3389 LCHD-ESS Section C - OCT2025.docx

The U.S. Army Corps of Engineers (USACE) maintains a minimum fleet that includes the hopper dredges ESSAYONS, YAQUINA, WHEELER, and MCFARLAND, pursuant to Public Law (PL) 95-269 (1978). These government hopper dredges play an important role in guaranteeing the ability of the Corps to deliver its navigation missions and enable safe, reliable, and effective waterborne transportation systems for vital national security, commerce, and recreation needs.

USACE manages the minimum hopper dredge fleet using accepted asset management principles, including a Plant Replacement and Improvement Plan (PRIP) that ensures financial capacity to fund replacement of vessels when needed.

The Corps has a long-term plan for recapitalizing its minimum fleet consistent with the financial obligations of the USACE dredge fleet. The plan is based on the importance of the minimum fleet mission, the age and operating condition of the vessels, and the capacity of the PRIP fund. Decommissioning of the old dredges will occur at the time of replacement.

B. ESSAYONS REPLACEMENT

The Marine Design Center (MDC) of USACE has issued this solicitation to acquire a new Large Class Hopper Dredge (LCHD-ESS) to replace the ageing Dredge ESSAYONS.

The new dredge shall have the following: 6,500 cubic yard capacity, diesel-electric power system, and azimuthing thruster propulsion.

The completed vessel will be placed in service with the Portland District of the U.S. Army Corps of Engineers (CENWP) and will be used by the District for operations as described in Specification Section C002. As discussed above, the ESSAYONS will be removed from service when the new vessel is in operation.

The completed vessel shall be ABS classed. As a United States dredge, the vessel construction, manning, and operation shall satisfy all requirements of the Jones Act/Merchant Marine Act of 1920.

The following performance-based specification and outlined operational requirements were identified to ensure the capability of the replacement ESSAYONS meets mission requirements within its Area of Responsibility (AOR).

The Large Class Hopper Dredge (LCHD-ESS) to be designed and delivered under this contract will become part of the USACE Minimum Fleet, and upon delivery, will be placed in operation on the West Coast under the United States Army Corps of Engineers Portland District.

The Dredge ESSAYONS began operations in 1982. After the dredge McFARLAND was placed in Ready Reserve status, the ESSAYONS was released from any operating limits and currently works approximately 240 days/year. From approximately April to November each year, the ESSAYONS helps maintain the entrance bars, rivers, and harbors on the coasts of Washington, Oregon, California, Alaska, and Hawaii. During the dredging season, the vessel works continuous 24-hour,7-day/week schedules.

The LCHD-ESS shall be designed with the performance characteristics necessary for dredging and discharging the hopper anywhere in its assigned area of responsibility (AOR). Seakeeping capabilities are especially critical within this AOR. Seakeeping refers to the ability of the vessel to operate in the environmental conditions (winds, waves, currents, etc.) that it experiences. The seakeeping performance criteria are based on ESSAYONS current motion response in the various mission locations. This represents the threshold for performance. The seakeeping performance of the vessel sets the envelope of environmental (wind and seaway) conditions in which the vessel may safely and effectively dredge. By maximizing this envelope, the vessel is presented with` the most opportunities to dredge at a given location and therefore execute the yearly dredging mission. To execute the mission, the dredge shall be designed to normally operate in 7-foot waves and typical maximum wave height of 14-foot.

The overall goal for the dredge is to execute any maintenance dredging that presents itself within the dredge ESSAYONS AOR. It is understood that there may be some trade-off between “optimum” under specified conditions and “range of operation” under more extreme conditions. During operations, the goal is to maximize production in terms of cubic yards of material removed. Production is based on a combination of hopper load and total cycle time. USACE has identified features that contribute to better overall operation that include:

· Maximized hopper loading capacity with 1.8 SG in hopper material.

· Maximized dredge maneuvering control and dredging performance in high current and wind condition as described in the specifications.

· Propulsion and Steering systems that together maximize maneuvering power (with the inclusion of the bow thrusters) and provide rapid response to propulsion and steering inputs.

· Ease of maintenance and equipment replacement while in dockside status.

· Minimized need for dry docking Power system redundancy and operational flexibility that precludes being completely out of service (operating at reduced dredging capacity while repairs are made) when there are individual component breakdowns.

Subparagraph B describes the current operations of the ESSAYONS and is mission which the LCHD-ESS shall fulfil. This information shall be used as design guidance for the LCHD-ESS.

B. Current ESSAYONS Dredge Operating Profile For background information about the operating profile of the existing vessel being replaced (ESSAYONS), the following dredging operations are provided based on historical use and are the situations considered most likely for future operations. However, actual usage may vary to include differing locations, dredging depth, material, distance to the disposal site, and potential upland disposal. Offerors shall utilize this information as the basis for the operating profile of the new dredge, in conjunction with the technical requirements in this solicitation.

Calendar and Schedule of Operations The ESSAYONS operates two complete crews on a rotating 14 day-on/14 day-off cycle. Once per 14 day cycle, the dredge will return to the pier or anchor for approximately 8 hours to exchange crews and complete miscellaneous repairs, resupply, or refueling activities.

The ESSAYONS dredging season typically runs from early-April to late-November. Outside of these months, the vessel undergoes an annual winter maintenance and repair season at a shipyard/drydock located on the West Coast or in Hawaii. Once the shipyard period is complete, the vessel transits back to its homeport in Portland, OR to complete any remaining maintenance tasks and to refit for the next dredging season. Prior to commencing full-production dredging operations, the ESSAYONS will typically undergo several days of sea trials and test dredging to ensure all systems are fully operational. These trials are historically conducted in the Columbia River around the Portland/Vancouver area (river miles 100 – 103).

