Great Chebeague Island Chebeague Island, Maine

Transcription

1 Initial Appraisal of Federal Interest For Continuing Authority Feasibility Investigation Section 107 Navigation Improvement Study Great Chebeague Island Chebeague Island, Maine US ARMY CORPS OF ENGINEERS New England District July 2014

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3 NAVIGATION IMPROVEMENT STUDY INITIAL APPRAISAL OF FEDERAL INTEREST GREAT CHEBEAGUE ISLAND MAINE July 2014

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5 Great Chebeague Island, Maine Initial Appraisal of Federal Interest July Project Name: Great Chebeague Island Navigation Improvement Project, Chebeague Island, Maine. Study Authorized under the Continuing Authority of Section 107 of the River and Harbor Act of 1960, as amended. 2. Congressional District: Maine 1st (Representative Pingree) Senators: Collins and King (ME) 3. Project Purpose and Description This study investigated whether Federal participation in a feasibility study to consider providing navigation improvements for Great Chebeague Island, in partnership with the Town of Chebeague Island, are warranted. The Town of Chebeague Island is a municipality consisting of 17 islands in upper Casco Bay, Cumberland County, Maine, about 10 miles north of Portland. Two of the Town s islands are inhabited, of which Great Chebeague Island is the largest. The Town is isolated, with no bridge access to the mainland. Figure 1 shows the island and its location in the bay. The municipally chartered Chebeague Transportation Company (CTC) provides year-round barge and ferry service for passengers and light cargo from nearby Cumberland. The principal Town landing is at the Stone Wharf on the northwest shore of the island. Other private services operate seasonally from Portland. Vehicles, fuel, trash, seafood, utility service, and building materials are carried by barge. About 340 people live year-round on the island with another approximately 1,700 summer residents. The principal commercial activity is fishing with about 44 vessels licensed primarily for lobstering, and another 19 vessels used for freight and passenger transportation. Town officials report that shallow water hinders operation of the many activities that rely on the landing at the Stone Pier, including fishing, barge and ferry operations. As the Island s principal landing, public safety, the island economy, and island services all depend on adequate access to the mainland over the pier. While depth alongside the pier on the mainland (Cousins Island) end are naturally deep, shallow water at the Stone Pier on Great Chebeague Island limits access to higher stages of the tide and causes damage to craft using the pier. Deepening of the channel to the pier, with adequate maneuvering/turning areas for vessels, and adequate anchorage for the commercial fishing fleet are necessary to ensure safe navigation access. 4. Prior Studies and Improvements There is no existing Federal Navigation Project for Great Chebeague Island. This site was the subject of studies conducted under Section 107 in the early 1970s, a time when the islands now comprising the Town of Chebeague Island were part of the mainland Town of Cumberland. Chebeague Island formed its own Town in

6 CUMBERLAND Great Chebeague Island Landing Stone Pier Cousins Island Landing FALMOUTH GREAT CHEBEAGUE ISLAND casco LONG ISLAND PORTLAND PORTLAND HARBOR PEAKS ISLAND BAY FIGURE 1 GREAT CHEBEAGUE ISLAND, MAINE -2- NAVIGATION IMPROVEMENT STUDY PROJECT LOCATION

