B08-Attachment_4-SOW_Penobscot_River_Loop_Bridge_7221.pdf

STATEMENT OF WORK (SOW)

Katahdin Woods and Waters (KAWW) National Monument Replace Substandard Culverts and Bridges, Penobscot

County, Maine PMIS KAWW 333899A- Bridge Restoration East Branch Penobscot River Loop

Road T5-R8 WELS #7221

1.0 Background

Project is located in the National Park Service unit, Katahdin Woods and Waters National Monument (KAWW), located in Penobscot County of Northern Maine.

Katahdin Woods and Waters National Monument includes more than 80,000 acres and several hundred miles of aggregate-surface logging roads customary to the Maine Northern Woods. This contract will repair a bridge system with another open channel bridge system within KAWW to facilitate Atlantic Salmon passage. Crossing #7221 consists of an existing substantial bridge which is insufficient in size presenting a potential barrier to aquatic organism passage to the headwaters of the East Branch Penobscot River.

2.0 Scope

This contract requires the contractor to provide all tools, labor, equipment, supervision, transportation, and materials necessary to remove an existing bridge system and relace with new. Work is to be done in accordance with all existing Federal, State, and local codes.

The proposed bridge will have a clear span of 32 feet and an open area (capacity) of about 132 square feet, as compared with the current bridge with only ≈45 square feet.

The abutments of the proposed bridge deck will sit up and out of the way of scour forces, with banks heavily armored by a thick layer of angular rock. The bridge deck will sit on 16' long x 2' x 2' concrete footings/beam seats. The deck must be capable of carrying full road loads (HS-25 rated), and will likely consist of an 18" high, steel 5-I-beam superstructure with steel-reinforced concrete deck panels fastened to the I-beams. The bridge will contain banks inside that connect to and match existing stream banks, which will consist of 12" - 18" rock to protect the abutments and filled in/mixed with a 6"-minus mixture with sufficient volume of fines to fill voids in the larger rock and create banks passable by terrestrial animals. To provide sufficient hydraulic capacity, the bridge deck will be set to provide a raised road elevation of 613', requiring ≈40 yards of gravel fill for approximately 50'.

3.0 Objectives

The objective of this contract is to fully replace a bridge system to full working order and to facilitate Atlantic Salmon fish passage within KAWW.

4.0 Tasks

Tasks include:

• Remove existing bridge system.

• Install open channel bridge structure according to specifications.

Repair / Replace Bridge: Bridge is on the East Branch Penobscot River Loop Road 1.5 miles from HWY 159 in T5-R8 WELS in Penobscot County – See Attachment 1, Location Map and Specifications.

1. Bridge - Repair and replace road bridge work includes, but is not limited to, removal of damaged concrete substructures, fabrication of replacement concrete substructures, layout, inlet/outlet dissipation, headwalls, tail walls, and re-construction of existing open channel concrete substructures, stream simulation, gravel roadway reconstruction, and bridge approach work. Bridge repair and rehabilitation will support aquatic organism passage such that the bridge inlet and outlet will be approximately at the same level of the surrounding supported stream bed. Dewatering will be required.

2. Detailed information for the East Branch River Loop Road Restoration Project is attached. Attachment 1, Location Map and Specifications, includes a map of the project location, proposed crossing inlet elevations, a partial list of materials and information on water control.

3. Quote Item: Remove/Replace/Restore Road Bridge System with a larger open channel structure on the Penobscot River loop Road.

5.0 Delivery

• The Contractor shall provide all tools, labor, equipment, supervision, transportation, and materials necessary to repair the roads and bridge.

• All work to take place will be within Katahdin Woods and Waters National Monument (KAWW), located in Penobscot County of Northern Maine.

• The contractor will submit shop drawings for the pre-cast concrete bridge sections, steel structure, and the concrete blocks. The bridge sections shall be rated at HS-25, capable of handling standard logging truck weights. The pre-cast concrete deck panels are available from suppliers but can be fabricated by winning bidder. All concrete shall be a minimum of a 6-bag mix and 3000 pounds per square inch strength. The concrete deck panels and steel structure design for HS-25 loading will be designed and stamped by a structural engineer and shall show all reinforcing steel placement.

• Gravel will be crushed to between 0.75 inch and 1.5-inch minus and be well graded so that it can be compacted into a stable road base. No gravel is available on site. Submit gradation analysis.

• The Contractor shall submit a safety plan to the Contracting Officer prior to performing any work under this contract.

• The Contractor shall submit a work schedule and sequence of events to the Contracting Officer prior to performing any work under this contract. There will be a pre-construction meeting held prior to the start of work on-site.

• The contractor shall submit a plan for traffic control or for any road closures. All signs and traffic control shall be the contractor’s responsibility. A total road closure for 96 hours will be allowed. Contractor must give 48 hours prior notice for the closure.