Once trials are complete, the ESSAYONS will typically transit downstream in the Lower Columbia River to conduct 7 days of early season dredging. The early season dredging is used to address any critical shoaling that could lead to draft restrictions before large scale efforts of maintenance dredging begin in late-June to early-July.

After the Lower Columbia River, the ESSAYONS transits north along the West Coast to Grays Harbor, WA, the entrance channel to Aberdeen, WA, to conduct approximately 25 days of dredging in the bar and entrance channels.

Following Grays Harbor, the vessel will typically transit south to Humboldt Bay, CA to conduct approximately 10, but as many as 25, days of dredging. The number of days is dependent on availability and schedules.

Upon completion at Humboldt Bay, the ESSAYONS continues transiting south to the San Francisco Main Ship Channel. This location is the entrance channel for all marine traffic entering San Francisco Bay and in-bay ports continuing as far north as Sacramento, CA. Here the vessel will dredge for approximately 20 days.

Following the Main Ship Channel, the ESSAYONS transits in-bay to work 10 to 20 days at either the Richmond Outer Harbor, or further north in-bay at Pinole Shoal Channel in San Pablo Bay. These two projects alternate year-to-year due to environmental restrictions that limit hopper dredging to only one in-bay project per season.

Following completion of the in-bay work, the dredge transits back north to the Lower Columbia River to conduct approximately 20 to 30 days of dredging, predominantly consisting of removing rapidly migrating, steep sand waves.

In late-July, the vessel will break from working in the Lower Columbia River to transit south to Coos Bay, OR to conduct approximately 20 days of dredging.

After completing work in Coos Bay, the vessel transits back north to conduct approximately 40 days of dredging at the Mouth of the Columbia River.

While working in the Mouth of the Columbia River, the vessel will move upriver during times of foul weather. This change over from the Mouth to upriver can sometimes be for as little as a few hours.

Once complete with all work at the Mouth of the Columbia, typically around the first half of October, the vessel will move upriver to conduct approximately 40 days of advanced maintenance dredging (AMD) in the Lower Columbia River, between river miles ~15 to 70. AMD differs from earlier season dredging in the Columbia in that the shoaling is typically more uniform and continuous, as opposed to the steep, sporadic, and rapidly migrating sand waves. Following completion of all work in the Lower Columbia River, the dredge will tie up for the winter at the home dock in Portland, OR to start the winter maintenance and repair season.

Dredged Materials For this Contract, the following measurement classifications shall be used for calculation of dredging requirements:

Material Classification

Sand Medium Sand

Sand

Silt

(2000) 10-18 (2000- 1000) 18-35 (1000-500) 35-60 (500-250)

(125-62)

Most materials to be dredged by the LCHD-ESS AOR are silica sands with some unique materials listed in respective site details below. Additional information about the materials in the AOR is found in the reference document All Project Sediment Data Soil samples from each location may be provided to the Contractor during Phase I of the Contract by written request to the COR.

Operational Specifics For all coastal transits, the dredge will travel at transit speed with the hopper empty, but free flooded. Transit departure conditions include fully stocked stores, full fuel, and full potable water, with empty waste and sewage tanks.

At each location, the vessel will typically arrive at the dredging station, dredge with or without overflow (see specific sites below), transit to disposal site, bottom dump or pump out upland (see specific sites below), and then return to dredging station.

Four different disposal methods are used in the LCHD-ESS AOR.

Upland disposal – The vessel will connect the bow connection to a floating hose which is subsequently connected to a pipeline running ashore. The vessel will re-fluidize the hopper contents and use the onboard pumps to pump material ashore, typically for beneficial use. The vessel maintains station with its own propulsion systems while connected to the pipeline.

Point Placement – The vessel, once over the disposal site, will maintain station while material is deposited via the hopper bottom doors. This may occur in both deep and shallow waters. All dredging locations utilize some shallow disposal sites.

Thin Layer Placement – The vessel approaches a disposal site at slow speed (less than 2 knots) and once over the site, partially opens the hopper bottom doors to slowly disperse material over a pathway.

Gridded Placement – This method is used at nearshore disposal sites and utilizes the hopper bottom doors. The site is broken up into 500-foot by 500-foot cells in a grid arrangement. During each disposal cycle, the vessel must deposit dredge material into at least 10 of the cells. This operation requires the vessel to start and stop both dumping and maneuvering frequently to achieve the disposal site’s requirements.

All sites require varying degrees/means of turbidity monitoring.

Environmental Specifics Locations within the LCHD-ESS AOR exhibit a variety of wind, wave, current, and weather conditions. Much of the dredging occurs in inlets along Pacific Ocean Coast. Completing the yearly dredging quotas requires the vessel to regularly dredge in adverse conditions. Each location below includes information about the average and maximum wind speeds that the vessel will encounter during all steps of the dredging operation. These are expected to be seen at any encounter angle. Likewise, tidal and river current speeds vary throughout the AOR. While dredging and transiting, these currents are primarily encountered head-on or from the astern. However, some locations present significant cross currents encountered abeam while operating. These details are listed below for each respective location.

The LCHD-ESS AOR requires executing dredging in a variety of wave conditions. Each dredging location below includes the significant wave height that the vessel is required expected to regularly encounter and work in. Waves of this height are expected to be seen at any encounter angle.

Dredging Location Specifics The following primary dredging locations are listed in general order of criticality based on life, safety, commerce, as well as time spent at each location relative to total number of days worked in an average dredging season. The attributes described below may be used for selection and optimization of the vessel design. It is the Government’s assumption that vessel design criteria will be based on project constraints, by level of criticality, as listed below:

a. Columbia River, WA & OR – River Miles 3 to 106:

· Approximate Dredging Days/Year: 80 days Approximate Volume Dredged Annually: 1,600,000 cubic yards

· Dredging Material: Ranges from very coarse sand to very fine silt, with most of the material being classified as medium sand. Additionally, sediment within several areas of the Columbia River contain highly abrasive volcanic materials.