7 A Reconnaissance Report dated 25 February 1971, and a Detailed Project Report dated 5 June 1973 examined navigation access improvements for Great Chebeague Island. The DPR recommended a channel from deep water to the pier and anchorage areas for the local fishing and seasonal recreational fleet on either side of the channel totaling 14 acres, all dredged to -6 feet at mean low water. The Town of Cumberland declined to provide the required cost-sharing for construction. The plan of improvement from 1973 is shown in Figure Existing Navigation Conditions, Problems and Opportunities Great Chebeague Island relies on vessel access through the Stone Pier for all of its needs and services. The principal route to the mainland is over the Stone Wharf to the mainland wharf at Cousins Island in Cumberland. Cousins Island is connected to the mainland by a bridge. The trip between the wharves is approximately 15 minutes, depending on the tide. Fishermen ship their catch over the pier. Emergency services (police, fire), commuters including school children and teachers, utility service, food, fuel, building supplies, road paving, trash, etc., all come over the island s landings. The ferries carried about 125,000 passengers in Controlling depth in the pier approach is currently less than 5 feet. The Town has conducted minor dredging in the past to keep ferry access at least in higher tidal stages. Navigational improvements are needed to ensure the island maintains its critical public navigational access. The Harbor Master reports several problems with the existing channel conditions. Deep draft lobster vessels have run aground in the pier approaches when bringing in catch. These vessels must also tie up to a floating dock in order to load supplies or off load catch because the area along the Stone Wharf is too shallow. Approximately 200 feet inshore of the ferry berth is a boat/barge ramp located at the end of Stone Wharf Road. The ramp can only be used at high tide because that area is exposed during low tides. Tides in Casco Bay are semi-diurnal with significant variance in range. The mean tidal range at Great Chebeague Island is 9.1 feet, with minimum and maximum ranges about 3.5 feet less or greater. Barging between Great Chebeague Island and the dock at Cousins Island, or Portland Harbor, is also severely restricted by the tide at the Chebeague Island end of the routes. The ferries now have less than 1 foot underkeel clearance at low tide when tying up to the wharf, and are restricted from approaching the wharf on minus tides or in seas exceeding that clearance as they would ground in the shallow water, potentially causing damage to the vessel or cargo and injury to passengers. Most importantly, lack of adequate depth may restrict rescue services in an emergency situation. As stated earlier, the commercial fishing fleet consists of 44 commercial vessels registered on Great Chebeague Island. The CTC provides two ferries that provide passenger and small freight ferry service from Cousins Island times throughout the day; seven days per week, tides and weather permitting. A barge and push boat transport vehicles and commercial freight from April 1st to November 30th each year. Other private barge and freight operations also service the Island. The CTC transports school students and emergency/rescue services. CTC personnel respond for emergency transport at any time day or night to connect Island police and ambulance service with the mainland. -3-

8 -4- FIGURE PROPOSED PROJECT 6-Foot Channel 6-Foot Anchorages

9 Providing adequate depth in the approaches to the Stone Wharf, its berths and barge ramp, and adequate anchorage for it fishing fleet, are critical to the island s economy and the safety of its residents. A list of the Island fleet with vessel dimensions is provided in Table 1, drawn from 2012 fleet data provided by the Chebeague Island Harbormaster. TABLE 1 GREAT CHEBEAGUE ISLAND, MAINE NAVIGATION IMPROVEMENT PROJECT - FLEET SUMMARY Commercial Fishing Boats Vessel Types and Dimensions (Feet) Draft Range # of Vessels Average Length Average Beam Smaller Draft Fishing Vessels < Middle-Range Draft Fishing Vessels 4.5 to Larger-Draft Fishing Vessels > Commercial Ferries and Cargo Transports Vessel Types and Dimensions (Feet) Draft # of Length Beam Range Vessels Range Range Chebeague Transportation Company Ferries 6.5 to Freight Barges 4.0 to Fuel Barge Casco Bay Lines Ferries Inter-Island Ferries Barge Push Boats Municipal Craft Draft # of Average Average Vessel Types and Dimensions (Feet) Range Vessels Length Beam 4.0 to Harbormaster and Water Taxi Commercial - Utility Service and Other Non-Fishing Boats Vessel Types and Dimensions (Feet) Draft # of Average Average Range Vessels Length Beam Utility Service Vessels 3.0 to to Boat Yard Service Charter Vessel

