gangways, would be stored on land. Where existing gangways are in the same location as the proposed multi-slip docks (described below), they would be left in place. This Project component would occur over the life of the permit and would take place as portions of the residential development go under contract with homebuilders.
Construction of Multi-Slip Docks
The project would provide each homeowner with private access to either one or two slips, as shown on Exhibit 4. Whereas the existing dock configurations are t-shaped, the proposed docks would have fingers that extend perpendicularly from the dock in order to create multiple slips at each dock. The docks would be set into the water with a crane and bolted together. The maximum distance that docks would extend into the lagoon is 48 feet.
To secure the docks, new 10-inch hollow core steel pilings would then be driven into the lagoon with a vibratory hammer, onto which the docks would be bolted. The total number of piles for all multi-slip docks is 180: two for each 2-slip dock, three for each 3-slip dock, and four for each 4-slip dock. Each pile is 10 inches in diameter and approximately 30-40 feet in length. Addition of the multi-slip docks would add 6.35 acres of surface area coverage over the lagoon.
Addition of Shade Canopies and Center-Mount Boat Lifts
Up to two shade canopies may be added to each dock. The canopies would be removable and may extend up to 15 feet over the water, beyond the dock. All attachment parts for the canopy would be located on the dock.
A maximum of two center-mount boat lifts per dock would be attached to internal sides of the fingers/dock. This would allow for dry-storage of boating vessels and is a necessary feature required by homeowners in this market.
Neither the shade canopies nor the boat lifts would result in surface area coverage as they would be above water permanently, or in the case of the boat lifts, only be lowered into the water while the vessel is going into or coming out of the water.
The applicant believes the need for the following:
1. To provide each property owner with a functional dock and improvements to the deterioration of existing dock anchorages, and to upgrade the docks to provide multi-slip capacity.
2. The existing T-shaped docks are not designed for use by a permanent resident. They are designed for use by visitors who docks their boat elsewhere. Homebuyers need a means to lift their boat out of the water for dry storage. The multi-slip configuration allows this to happen, and it is a basic simple operation where the boat is lifted between the slips. It also provides each homeowner with the use of at least one dock and slip, which currently not all lots offer due to the elbow configuration of the corner lots. The attached drawings provide additional project details.
Environmental Setting. There are approximately 6.35 acres of open waters within the project area. The site is characterized as an existing man-made lagoon and described with access to Sand Mound Slough via eastern portion of the project site.
Alternatives. The applicant has not provided information concerning project alternatives for NEPA under the Section 10 of the Rivers and Harbors Act of 1899 for structures or work in or affecting navigable waters of the United States. Additional information concerning project alternatives may be available from the applicant or their agent. Other alternatives may develop during the review process for this permit application. All reasonable project alternatives will be considered.
Mitigation. The Corps requires that applicants consider and use all reasonable and practical measures to avoid and minimize impacts to aquatic resources. If the applicant is unable to avoid or minimize all impacts, the Corps may require compensatory mitigation.
OTHER GOVERNMENTAL AUTHORIZATIONS: Water quality certification or a waiver, as required under Section 401 of the Clean Water Act from the Central Valley Water Quality Control Board is not required for this project. The applicant has indicated they have applied for certification.
HISTORIC PROPERTIES: Based on the available information and under the previous authorization for the DCRD, the Section 106 of the National Historic Preservation Act of 1966, as amended (NHPA) had addressed impacts to cultural resources listed on, or eligible for listing on the National Register of Historic Places. Work activities would be working from previous permitted surfaces.
ENDANGERED SPECIES: The project would not affect any Federally-listed threatened or endangered species or their critical habitat that are protected by the Endangered Species Act. The Corps will initiate consultation with the U.S. Fish and Wildlife Service and the National Marine Fisheries Service, pursuant to Section 7 of the Endangered Species Act, as appropriate.
ESSENTIAL FISH HABITAT: The proposed project would not adversely affect Essential Fish Habitat (EFH) as defined in the Magnuson-Stevens Fishery Conservation and Management Act. The Corps will initiate consultation with the National Marine Fisheries Service, pursuant to Magnuson-Stevens Fishery Conservation and Management Act, as appropriate.
The above determinations are based on information provided by the applicant and our preliminary review.
EVALUATION FACTORS: The decision whether to issue a permit will be based on an evaluation of the probable impacts, including cumulative impacts, of the described activity on the public interest. That decision will reflect the national concern for both protection and utilization of important resources. The benefit, which reasonably may be expected to accrue from the described activity, must be balanced against its reasonably foreseeable detriments. All factors which may be relevant to the described activity will be considered, including the cumulative effects thereof; among those are conservation, economics, aesthetics, general environmental concerns, wetlands, historic properties, fish and wildlife values, flood hazards, floodplain values, land use, navigation, shoreline erosion and accretion, recreation, water supply and conservation, water quality, energy needs, safety, food and fiber production, mineral needs, consideration of property ownership and, in general, the needs and welfare of the people. The activity's impact on the public interest will include application of the Section 404(b)(1) guidelines promulgated by the Administrator, Environmental Protection Agency (40 CFR Part 230).
The Corps is soliciting comments from the public, Federal, State, and local agencies and officials, Indian tribes, and other interested parties in order to consider and evaluate the impacts of this proposed activity. Any comments received will be considered by the Corps to determine whether to issue, modify, condition, or deny a permit for this proposal. To make this decision, comments are used to assess impacts on endangered species, historic properties, water quality, general environmental effects, and other public interest factors listed above. Comments are used in the preparation of an Environmental Assessment and/or an Environmental Impact Statement pursuant to the National Environmental Policy Act. Comments are also used to determine the need for a public hearing and to determine the overall public interest of the proposed activity.
SUBMITTING COMMENTS: Written comments, referencing Public Notice SPK-1994-00393 must be submitted to the office listed below on or before March 06, 2020.
Peck-Leong Ha, Senior Project Manager
US Army Corps of Engineers, Sacramento District
The Corps is particularly interested in receiving comments related to the proposal's probable impacts on the affected aquatic environment and the secondary and cumulative effects. Anyone may request, in writing, that a public hearing be held to consider this application. Requests shall specifically state, with particularity, the reason(s) for holding a public hearing. If the Corps determines that the information received in response to this notice is inadequate for thorough evaluation, a public hearing may be warranted. If a public hearing is warranted, interested parties will be notified of the time, date, and location. Please note that all comment letters received are subject to release to the public through the Freedom of Information Act. If you have questions or need additional information please contact the applicant or the Corps' project manager Peck-Leong Ha, (916) 557-6617, Peck.Ha@usace.army.mil.
Attachments: 5 drawings