Project Depth: 43 – 48 feet Mean Lower Low Water (MLLW) Operational Significant Wave Height: < 2 feet

· Current: max of 3.5 knots, average of 2 knots Winds: max of 35 knots, average of 25 knots

· Distance to Disposal Site: max distance of 17 nm one way, average of 7 nm one way.

· Disposal Details: Point Placement and Thin Layer Placement

· Very shallow disposal sites.

Confined maneuvering space, as tight as the vessel’s principal dimensions.

· Operational Considerations:

Vessel must work amongst a high quantity of large transiting vessels. Two-way traffic is occurring around the dredge in a 600’ wide channel.

b. Mouth of the Columbia Bar, WA & OR:

· Approximate Dredging Days/Year: 40 days

· Approximate Volume Dredged Annually: 1,350,000 cubic yards

· Dredging Material: Ranges from medium sand to clay, with most of the material being classified as fine sand.

· Project Depth: 55 – 60 feet MLLW

· Significant Operational Wave Heights: 14 feet

· Current: max of 7 knots, average 3 knots

· Winds: average of 35 knots. Max of 50 knots.

· Distance to Disposal Site: 5 - 7 nm one way

· Disposal Details: Gridded Placement Operational Considerations:

· Dredging operations at the Mouth of the Columbia River Bar are undertaken as weather windows allow. During approximately 10% of the total scheduled time onsite, the weather and sea conditions are so severe (winds more than 50 knots and seas with more than a 14’ significant wave height) that the vessel ceases dredging operations. During this time, the vessel will rapidly move upriver to work dredge sites in a more protected location.

c. San Francisco, CA – Main Ship Channel:

· Approximate Dredging Days/Year: 20 days

· Approximate Volume Dredged Annually: 450,000 cubic yards

· Dredging Material: Ranges from medium sand to clay, with most of the material being fine sand.

· Project Depth: 55 – 57 feet MLLW

· Significant Operational Wave Heights: 10 feet

· Current: 3 knots

· Winds: 30 knots

· Distance to Disposal Site: 8 – 10 nm one way

· Disposal Details: Point Placement Clay materials are highly adhesive to the hopper causing long disposal times (often greater than 30 minutes) Cross currents up to 1.5 kts at disposal site that the vessel must maintain station against.

· Operational Considerations:

Dredging operations occur during periods of extended dense fog. Visibility regularly limited to ¼ nmi.

· Vessel must work amongst two-way heavy commercial and recreational traffic.

· Environmental Considerations:

· California Air Resource Board regulation adherence required.

High quantity of marine mammals and whales. Vessel must abide by NOAA imposed speed restrictions.

· Specified zones for discharging treated black water.

d. San Francisco, CA – In Bay – Richmond:

Approximate Dredging Days/Year (approximately every other year): 20 days Approximate Volume Dredged Annually: 450,000 cubic yards

· Dredging Material: Ranges from very coarse sand to clay

· Project Depth: 42 - 48 feet MLLW

· Significant Operational Wave Heights: <2 feet

· Current: 5 knots maximum, 3 knots average

· Winds: 20 knots

· Distance to Disposal Site: 5 - 7 nm one way

· Type of Disposal: Point Placement Operational Considerations:

· Vessel must work amongst heavy commercial and recreational traffic.

The channel is subject to One-way traffic – Regulated Navigation Area (RNA). This requires the dredge to idle for frequent 1-hour durations while opposing traffic passes.

Environmental Considerations:

· California Air Resource Board regulation adherence required.

Dredge must employ biological monitoring for long fin and delta smelt.

· Dredging is not allowed sooner than 1JUN every year.

· Renewable fuel requested by state in accordance with CARB.

e. San Francisco, CA – In Bay – Pinole Shoal:

Approximate Dredging Days/Year (approximately every other year): 20 days

· Approximate Volume Dredged Annually: 250,000 cubic yards

· Dredging Material: Ranges from coarse sand to clay, with most of the material being fine sand.

· Project Depth: 42 feet MLLW

· Significant Operational Wave Heights: 4 feet

· Current: 3 knots

· Winds: 20 knots

· Distance to Disposal Site: 5 – 7 nm one way

· Disposal Details: Point placement Operational Considerations:

· Vessel must work amongst heavy commercial and recreational traffic.

The channel is subject to One-way traffic – Regulated Navigation Area (RNA). This requires the dredge to idle for frequent 1-hour durations while opposing traffic passes.

· Environmental Considerations:

· California Air Resource Board regulation adherence required.

· Dredge must employ biological monitoring of long fin and delta smelt.

· Dredging not permitted prior to 1JUN

· Renewable fuel requested by state in accordance with CARB.

f. Grays Harbor, WA:

· Approximate Dredging Days/Year: 25 days

· Approximate Volume Dredged Annually: 650,000 cubic yards

· Dredging Material: Ranges from very coarse sand to clay

· Project Depth: 38 - 50 feet MLLW

· Significant Operational Wave Heights: 10 feet

· Current: max of 5 knots, average of 3.5 knots at all encounter angles.

· Winds: max of 45 knots, average of 20 knots

· Distance to Disposal Site: max of 5 nm one way

· Disposal Details: Point Placement Shallow disposal sites with large, typically 6’ swells.

· Operational Considerations:

· None.

Environmental Considerations:

Biological entrainment sampling for green sturgeon required after 1MAY for all dredging operations.

g. Coos Bay, OR:

· Approximate Dredging Days/Year: 20 days

· Approximate Volume Dredged Annually: 600,000 cubic yards

· Dredging Material: Ranges from medium sand to medium silt, with most of the material being medium sand

· Project Depth: 53 ft MLLW

· Significant Operational Wave Heights: 10 feet

· Current: max5 knots, average 3 knots encountered at all encounter angles.