10 6. Plan Formulation and Design This study involved preliminary design needs, cost and benefit analyses of providing improvements to navigation access for Great Chebeague Island. A channel to access the berths at the Stone Pier, with maneuvering area alongside the pier and barge ramp, and adjoining anchorage for the needs of the commercial fleet were designed based on a new hydrographic survey of that site. Costs were estimated using a variety of information sources, including hydrographic data, sediment information obtained from the Town s prior investigations, subsurface probes made during the study, aerial photos, site visits, and interviews with harbor users and people knowledgeable about the site and the Island. Vessel drafts and safe underkeel clearances appropriate for the types and sizes of vessels using the Stone Pier were computed and used to evaluate channel design depths with respect to tidal conditions. Channel width assumed two-way traffic with fishing boats passing a barge or ferry. Maneuvering area width assumed the turning of the largest ferry and barge in the CTC fleet. Anchorage areas were designed in two depth increments, one for the smaller class of fishing boats in the fleet and the other for the larger fishing boats and transportation/ service vessels. While the waters of upper Casco Bay are largely protected by the Bay s many islands from ocean waves and swells, the waters along the west side of Great Chebeague Island are exposed to winds from the northeast and southwest. The Cove in which the Stone Pier landing is located is a shallow open water body with areas inshore of a line between the two headlands northeast and southwest of the cove slightly more protected. To ensure safe access throughout the year for moored fishing and other vessels based in this area any developed anchorage should be located inshore of a line between the two headlands. No recreational anchorage has been included due to the low priority assigned such uses. It is assumed that recreational boats would moor seaward of the more protected inshore commercial anchorages during the calmer summer recreational season. The project layout used for this analysis is shown in Figure 3. Chebeague is a relatively newly organized municipality with limited resources. To meet the Town s needs for choices in moving forward with navigation improvements two plans were developed. One plan would focus solely on ensuring safe and efficient access to the landing at the Stone Pier for ferries and cargo carriers, and vital services for the island. The other would expand on that base plan to provide improved year-round access for the Town s commercial fishing fleet as well. The two plans evaluated for this appraisal consist of the following project features: Plan A: A channel 100 feet wide and -10 feet MLLW from deep water in Casco Bay southeasterly to Great Chebeague Island public landing at the Stone Pier, widened to 150 feet alongside the pier for maneuvering and turning of vessels, an upper maneuvering/turning basin at -8 feet MLLW between the channel and the boat/barge ramp area by about 150 to 100 feet wide; Plan B: In addition to the features provided in Plan A, Plan B would provide a -8-foot MLLW by 13-acre anchorage area located northeast of the proposed channel, and a -6- foot MLLW by 13-acre anchorage located southwest of the proposed channel. -6-

11 N US Army Corps of Engineers New England DATE APPR. District APPR. M ARK DESCRI PTI ON D DATE N DESCRI PTI ON F C T I W D E C N N A H I W M ARK L E T H T B CHB_C101. dgn FI LE NAM E: 09/ 17/ 2012 CKD BY: DRAW I NG CODE: XXXXXXXXX ANSID north of the NE corner of a shed, the only building on SI ZE: 45 ft east of the NE concrete leg of the pier, and 37.5 ft 1" =200' MM/ 20YY of a 50 ft tall oak tree, the only tree on Indian Point, DW N BY: set flush in a rock outcropping, east of the pier 146 ft. NW PLOT SCALE: PLOT DATE: DATE: A Bob M eader E DESI GNED BY: R 3. Bench Mark Data: BM Squaw (2012) is the primary bench mark CONXXBXXXX A noted and should be used as a general reference only. CONTRACT NO. : G bridges, piers, etc., is located approximate unless otherwise Bob A.Subm i t t er N NOAA Chart No All topography, including shoreline, W 912W JXXXXXXX I 2. Topography shown is from 2011 aerial photography and/or SUBM I TTED BY: SOLI CI TATI ON NO. : N plane of Mean Lower Low Water (MLLW) Tidal Epoch. CKB R Soundings are in feet and tenths and refer to the Bob M eader U GENERAL NOTES: 5. Survey was performed using an Odom MK2 echotrac 100-FT WIDE echosounder. Horizontal positioning was obtained utilizing a UPPER TURNING BASIN Leica 1200 GPS System. An RTK base station was set up on BM Squaw. (2012) 5. The sounding information shown on this map represents the SHOALEST soundings of those obtained from hydrographic surveys conducted during July The sounding information depicted on this map should CONCORD,M ASSACHUSETTS Grid System for the State of Maine (West Zone 1802) & NAD CORPS OF ENGI NEERS 4. Coordinates shown are based on the Transverse Mercator U.S.ARM Y ENGI NEER DI STRI CT Indian Point. Elevation is feet above MLLW. Survey by: Paul K. O'Brien and crew Refer to Survey No Rep A GRAPHIC SCALE: 200 E E E " = 200' FOOT TURNI NG BASI N 8. Field Book: R&H FOOT CHANNEL AND considered as indicating the general conditions existing at that time. CHEBEAGUE HARBOR results of surveys made on the dates indicated, and can only be PLAN A 7. The information depicted on this map represents the GREAT CHEBEAGUE I SLAND,M AI NE information is available upon request. PROJECT TI TLE 4 from more sounding information than shown. Additional sounding N NAVI GATI ON I M PROVEM ENT FEASI BI LI TY STUDY NOT be used to determine volumes. Volumes are determined SHEET IDENTIFICATION G-001 SHEET 1 OF 1

