SUBJECT: The U.S. Army Corps of Engineers, Sacramento District, (Corps) is evaluating a permit application to construct the Phase II Frisco Bay Marina Facility Improvements project, which would result in impacts to approximately 16.3 acres of unvegetated lakebed in Dillon Reservoir, a water of the United States. This notice is to inform interested parties of the proposed activity and to solicit comments.
AUTHORITY: This application is being evaluated under Section 404 of the Clean Water Act for the discharge of dredged or fill material in waters of the United States.
APPLICANT: Town of Frisco, Point of Contact: Brodie Boilard, P.O. Box 4100, Frisco, Colorado 80443, Telephone: 970-668-9126
APPLICANT’S AGENT: Mr. Jason A. Deem, Gore Range Engineering, P.O. Box 24122, Silverthorne, Colorado 80497, Telephone: 970-485-4248
LOCATION: The 16.3-acre site is located at the Frisco Bay Marina, Dillon Reservoir, within Section 35, Township 5 South, Range 78 West, Sixth Principal Meridian, Latitude 39.57763°, Longitude
-106.0881°, Town of Frisco, Summit County, Colorado, and can be seen on the CO-FRISCO USGS Topographic Quadrangle and on the attached location map (Figure 1).
PROJECT NEED AND PURPOSE: The applicant’s stated purpose of the project is to expand and improve the recreational facilities of the Marina, including improving boater access during low water periods; providing a buffer to erratic water elevations in the Reservoir; increasing revenue-generating activities; increasing disabled user access; increasing dock space and reducing waiting periods; accommodating launching of larger boats; and increasing ability to stage events and programs at the Marina. Based on the available information, the Corps has determined that the basic project purposes are commercial development and navigation. The overall project purpose is to expand and develop recreational facilities and improve navigation at the Frisco Bay Marina.
PROJECT DESCRIPTION: The applicant is proposing to construct the Phase II Frisco Bay Marina facility expansion and improvements. The existing conditions at the marina are shown on Figure 2. The proposed marina expansion and improvements include constructing paved sidewalks and ADA accessible fishing piers; dredging to increase the water depth in the marina area; extending the boat ramp; installing a new boat hoist system, etc. The attached Figures 3 and 4 provide additional project details.
The proposed project would involve excavating approximately 75,400 cubic yards (CY) of soil from 10.93 acres of unvegetated lakebed, and discharging 60,300 CY of the dredged soil material and 3,600 CY / 1,720 linear feet of concrete retaining wall blocks into 5.35 acres of unvegetated lakebed below the ordinary high water mark of Dillon Reservoir. The discrepancy in dredged and fill soil volume is due to the void spaces that will be reduced after soil compaction. A total of 16.3 acres of unvegetated lakebed would be impacted, 5.3 acres of which would be permanently filled. Based on the preliminary wetland delineation and information provided by the applicant, the proposed project will not impact any wetlands, vegetated lake shore or vegetated lake bottom.
The applicant proposes to complete dredging /excavation when the Reservoir water levels are at an elevation below the proposed final excavation elevation of 9,001 feet to limit the need for dewatering and potential for siltation into the Reservoir. Typical construction equipment would be used, e.g., excavators, bulldozers, backhoes, dump trucks, etc.). Material dredged from the lakebed is expected to be composed of silt, sand, gravel and cobbles. Dredged material will be placed directly back onto the dry reservoir bottom.
The applicant’s proposed construction start date is April 1, 2013, depending on the water level and funding. The dredging and fill work would be completed first, and other proposed improvements would be completed in a phased approach. The applicant states that the project will be planned to avoid comingling of earthmoving operations with the water’s edge.
Background and Environmental Setting. Dillon Reservoir, owned and operated by Denver Water, was constructed in 1963 as a storage reservoir for the Denver Water system. The Town of Frisco leases the Frisco Bay Marina area from Denver Water. The reservoir collects water from the Blue River, Snake River, and Tenmile Creek, as well as many smaller streams. Dillon Reservoir covers approximately 3,233 acres and has a storage volume of approximately 267,304 acre feet. The spillway elevation that controls the maximum elevation of the reservoir is at 9,017 feet above mean sea level (MSL).
The Frisco Bay Marina complex lies at the southwest corner of Dillon Reservoir where Tenmile Creek and Miner’s Creek enter the reservoir. The Marina was originally developed in 1988 and consists of boat docks and ramp, a causeway in the old location of Highway 6, canoe and kayak storage, fueling station, a restaurant, office and store, playground and parking areas. Major improvements to the marina facilities (Phase I improvements) were completed in 2010-2011. The Phase I improvements included construction of approximately 380 feet of precast concrete lakeshore retaining wall, creation of a sand beach area, and improvements to the existing boat ramp, resulting in a permanent loss of 0.04 acre of open water and temporary impacts to 0.09 acre of open water. In addition to boating, Dillon Reservoir provides a variety of other recreational opportunities including fishing, hunting, camping, cycling and hiking in designated areas.
Alternatives. The applicant has provided information concerning project alternatives, summarized as follows:
Alternative 1 – Leave Marina As-Is: None of the planned improvements at the Marina facility would be completed.
Alternative 2 – Perform Dredging but Eliminate or Minimize Fill in Waters of the U.S.: Dredging operations would be conducted to allow for longer seasonal use of existing Marina facilities; fill would be limited to necessary bank stabilization, such as retaining walls. Applicant states that there is no suitable location on upland Marina property where the estimated volume of dredged material could be placed. Therefore, dredged soil would have to be transported to an off-site location, which would increase project costs and require approx. 5,000 dump truck trips through the Town of Frisco.
Alternative 3 – Reduce or Limit Dredge and Fill Areas: The applicant states that limiting the depth of dredge/excavation would negate overall dredging benefits because project objectives would not be met, including longer seasonal use of marina facilities, use of existing dock lengths, maximizing useable dock space area, accommodating the launch of larger vessels, and providing additional recreational opportunities such as ADA accessible fishing access.
Alternative 4 - Applicant Preferred: The applicant’s preferred alternative is described above, under PROJECT DESCRIPTION.
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, in particular those which may be less damaging to the aquatic environment, 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. The applicant states that the project, when fully constructed, will increase the existing shoreline from approx. 1,085 linear feet to 2,179 linear feet, and the net Reservoir storage volume will increase by 7.5 acre-feet. The applicant is not proposing any compensatory mitigation at this time.
OTHER GOVERNMENTAL AUTHORIZATIONS: Water quality certification or a waiver, as required under Section 401 of the Clean Water Act from the Colorado Department of Public Health and Environment (CDPHE), is required for this project. The applicant indicates that they have applied for water quality certification under Section 401 of the Clean Water Act with the CDPHE.
HISTORIC PROPERTIES: A cultural resources survey within the project’s area of potential effect will be required. The Corps will initiate consultation with the State Historic Preservation Officer under Section 106 of the National Historic Preservation Act, as appropriate.
ENDANGERED SPECIES: Based on the information provided, the project will not affect any Federally-listed threatened or endangered species or their critical habitat that are protected by the Endangered Species Act.
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-2010-00673 must be submitted to the office listed below on or before March 14, 2013.
Lesley McWhirter, Project Manager
US Army Corps of Engineers, Sacramento District
Colorado West Regulatory Branch
400 Rood Avenue, Room 224
Grand Junction, Colorado 81501
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 Lesley McWhirter, 970-243-1199, extension 17, Lesley.A.McWhirter@usace.army.mil.
1. Location Map
2. Existing Conditions drawing
3. Plan view drawing
4. Cross-section drawing