· Winds: 15 knots

· Distance to Disposal Site: 3 nm one way

· Disposal Details: Point Placement

· Operational Considerations:

· Vessel must work in dense fog for prolonged periods of time. Visibility often limited to ¼ nmi.

· Heavy small boat traffic often requires additional lookouts and transiting at lower speeds. High reliance on short range radar and thermal camera for situational awareness.

· Extremely confined channel (300’ wide) where the vessel will dredge in close proximity to jetty/structures, within 100’.

Environmental Considerations:

None

h. Humboldt Bay, CA:

· Approximate Dredging Days/Year: 25 days

· Approximate Volume Dredged Annually: 900,000 cubic yards

· Dredging Material: Ranges from very coarse sand to clay

· Project Depth: 38 - 51 feet MLLW

· Significant Operational Wave Heights: 12 feet

· Current: max of 4 knots

· Winds: 30 knots

· Distance to Disposal Site: 3 nm one way

· Disposal Details: Point Placement, Gridded Placement

· Operational Considerations:

High amount of small boat traffic.

· Confined channel (600’ wide) and required work in close proximity (100’) to jetty/structures.

· Environmental Considerations:

· California Air Resource Board regulation adherence.

· Zero discharge of vessel fluids.

The AoR includes a few locations infrequently worked by the ESSAYONS. These locations do not require the new dredge to be configured differently or have capability beyond that discussed above except as noted below:

i. Honolulu, HI:

· Mobilization from U.S. Moorings Portland, OR to Honolulu, HI is approximately 3,000 nautical miles.

· Operational and Environmental Considerations:

· Turtle deflectors required.

· Varied turbidity limits.

Abrasive coral dredge material.

· Whale and mammal speed restrictions.

· Frequency of working this location is once in 10 – 15 years. Last time the ESSAYONS was at this location was 2016.

j. Anchorage, AK:

· Mobilization from U.S. Moorings Portland, OR to Anchorage, AK is 1430 nautical miles.

· Operational and Environmental Considerations:

· Glacial silt – fine grained sediment deposited by melting glaciers

· Frequency of working this location is once in 15 - 20 years. Last time the ESSAYONS was at this location was 2014.

k. Panama Canal Transit to U.S. East & Gulf Coasts:

The vessel shall have the ability to transit the original Panama Canal (PANAMAX).

C. SPECIFIC REQUIREMENTS

The dredge shall be designed and built according to the specifications throughout this contract. The following summarizes some of the highest-level performance requirements for the LCHD-ESS.

The dredge shall be designed and built in accordance with the most recent California Air Resource Board (CARB) Commercial Harbor Crafts Regulations. Adherence to these regulations is required for all operations in the state of California.

Principal Characteristic Requirements The LCHD-ESS shall have the following characteristics:

Length Between Perpendiculars: 280 to 335 feet. Maximum length overall, including appendages, shall not exceed 381 feet.

Beam: As best suits the design, within PANAMAX requirements.

Hull Form: optimized for seakeeping in the vessel AOR wave conditions as described in Contract Paragraph C165 while still meeting hopper capacity and draft requirements.

Air–Draft: 110 feet maximum in the lightest seagoing condition. Folding masts may be used to meet this requirement.

Loaded Draft at maximum deadweight capacity with hopper full of 6,500 cubic yards of SG 1.8 material: 26 feet or less.

Freeboard at the Loaded Draft shall be as required by the regulatory requirements to permit all dredging operations in significant wave heights of 14 feet.

Hopper Capacity at maximum overflow height: 6,500 cubic yards.

Accommodations for a crew of 28 persons and 4 environmental fish observers during operations. The vessel shall have the accommodations as defined in Contract Paragraph C201, as a minimum.

Performance Requirements Speed:

· Transit speed, hopper empty, minimum 14 knots.

· Transit speed, hopper full, minimum 10 knots.

Shallow Water: for transit conditions water depth shall be taken as 3 times the Loaded Draft.

· Dredging speed, hopper full (minimum 2 knots into a 7-knot current) Dredging Depth, reference to mean water surface: 38 to 85 feet at all operational dredging drafts.

Weathervaning in a 3-knot current is used from the single point buoy during pump out. Propulsion power adequate to safely weathervane, and to prevent excessive tension on the floating hose system.

Hopper Loading Time: Capable of filling hopper with 6,500 cubic yards of 1.8 SG material in no more than 55 minutes when dredging at 85 feet.

Hopper Unloading Time: Pump Out over the bow through hose (Contractor supplied) and pipeline (Government supplied) to landfill with a geodetic head of 75ft, over a length of 1.5 miles in no more than 120 minutes.

Environmental Design Temperatures:

Outside Air (cooling season): 100 F Outside Air (heating season): 30 F Seawater Temperature (cooling): 80 F Seawater Temperature (heating): 37 F Tankage shall be sized to execute zero-discharge operations, as discussed below, the endurance missions discussed later in this paragraph, and in accordance with the requirements of Contract Paragraph C130.

While in a zero-discharge operation, the vessel will retain all blackwater, greywater, bilge, and oily bilge water onboard. There will be no overboard discharge from the vessel other than that associated directly with dredging (dredge material, jetting, and flushing water) or deck drains. Retention of water in the bilges shall not be considered in this capacity. The vessel shall be provided with the tankage sufficient for 18 days of zero-discharge operation.

Endurance Mission Profiles: The vessel shall be capable of executing the design endurance operations. The approximately 18-day period working period and extended transit profile shall be used for purposes of sizing fuel/DEF storage requirements and other pertinent design criteria. These missions shall be accomplished with a reserve of at least 10% fuel and consumables. No boundary of an oil tank shall be integral with the side plate or bottom plate of the hull, nor with the sloped side plates of the hopper.