12 N US Army Corps of Engineers New England DATE APPR. District APPR. M ARK DESCRI PTI ON D DATE N DESCRI PTI ON NORTHEAST ANCHORAGE F C T I W D E C N N A H I W M ARK L E T H T DRAW I NG CODE: XXXXXXXXX 09/ 17/ 2012 CHB_C101. dgn B FI LE NAM E: north of the NE corner of a shed, the only building on ANSID 45 ft east of the NE concrete leg of the pier, and 37.5 ft SI ZE: of a 50 ft tall oak tree, the only tree on Indian Point, 1" =200' MM/ 20YY CKD BY: set flush in a rock outcropping, east of the pier 146 ft. NW DW N BY: 3. Bench Mark Data: BM Squaw (2012) is the primary bench mark PLOT SCALE: PLOT DATE: DATE: A Bob M eader E DESI GNED BY: R noted and should be used as a general reference only. CONXXBXXXX A bridges, piers, etc., is located approximate unless otherwise CONTRACT NO. : G NOAA Chart No All topography, including shoreline, Bob A.Subm i t t er N 2. Topography shown is from 2011 aerial photography and/or W 912W JXXXXXXX I plane of Mean Lower Low Water (MLLW) Tidal Epoch. SUBM I TTED BY: SOLI CI TATI ON NO. : N 1. Soundings are in feet and tenths and refer to the CKB R -8SOUTHWEST ANCHORAGE Bob M eader U GENERAL NOTES: 5. Survey was performed using an Odom MK2 echotrac 100-FT WIDE echosounder. Horizontal positioning was obtained utilizing a UPPER TURNING BASIN Leica 1200 GPS System. An RTK base station was set up on BM Squaw. (2012) 5. The sounding information shown on this map represents the SHOALEST soundings of those obtained from hydrographic surveys conducted during July The sounding information depicted on this map should CONCORD,M ASSACHUSETTS Grid System for the State of Maine (West Zone 1802) & NAD CORPS OF ENGI NEERS 4. Coordinates shown are based on the Transverse Mercator U.S.ARM Y ENGI NEER DI STRI CT Indian Point. Elevation is feet above MLLW. considered as indicating the general conditions existing at that time. 8. Field Book: R&H 3127 Survey by: Paul K. O'Brien and crew Refer to Survey No Rep A GRAPHIC SCALE: 200 E E E " = 200' CHEBEAGUE HARBOR results of surveys made on the dates indicated, and can only be PLAN B 10FOOT CHANNEL AND 80FOOT TURNI NG BASI NWI TH 6FOOT AND 8FOOT ANCHORAGE AREAS 7. The information depicted on this map represents the GREAT CHEBEAGUE I SLAND,M AI NE information is available upon request. PROJECT TI TLE 4 from more sounding information than shown. Additional sounding N NAVI GATI ON I M PROVEM ENT FEASI BI LI TY STUDY NOT be used to determine volumes. Volumes are determined SHEET IDENTIFICATION G-001 SHEET 1 OF 1

13 Based on the subsurface probes conducted during the prior study, no ledge is expected to be encountered in the area to be dredged. Dredged material is anticipated to be a mix of silts, clays and sand. Dredged material quantities are shown in Table 2 and are based on a hydrographic survey conducted in July The material from the Town s last shoal removal in the Pier approach was found suitable for placement at the Portland Disposal Site, located seaward of the territorial sea off Cape Elizabeth at the mouth of the Bay. For the purpose of this study it was assumed that the material would be suitable for placement at the Royal River (Historic Broad Sound) site in upper Casco Bay about 6 miles from the project site. That site is shown in Figure 4. Alternatively the historic Luckse Sound and Cape Elizabeth (Ram Island) sites located further seaward are also landward of the territorial sea baseline in primarily state-regulated waters of the outer bay. The Portland Disposal Site is located even further seaward beyond the territorial sea and has been designated for dredged material placement by the EPA. 7. Project Costs For this type of mixed material and area of the coast dredging equipment would include a barge-mounted mechanical bucket dredge, scows to transport the dredged material to a nearby open-water disposal site, and one or more tugs to tow the scows and position the dredge barge, with attendant work boats to move equipment and crew, and survey boats to track progress. The plant would be of a size able to operate in shallow draft areas around the Stone Pier, with the dredge likely digging its way in from deep water southeast towards the inshore limit of the dredge area. For the purposes of this estimate for both Plans A and B an 8 cubic yard (CY) dredge bucket or excavator was assumed along with two 1,500 CY bottom dump split hull scows and one tug. Details for the cost of dredging are provided in Attachment B. A reconnaissance-level cost estimate for the channel was prepared. A summary of first costs at the 2014 price level is shown on Tables 3A and 3B. -9-

14 TABLE 2 - GREAT CHEBEAGUE ISLAND, MAINE NAVIGATION IMPROVEMENT PROJECT - QUANTITY ESTIMATES -10- Project Features From 2012 Report Survey Channel to Stone Wharf 100-Foot Wide Channel with 150 x 300-Foot Maneuvering/Turning Area 6-Foot Channel and Turning Area 7-Foot Channel and Turning Area 8-Foot Channel and Turning Area 9-Foot Channel and Turning Area 10-Foot Channel and Turning Area Turning Basin at Stone Wharf Barge Ramp 100-Foot Wide Upper Turning Basin 6-Foot Turning Basin 7-Foot Turning Basin 8-Foot Turning Basin 9-Foot Turning Basin 10-Foot Turning Basin Anchorage Areas East and West of Channel Northeast Anchorage Area - 13 Acres 6-Foot Anchorage 7-Foot Anchorage 8-Foot Anchorage 9-Foot Anchorage Southwest Anchorage Area - 13 Acres 6-Foot Anchorage 7-Foot Anchorage 8-Foot Anchorage 9-Foot Anchorage Quantity - Ordinary Material - CY Cut to Required Depth NOTE: All quantities and areas include 1 on 3 side slopes 1-Foot Allowable Overdepth Total Cubic Yards 3,800 2,000 5,800 5,800 2,700 8,500 8,500 3,500 12,000 12,000 4,000 16,000 16,000 4,800 20,800 7,500 1,400 8,900 8,900 1,500 10,400 10,400 1,600 12,000 12,000 1,700 13,700 13,700 1,700 15,400 2,300 4,100 6,400 6,400 6,900 13,300 13,300 10,500 23,800 23,800 13,700 37,500 34,700 18,400 53,100 53,100 23,500 76,600 76,600 28, , ,100 32, ,200 Area for Required Depth Dredged Area (SF) 1-Foot Allowable Overdepth Total Area (SF) Total Area (Acres) 49,410 17,280 66, ,690 19,030 85, ,720 15, , ,540 22, , ,820 13, , ,700 2,000 39, ,700 1,970 41, ,670 2,040 43, ,710 2,090 45, ,800 2,140 47, ,810 68, , ,310 88, , ,570 89, , ,000 71, , , , , , , , , , , ,020 73, ,