Endurance Operating Mission Profile:

The vessel departs the pier in the General Condition, No Cargo-Departure condition (see Contract Paragraph C160). The full crew are aboard. All consumables are at 100% levels. All waste or waste product holding tanks are empty. The hopper doors are closed but the hopper is free-flooded with seawater.

The vessel transits 600 nautical miles at 14 knots from a notional pier to the Mouth of the Columbia River. Transit is a 24-hour continuous operation; duration approximately 43 hours. The vessel transits near coastal in calm seas.

Upon arrival at the dredge site on the Mouth of the Columbia River, the vessel will complete dredging operations continuously, 24-hours per day, to accomplish 120 dredging cycles, yielding 780,000 cubic yards of SG 1.8 material production.

A typical dredging cycle shall consist of the following operations.

Hopper fill:

The vessel deploys both drag arms in 65 feet of water and makes a speed of two knots over ground against a 7-knot current. There are no cross currents or head winds. The hopper is free-flooded at the start of the operation. The hopper is full at the maximum capacity of 6,500 cubic yards of 1.8 SG material at the end of the operation. The material being dredged consists of fine sand. The time to complete the hopper filling operation shall be based on the Contractor’s dredge system pumping rate but in no case shall be no longer than 55 minutes.

Transit to disposal site:

The vessel transits to the disposal site with the full hopper load, with the drag arms secured, at a through-water speed of 10 knots. The one-way distance to the disposal site is 8 nautical miles.

Disposal:

The vessel disposes of the full hopper load through the bottom doors. The jet pumps and hopper flushing pump run at their rated operating points. The vessel conducts thin layer placement disposal, maintaining a forward speed of two knots through the water. No current or crosswinds are encountered. The operation shall be assumed to take 30 minutes.

Return transit to dredging site:

The vessel transits back to the dredge site with the hopper empty but free-flooded at a through-water speed of 14 knots. The one-way distance is 8 nautical miles.

The cycle repeats until the vessel has completed the 120 cycles, at which time, the vessel shall drop anchor and remain at an anchorage for 48 hours to conduct a crew change and perform routine maintenance. The vessel’s power plant shall continue to support the hotel and auxiliary loads necessary to maintain a full crew and at-anchor operations.

The vessel then hauls anchor and transits upriver to its home port in Portland, Oregon. The transit is assumed to be 100 nautical miles and shall be accomplished at a speed of 14 knots. The hopper shall be considered empty but free-flooded. Once tied up at the pier, the plant is shut down and the mission is considered complete.

Endurance Transit Mission Profile:

The vessel shall also be capable of long-distance deployment. To execute this mission, the vessel departs the pier in the General Condition, No Cargo-Departure condition. The full crew are aboard. All consumables are at 100% levels. All waste or waste product holding tanks are empty. The hopper doors are closed but the hopper is free flooded with seawater.

The vessel transits 5,000 nautical miles at a speed of 14 knots through water. Seas and winds are calm. Upon arrival at the destination, the mission is considered complete.

Critical Design Conditions: In addition to the vessel’s speed requirements, the LCHD-ESS shall be capable of executing the following design conditions as it applies to propulsion, powering, redundancy, and relevant aspects of the vessel’s design.

Critical Dredging Condition- dredging (without bow thruster) in 60-foot water depth, into 7 knot current with 2 knots speed over ground, with both dragarms down, dredge and jet pumps at power for the design minimum hopper fill time, and hopper full with 1.8 SG material. No wind, waves, or crosscurrent.

Reduced Dredging Condition- dredging (without bow thruster) in 60-foot water depth, into 4 knot current with 2 knot speed over ground. One drag arm and dredge pump in use with the largest generator offline. Jet pumps arranged to achieve normal draghead jet pressure. 15 knot crosswind and no waves.

Cross-Current Tracking Condition – dredging at 2 knots over ground without bow thruster in 60-foot water depth, with 3 knot cross current and 35 knot cross wind (same direction), with both dragarms down, dredge and jet pumps at power for the design minimum hopper fill time, and hopper full with 1.8 S.G. material. No waves.

Cross Wind Tracking Condition - dredging without bow thruster in 60-foot water depth, into 4 knot current and 50 knot cross wind, with both dragarms down, dredge pumps at power for the design minimum hopper fill time, and hopper full with 1.8 S.G. material. No waves.

Critical Position, Dumping Condition – dumping via bottom doors in 40-foot water depth, jet and flushing pumps operating at rated points maintaining station against 25 knot cross wind, 2 knot cross current, and 6’ waves with a 6.25s period in the same direction.

Critical Position, Pumping Condition – pumping ashore via bow connection, dredge/jet/flushing pumps running at design point for minimum hopper unload time through 1.5-mile pipeline with 75-foot geodetic head, maintaining station against 20 knot crosswind and 3 knot cross current in the same direction. No waves are present.

Main Machinery Requirements Power System: Diesel-electric. A series of diesel-powered generator-sets connected to a common bus shall provide power for all vessel operations. All diesel engines shall meet the current U.S. environmental emissions requirements and the California Air Resource Board regulations. Diesel engines shall run on ultra-low sulfur fuel and adhere to all CARB required fuel regulations. Diesel engines and the connected generators shall be rated for continuous power output.

Propulsion: Twin or triple screw azimuthing thrusters (Z or L-drive). Thrusters shall be removable and replaceable with vessel afloat and without drydocking. Thrusters shall utilize fixed pitch propellers with propeller nozzles. Propulsion shall utilize electric motors powered by the vessel diesel-electric system. Propulsion power shall be sufficient to achieve the design speeds and critical conditions above.

Bow Thrusters: Two variable-speed, fixed-pitch bow thrusters shall arranged to be effective in dredging conditions with minimum bow draft. The bow thrusters shall have a minimum combined total capacity of 1,000 horsepower.