15 FIGURE 4 ALTERNATIVE DISPOSAL SITES IN CASCO BAY Project Site Historic Broad Sound Site Outer Broad Sound Site Historic Luckse Sound Site Historic Cape Elizabeth Site Territorial Sea Baseline To Portland 103 Ocean Disposal Site From NOAA Chart #13290 Casco Bay -11-

16 TABLE 3A GREAT CHEBEAGUE ISLAND, MAINE - NAVIGATION IMPROVEMENT PROJECT IMPROVEMENT DREDGING - PROJECT COSTS - PLAN A Quantities from 2012 Study Survey Cost Price Level = 1st Quarter FY14 Quantity Unit Cost Total Project Cost Mobilization/Demobilization LS $238,000 $238,000 Improvement Dredging and Disposal Ordinary Material - Improvement Dredging of 10-Foot Channel Distribution Percentage 20, % Required - 1st 16,000 CY 16,000 $8.34 $133,000 Allowable - Over 16,000 CY 4,800 $8.34 $40,000 Ordinary Material - Improvement Dredging of 8-Foot Turning Basin 12, % Required - 1st 10,400 CY 10,400 $8.34 $87,000 Allowable - Over 10,400 CY 1,600 $8.34 $13,000 Debris and Boulder Removal First 20 Tons 20 $ $5,000 Over 20 Tons 20 $ $5,000 TOTAL CONTRACT COST 32,800 $15.88 $521, % Contingency 22% $115,000 Engineering and Design $114,000 Supervision and Administration $149,000 TOTAL FIRST COST $27.41 $899,000 Construction Duration with M/DM 2 Months Interest During Construction $1,000 Total Investment $900,

17 TABLE 3B GREAT CHEBEAGUE ISLAND, MAINENAVIGATION IMPROVEMENT PROJECT IMPROVEMENT DREDGING - PROJECT COSTS - PLAN B Quantities from 2012 Study Survey Cost Price Level = 1st Quarter FY14 Quantity Unit Cost Total Project Cost Distribution Percentage Mobilization/Demobilization LS $238,000 $238,000 Improvement Dredging and Disposal Ordinary Material - Improvement Dredging of 10-Foot Channel 20, % Required - 1st 16,000 CY 16,000 $8.34 $133,000 Allowable - Over 16,000 CY 4,800 $8.34 $40,000 Ordinary Material - Improvement Dredging of 8-Foot Turning Basin 12, % Required - 1st 10,400 CY 10,400 $8.34 $87,000 Allowable - Over 10,400 CY 1,600 $8.34 $13,000 Ordinary Material - Improvement of 8-Foot Northeast Anchorage 23, % Required - 1st 6,300 CY 13,300 $17.41 $232,000 Allowable - Over 6,300 CY 10,500 $17.41 $183,000 Ordinary Material - Improvement of 6-Foot Southwest Anchorage 53, % Required - 1st 21,100 CY 34,700 $17.41 $604,000 Allowable - Over 21,100 CY 18,400 $17.41 $320,000 Debris and Boulder Removal First 100 Tons 100 $ $25,000 Over 100 Tons 100 $ $25,000 TOTAL CONTRACT COST 109,700 $17.32 $1,900, % Contingency 20% $380,000 Engineering and Design $184,000 Supervision and Administration $266,000 TOTAL FIRST COST $24.89 $2,730,000 Construction Duration with M/DM 3 Months Interest During Construction $8,000 Total Investment $2,738,

18 In order to compare project costs and benefits both must be stated in annual terms. Project first costs for both plans are amortized using the current Federal fiscal year interest rate for water resources development of 3-1/2% over the 50-year project life used for navigation projects. Future costs of project operation and maintenance must also be computed and annualized. For the purpose of this initial appraisal conservative annual shoaling rates equal to 5 percent (in the anchorages) to 8 percent (in the channel and basin) of the improvement quantity were used together with the current estimate s total first cost unit cost. The Great Chebeague Island harbor is significantly protected in its upper reaches and therefore unlikely to require frequent maintenance. In addition, the harbor lacks any substantive sediment sources. The Annual Costs for the Great Chebeague Island navigation improvement project at the 2014 price level is shown in Table 4. TABLE 4 GREAT CHEBEAGUE ISLAND, MAINE NAVIGATION IMPROVEMENT PROJECT ANNUAL COSTS PLAN A Channel and Basin Only PLAN B Channel, Basin and Anchorages First Cost of Construction $899,000 $2,730,000 Construction Duration (Months) 2 3 Investment Cost (Includes IDC) $900,000 $2,738,000 Interest and Amortization (3-1/2% -50 Years) $38,400 $116,700 Annualized Maintenance Dredging $71,900 $136,500 Total Annual Cost $110,300 $253, Project Benefits Project benefits for Plans A and B are expressed in annual terms and include gains in efficiency experienced by the commercial transportation operations and the fishing fleet due to dredging and maintaining adequate all-tide access to Great Chebeague Island over the Stone Pier landing site. Benefits for both projects are derive from reduced tidal delays and grounding damages avoided. Elimination of tidal delays will result in reduced labor and reduced vessel fuel costs incurred while waiting to offload passengers, fish catch and freight at the Stone Wharf. Reduced grounding damages resulting in lower vessel maintenance, inspection and repair costs and reduced vessel down-time. The proposed project would benefit the commercial fleet by reducing the cost of these operating inefficiencies and providing a safer area in which to maneuver for access to loading and off-loading facilities at the Stone Wharf. The complete assessment of economic benefits to commercial navigation at Great Chebeague Island can be found in Attachment C. The Annual Benefits for the Great Chebeague Island navigation improvement project at the 2014 price level are shown in Table 5 below. -14-

19 TABLE 5 GREAT CHEBEAGUE ISLAND, MAINE NAVIGATION IMPROVEMENT PROJECT - ANNUAL BENEFITS PLAN A Channel and Basin Only PLAN B Channel, Basin and Anchorages Fishing Vessels: Additional Labor Costs due to Tidal Delays $306,000 Non-Fishing Vessels: Additional Labor Costs due to Tidal Delays $470,000 $470,000 Fishing Vessels: Additional Fuel Costs due to Tidal Delays $213,400 Non-Fishing Vessels: Additional Fuel Costs due to Tidal Delays $229,900 $229,900 Commercial Fleet Grounding Damages Avoided $37,000 $37,000 Total Annual Benefits $736,900 $1,256, Environmental Considerations The project is not expected to entail any significant environmental concerns. Most impacts to ecological resources such as water quality, sediment quality, and biological resource impacts are expected to be short-term and localized. The improvement dredging and disposal activities would temporarily impact essential fish habitat in the project area to a minimal degree. Endangered species and historic properties are not anticipated to be significantly impacted. The feasibility study will need to inventory the ecological conditions (sediment chemistry, SAV and other biological resources, etc.) and cultural resource conditions of the project area, and an Environmental Assessment will need to be prepared. 10. Recommendations Benefit/Cost analysis (see Table 6 below) indicates a positive Benefit to Cost Ratio (BCR) for both Plans A and B. The preliminary plan of improvement for the purpose of commercial navigation consisting of channel, turning/maneuvering basin (Plan A), and channel, turning/maneuvering basin, and anchorage improvements (Plan B) for Great Chebeague Island. These improvements were found to have a net annual benefit of $626,600 and a BCR of 6.68 for Plan A, and $1,003,100 and a BCR of 4.96 for Plan B. -15-