The vessel shall and its thruster design, as it relates to hull form features and placement on the hull, shall consider maneuverability to be equal in importance to transit performance. The system shall also include DP/DT functionality to maintain dredge track lines and hold station while discharging to pipelines or dumping (see Contract Paragraph C121 and C608).

Dredging System Requirements The Dredging Systems shall consist of:

Drag Arms: 2 drag arms, one each side, with drag heads that are equipped with water jets, adjustable visors, and turtle exclusion device (TED) (See Contract Paragraph C510 & 511).

Dredge Pumps: One inboard dredge pump per drag arm. Over the bow pump out capable (See Contract Paragraph C504).

Dredge pump spherical clearance shall be no less than 12 inches.

Sliding Trunnions (See Contract Paragraph C510).

Bottom Dumping: multiple doors, hydraulically actuated (See Contract Paragraph C514). Bottom doors shall be designed such that the doors can be fully opened when the water depth 40 feet. For dumping in shallower waters, proportional opening of the doors shall be possible.

Hopper pump out collection system (See Contract Paragraph C520).

Jetting system to supply high pressure water to the drag heads to hydraulically assist excavation during dredging and to the hopper to fluidize material during unloading (See Contract Paragraph C518 and C519).

Adjustable overflow system and anti-turbidity features (See Contract Paragraph C516).

Biological Sampling Devices (See Contract Paragraph C511).

Automation, Monitoring, & Control System Requirements Vessel: shall have a machinery control, monitoring, alarm system that meets USCG periodically unattended machinery space and ABS Automation Centralized Control Unmanned (ACCU) requirements.

Dredging System: shall have a highly-automated dredging control system that has at a minimum, the following capabilities, and provides output in accordance with USACE’s Dredge Quality Management (DQM) program (See Contract Paragraph C524).

Drag Arm Position Sensing Hopper Fill Level Sensing Overflow Position Sensing Hull Draft Sensing Hull Speed Over Bottom Sensing Hull Speed Through Water Sensing Vessel Position and Track Sensing Production Monitoring (velocity & density) Sensing Dredge Pump: RPM, Inlet Vacuum, and Discharge Pressure Sensing Jetting Pump: RPM, Inlet Vacuum, and Discharge Pressure Sensing Automated Drag Arm, Drag Head, Dredge Pump, & Overflow Control for:

Most efficient production Least turbidity production Fastest hopper fill production Draft limited production Pump out pressure & velocity control Zero overflow locations Vessel Maneuvering Control for:

Dredge track keeping Dredge station keeping

D. SPECIAL FEATURES

None.

E. DELIVERABLES

None.

F. STANDARDS

See contract Paragraph C003

The following list contains the various standards referenced throughout Section C of the Specification.

B. REQUIREMENTS

The Contractor shall ensure that the design complies with all applicable requirements of ABS, USCG, SOLAS, EM 385-1-1, and this Specification.

Regardless of dates or years given below, the Contractor shall apply the most recent version available at the time of Contract Award for all Standards and References.

Where references are made throughout Section C to specific sections of a standard or document, this is intended to highlight key information but does not exclude any other relevant portions of the document. This list of standards is not intended to include any standard that may be incorporated by reference by ABS or USCG. Where conflicts between this Contract, the cited standards, and regulatory body rules are identified, these should be brought to the attention of the COR for resolution using the RFI process laid out in Contract Paragraph H03.

Where standards are not provided for the design or selection of equipment, the Contractor may propose standards for approval by the COR.

C. SPECIFIC REQUIREMENTS

None.

D. SPECIAL FEATURES

The vessel shall meet the most current regulations as defined by California Air Resource Board’s (CARB) Airborne Toxic Control Measures for Commercial Harbor Craft. For more details, see Contract Paragraph C004.

E. DELIVERABLES

None.

F. STANDARDS

· ABS

· ABS Rules for Building and Classing Marine Vessels ABS Rules for Building and Classing High Speed Vessels ABS Rules for Survey After Construction – Underwater Inspections in Lieu of Drydocking Surveys

· Guidance Notes on Cathodic Protection of Ships

· Guidance Notes on Control of Harmonics in Electrical Power Systems Guidance Notes on Ergonomic Design of Navigation Bridges

· Guidance Notes on SafeHull Finite Element Analysis for Hull Structures

· Guidance Notes on the Application of Ergonomics to Marine Systems

· Guide for Ballast Water Exchange Guide for Bridge Design and Navigational Equipment/Systems

· Guide for Certification of Lifting Appliances

· Guide for Crew Habitability on Workboats

· Guide for Dynamic Positioning Systems

· Guide for Hull Survey for New Construction Guide for ‘SafeHull-Dynamic Loading Approach’ for Vessels Guide for Spectral-Based Fatigue Analysis for Vessels Guide for Ergonomic Notations

API

Manual of Petroleum Measurement Standards, Standard Chapter 2, Section 8A

ASHRAE

ANSI/ASHRAE Standard 26-2010, Mechanical Refrigeration and Air Conditioning Installation Aboard Ships Handbook – HVAC Systems and Equipment

ANSI

A2.4 Standard Symbols for Welding, Brazing, and Nondestructive Examination

· Z308.1, Minimum Requirements for Workplace First Aid Kits and Supplies

· Z385.1, Emergency Eyewash & Shower Standard

ASME/ANSI

B16, Standards for Pipes and Fittings B36.10-18, Welded and Seamless Wrought Steel Pipe B36.19-18, Stainless Steel Pipe PTC 19.3 TW – 2016, Thermowells

ASME

ASME B16.47-2020, Large Diameter Steel Flanges: NPS 26 through NPS 60, Metric/Inch Standard B30.7-21, Winches B30.30-23, Ropes Boiler and Pressure Vessel Code, Code for Unfired Pressure Vessels