20 TABLE 6 GREAT CHEBEAGUE ISLAND, MAINE NAVIGATION IMPROVEMENT PROJECT BENEFIT-COST ANALYSIS PLAN A Channel and Basin Only PLAN B Channel, Basin and Anchorages Project Annual Costs $110,300 $253,200 Total Annual Benefits $736,900 $1,256,300 Net Annual Benefits $626,600 $1,003,100 Benefit-Cost Ratio Pursuing further Federal interest at Great Chebeague Island requires further Feasibility level study, and if still warranted, design and project implementation. Due to the limited project first cost these efforts could be continued under the Section 107 Continuing Authority, subject to further funding and cost-sharing. The New England District recommends that both Plan A and B improvements for the purpose of commercial navigation at Great Chebeague Island be further investigated under Section Views of the Non-Federal Sponsor (TBD) The Town of Chebeague Island, Maine, the non-federal sponsor, supports the recommended plan and is willing to participate in a cost-shared Feasibility Study of improvements at Great Chebeague Island. The Town and the CTC have provided assistance in the study, including attending the initial site visit, providing detailed data and information on the site, the community and fleet operations, and assisting in transportation during these initial studies. 12. Views of Federal and State Agencies and Interested Organizations The formal views of Federal and other State agencies will be solicited upon initiation of Feasibility Study efforts. The Maine State Dredging Team, including State and Federal agencies, and staff of the Maine Congressional delegation have been briefed on the study. No issues have been raised that would preclude navigation improvements. 13. Conclusion On the basis of this Initial Appraisal, it appears that sufficient benefits may for both Plans A and B exist to warrant continuation into the Feasibility Study. In order to proceed to that phase, the Government and the non-federal Sponsor, the Town of Chebeague Island will need to execute Feasibility Cost-Sharing Agreement (FCSA) setting forth responsibility for completing that study. That study would investigate improvements of varying scope to identify the optimal plan in the interest of national economic development consistent with the Corps environmental operating principles, and alternatives which may better match local needs and ability to pay. -16-

21 The costs of the Feasibility phase above the first $100,000 would be cost-shared 50/50 between the Government and the non-federal Sponsor. Completion of the study would take about two years subject to funding. If the final analysis indicates that Federal participation in project construction is feasible and in the Federal Government s interest, the Government will seek to enter into a Project Partnership Agreement (PPA) with the non-federal sponsor and seek cost- shared funds for project design and implementation. TABLE 7 GREAT CHEBEAGUE ISLAND, MAINE NAVIGATION IMPROVEMENT PROJECT PROJECT COST-SHARING Total Cost by Phase Federal Cost PLAN A CHANNEL AND BASIN ONLY Non-Federal Up-Front Cost Feasibility Study Cost $260,000 $180,000 $80,000 Plans & Specifications Cost $114,000 $102,600 $11,400 Construction Phase Cost $785,000 $706,500 $78,500 Post- Construction Reimbursement TOTAL $1,159,000 $989,100 $169,900 Total D&I Cost $899,000 $809,100 $89,900 $89,900 Ultimate D&I Cost (With Reimbursement) $719,200 $179,800 Ultimate Cost (With Reimbursement & Feasibility) $899,200 $259,800 PLAN B CHANNEL, BASIN AND ANCHORAGES Feasibility Study Cost $350,000 $225,000 $125,000 Plans & Specifications Cost $184,000 $165,600 $18,400 Construction Phase Cost $2,546,000 $2,291,400 $254,600 TOTAL $3,080,000 $2,682,000 $398,000 Total D&I Cost $2,730,000 $2,457,000 $273,000 $273,000 Ultimate D&I Cost (With Reimbursement) Ultimate Cost (With Reimbursement & Feasibility) $2,184,000 $546,000 $2,409,000 $671, Attachments Attachment A Pertinent Correspondence Attachment B Design and Cost Estimates Attachment C Economic Analysis -17-

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