· ASTM

A53-24, Standard Specification for Pipe, Steel, Black, and Hot-Dipped, Zinc-Coated, Welded and Seamless A106-19a, Standard Specification for Seamless Carbon Steel Pipe for High-Temperature Service A307-21, Specification for Carbon Steel Bolts, Studs, and Threaded Rod A312/A312M-22 Standard Specification for Seamless, Welded and Heavily Cold Worked Austenitic Stainless Steel Pipes ASTM A320-22, Standard Specification for Alloy-Steel and Stainless Steel Bolting for Low-Temperature Service A781-06 Standard Specification for Casting, Steel and Alloy, Common Requirements for General Industrial Use B88-22, Standard Specification for Seamless Copper Water Tube B466-18, Standard Specification for Seamless Copper-Nickel Pipe and Tube D178-22, Standard Specification for Rubber Insulating Matting D429-14, Standard Test Methods for Rubber Property – Adhesion to Rigid Structures D4060-19, Standard Testing Method for Abrasion Resistance of Organic Coatings by the Taber Abraser F683-23A, Standard Practice for Selection and Application of Thermal Insulation for Piping and Machinery F708-24, Standard Practice for Design and Installation of Rigid Pipe Hangers F722-18, Standard Specification for Welded Joints for Shipboard Piping Systems F856-97, Standard Practice for Mechanical Symbols, Shipboard–Heating, Ventilation, and Air-Conditioning (HVAC) F906-85, Standard Specification for Letters and Numerals for Ships F994-86, Standard Specification for Design and Installation of Overboard Discharge Hull Penetration Connections F998-12, Standard Specification for Centrifugal Pump, Shipboard Use F1000-21, Standard Practice for Piping System Drawing Symbols F1085-19, Standard Specification for Mattress and Box Springs for Use in Berths in Marine Vessels F1155-10, Standard Practice for Selection and Application of Piping System Materials

F1244-08, Standard Specification for Berths, Marine F1321-21, Standard Guide for Conducting a Stability Test to Determine the Light Ship Displacement and Centers of Gravity of a Vessel F1510-21 Standard Specification for Rotary Positive Displacement Pumps, Ships Use F1511-18, Standard Specification for Mechanical Seals for Shipboard Pump Applications G21-15, Standard Practice for Determining Resistance of Synthetic Polymeric Materials to Fungi

CARB

17 CCR, Division 3, Chapter 1, Subchapter 7.5, Section 92118.5 Airborne Toxic Control Measures for Commercial Harbor Craft

· Department of Defense MIL-STD-464C, Interface Standard, Electromagnetic Environmental Effects, Requirements for Systems MIL-STD-1310H, Standard Practice, Shipboard Bonding, Grounding, and Other Techniques for Electromagnetic Compatibility, EMP Mitigation and Safety

· Manual of Naval Preventive Medicine (NAVMED) P-5010

· EPA

800-R-11-002, Environmentally Acceptable Lubricants 33 USC 1251 et seq., Clean Water Act, Section 312

40 CFR

Part 141, National Primary Drinking Water Regulations Part 1042, Control of Emissions from New and In-Use Marine Compression-Ignition Engines and Vessels

IACS

IACS Guide No. 47, Shipbuilding and Repair Quality Standard

· IEC

Publication 60092:2025, Electrical Installations in Ships Specification 60794-2:2017, Optical Fiber Cables – Part 2: Indoor Cables Standard 60529:2013, Degrees of Protection Provided by Enclosures (IP Code) Standard 60945:2002, Maritime Navigation and Radiocommunication Equipment and Systems Standard 61537:2023, Cable Management

· IEEE

45-2019, Recommended Practice for Electric Installations on Shipboard 1584-2018, Guide for Performing Arc-Flash Hazard Calculations C95.1-2019, Standard for Safety Levels with Respect to Human Exposure to Electric, Magnetic, and Electromagnetic Fields, 0 Hz to 300 GHz C95.2-2018, Standard for Radio-Frequency Energy and Current-Flow Symbols

IMO

Convention on the International Regulations for Preventing Collisions at Sea, 1972 (COLREGs) International Code for Fire Safety Systems (FSS Code) International Code of Signals International Convention for the Prevention of Pollution from Ships, 1973 (MARPOL) International Convention for the Safety of Life at Sea, 1974 (SOLAS) International Convention on Load Lines, 1966 IC874E, International Code on Intact Stability 2008 MSC.1/Circ.1331, Guidelines for Construction, Installation, Maintenance and Inspection/Survey of Means of Embarkation and Disembarkation Resolution A.382(X), Magnetic Compasses, Carriage and Performance Standards

· Resolution A.424(XI), Performance Standards for Gyro Compasses

· Resolution A.694(17), General Requirements for Shipborne Radio Equipment Forming Part of the Global Maritime Distress and Safety System (GMDSS) and for Electronic Navigational Aids Resolution A.1045(27), Pilot Transfer Arrangements Resolution A.1108(29), Amendments to the Recommendation on Pilot Transfer Arrangements (Resolution A.1045(27))

· Resolution MEPC 235(65), Amendments to the Annex of the Protocol of 1978 Relating to the International Convention for the Prevention of Pollution from Ships, 1973

· Resolution MSC.116(73), Performance Standards for Marine Transmitting Heading Devices (THDs) Resolution MSC.302(87), Performance Standards for Bridge Alert Management Resolution MSC.333(90), Adoption of Revised Performance Standards for Shipborne Voyage Data Recorders (VDRs) Resolution MSC.494(104), Resolution to the Performance Standards for Shipborne Voyage Data Recorders (VDRs) (Resolution MSC.333(90))

· ISO

Standard 484-1, Shipbuilding – Ship Screw Propellers – Manufacturing Tolerances Standard 8861, Shipbuilding – Engine Room Ventilation in Diesel-Engined Ships Standard 8728, Ships and Marine Technology – Marine Gyro-Compasses

NFPA

NFPA 70, National Electrical Code

NEMA

MG 10008-2022 NEMA Premium Efficiency Motors (600 V or Less)

NMEA

NMEA-20000183, Standard for Interfacing Marine Electronic DevicesModern Marine Interface Standard; CAN Based Fata Communication Vessel Systems Integration

· NSRP

· NSRP 0490, Industry Standards for Hull Structural Penetration Design

· OSHA

29 CFR

Part 1910, Occupational Safety and Health Standards Part 1915, Occupational Safety and Health Standards for Shipyard Employment Part 1918, Safety and Health Regulations for Longshoring Part 1919, Gear Certification Panama Canal Authority OP Notice to Shipping N-1 Vessel Requirements

· SAE

AMS-STD-595, Colors Used in Government Procurement

· SAWE

RP M-2:2009, Standard Coordinate Systems for Reporting Mass Properties of Marine Vehicles STD M-4:2021, Supplier Weight Control for the Marine Industry RP M-7:2017, Weight Control Technical Requirements for MSC and Similar Ships, Commercial Ships, and Other Small Craft RP 14:2001, Weight Estimating and Margin Manual for Marine Vehicles RP M-5:2009, Weight Distribution and Moments of Inertia for Marine Vehicles

SMACNA

HVAC Systems Duct Design

SNAME

Harrington, Roy L. (1992). Marine Engineering, New York: The Society of Naval Architects and Marine Engineers T&R Bulletin 3-47, Guide for Sea Trials T&R Bulletin 4-7, Thermal Insulation Report T&R Bulletin 4-16, Recommended Practices for Ship Heating, Ventilation & Air Conditioning Design Calculations

· SSPC

· SP-10, Near White Metal Blast UL Solutions UL 67, Panelboards UL Standard 489 “Molded-Case Circuit Breakers, Molded-Case Switches, and Circuit Breaker Enclosures” UL Standard 498, Attachment Plugs and Receptacles UL 924, Standard for Emergency Lighting and Power Equipment UL Standard 1066 “Power Circuit Brakers up to 1000VAC and 1500 VDC Used in Enclosures” UL 1104, Standard for Marine Navigation Lights

· USACE

EM 385-1-1, Safety and Health Requirements Manual ER 385-1-100, Arc Flash Hazard Program ER 385-1-89, Hearing Conservation Program ER 1130-2-500, Work Management Policies EP 1130-2-500, Work Management Guidance and Procedures USACE Sea Turtle Deflector Checklist for Hopper Dredges for USACE and USACE/Army-permitted projects

· United States Code Jones Act (USC 55101 et seq., USC 55109)

· USCG

DR-68, Guidelines for the Assignment of Reduced Freeboards for Dredgers

· MSC Guidelines for Watermist Fire Suppression Systems E1-03 MSC MTN 04-95, Lightship Change Determination Navigation Rules and Regulations NVIC 02-89, Guide for Electrical Installations on Merchant Vessels and Mobile Offshore Drilling Units Procedure E2-06, MSC Guidelines for Electrical Load Analysis

33 CFR

· Subchapter O, Pollution

· Part 104, Maritime Security: Vessels Part 164, Navigation Safety Regulations

46 CFR

· Subchapter F, Marine Engineering

· Subchapter G, Documentation and Measurement of Vessels

· Subchapter I, Cargo & Miscellaneous Vessels

· Part 69, Subpart B – Convention Measurement System

· Part 69, Subpart C – Standard Regulatory Measurement System

· Subchapter J, Electrical Engineering

· Subchapter Q, Equipment, Construction, and Materials

· Subchapter S, Subdivision and Stability Subchapter W, Lifesaving Appliances and Arrangements

The Contractor shall be responsible for preparing all necessary drawings and calculations, obtaining necessary regulatory body reviews and approvals, obtaining necessary inspections and surveys during construction and for the classing and certification of the vessel as follows:

B. REQUIREMENTS

ABS Classification

a. ABS Rules for Building and Classing Marine Vessels The vessel shall be designed, built inspected, and tested in accordance with the latest version of the ABS Rules and shall be Classed as follows: “Maltese Cross ✠A-1, Trailing Suction Hopper Dredger (Maximum Significant Wave Height 4.3M and 50 miles from Shore in Dredging Mode), Ⓔ, Maltese Cross ✠AMS, Maltese Cross ✠ ACCU

b. ABS Guide for Crew Habitability on Workboats The vessel shall be designed and built in accordance with the ABS Guide for Crew Habitability on Workboats, Habitability (HAB(WB)) and shall receive such notation upon completion of all tests and trials.

c. ABS Rules for Survey After Construction – Underwater Inspections in Lieu of Drydocking Surveys The vessel shall be designed and built in accordance with the requirements and recommendations in the ABS Rules for Survey After Construction – Underwater Inspections in Lieu of Drydocking (UWILD) Surveys (Part 7, Appendix 1). This shall include submission of all required plans and data to ABS for review and approval, and coordination with ABS to inspect the vessel prior to launch. The Contractor shall provide UWILD hull marking drawing (see Contract Paragraph C460) and initial video inspection prior to launch. The Contractor shall obtain the UWILD notation from ABS for the vessel and shall ensure compliance with ABS requirements for this notation.

d. ABS Guide for Certification of Lifting Appliances Cranes and lifting equipment on the vessel shall be included in the ABS Register of Lifting Appliances under this Guide with the additional class notation CRC (SC-PL). Note that this does not include dragarm handling system or internal hoists for equipment/material handling.

e. International Convention on Load Lines (see Contract Paragraph C140 for additional details) The Contractor shall employ ABS to survey the vessel for compliance with the International Convention on Load Lines 1966, as amended.