• The contractor will submit a dewatering and watercourse management plan for the bridge work.

• A final inspection must be held with the government upon completion of the work.

• All vehicles and equipment shall be cleaned of any dirt or vegetation, particularly on the undercarriage, tracks, and sprockets before coming to the jobsite.

6.0 Government-Furnished Property

The Government will not be furnishing nor providing any property to the contractor for this contract. Excess excavated material due to the culvert replacement can be deposited within 4 miles of the project. Offsite disposal of the old bridge components and appurtenances will be the contractor’s responsibility.

7.0 Security

Contractor shall be responsible for securing the work site, materials, equipment, and tools during the duration of the contract. If a temporary staging area is required, KAWW may identify and agree to a location with KAWW. The Government will take no responsibility for lost, stolen or damaged property as a result.

8.0 Place of Performance

The contract work shall be performed on the East Branch Penobscot River Loop within Katahdin Woods and Waters National Monument (KAWW), located in Penobscot County, Maine.

9.0 Period of Performance

The onsite work can only be done between the 15th of July and the 30th of September in any calendar year. The period of performance for this contract begins with a notice to proceed and shall end on 30 September 2024.

Period of performance shall be extended into 2025 if time of award is later than August 15th, 2024.

Submittals identified in Section 5.0 shall be provided to the Government within 14 days of award of this contract for review and approval. It is anticipated that the Government will require a minimum of 5 business days to review the submission.

Once the submittals are approved by the NPS, the contractor shall commence work, completing it within the period of performance specified above.

Attachment 1

#7221

Crossing #7221

NPS

3/19/2024 0 5 102.5 mi

0 8 164 km

1:421,788

#7221

Crossing #7221

NPS

3/19/2024 0 0.6 1.20.3 mi

0 1 20.5 km

1:52,723

Site Map - Drainage Area

Site Photos

Inlet Outlet

Upstream Downstream

Outlet Blocked by Beaver Dam

Site Topography - Existing Conditions

Stream Profile - Existing Conditions

Note: This view is vertically exaggerated, reflecting the different scales of units for elevation and distance.

Trail

Existing bridge deck structure

& abutments

Agraded due to backwater from mainstem East

Branch Penobscot

XS1

Cross-Section 1 - Reference Reach Upstream of Crossing

Upstream to Cross-Section Downstream to Cross-Section

Bankfull Width = 19'

Substrate Composition:

XS Area ≈ 32 sq ft

Site Topography - Proposed Conditions

Fill Information:

Permanent Fill = 180 sq. ft.

Temporary Fill = 75 sq. ft.

Stream Profile - Proposed Conditions

Note: This view is vertically exaggerated, reflecting the different scales of units for elevation and distance.

RoadOverall Stream Slope = 0.5%

Proposed 32' Clear Span

Bridge

Existing Stream Bed

Expected Stream Bed

Proposed Bridge - Inlet Elevation

Existing ≈ 18' x 3.5' Opening

45 ft2

Bottom of

Footing 608'

Estimated Capacity 132 ft2

Clear Span = 32'

Bankfull Width = 19'

1% Probability Flow

Road Raised ≈2' over 100'

HW Ratio ≈ 0.69

9" H x 9" W Curbing (attached to deck)

Road Surface at 613'

9 @ 16' L x 4' W x 8" H Concrete Deck Panels

Steel I-Beam Deck Superstructure ≈ 32' L x 15' W x 1.5' H

Bottom of Excavation

603'

2' x 2' x 16' Beam

Seat

2' x 2' x 16' Beam

Seat

Inlet Elevation ≈ 604'

Rock bank armor wraps around ends of footings

16' L x 2' W x 3" Concrete End Dam (both ends)

Proposed Bridge and Abutment Elevation

Bed and Bank Schematic:

Banklines are composed of 12-18 inch (average intermediate dimension – not longest or shortest measure) competent, angular to sub-angular foundation rock. Banklines connect to the natural stream banks on both sides upstream and downstream to improve scour protection and terrestrial organism passage. Additional smaller rock and fines are also necessary for filling gaps in the larger material to provde more stable banklines. Fines must be watered into bank rock to fill voids.

Flow

Plan View

9' Full Excavation

Depth

Inlet Elevation

604'

Outlet Elevatio n 603.9'

Bottom of Footing

Excavation

607.5'

Curb

Bridge/Road Width 16' Road Surface at ≈ 613' Elevation

Stream Banks Stream Banks

Curb

2' x 2' x 16' Block/Beam Seat

8" H Concrete Deck Panels

Road Fill

36' L x 15' W x 1.5' H Steel I-Beam Deck Superstructure

Area of rock armoring to protect bridge footings to below stream grade

Concrete End Dam

16' x 2' x 3"

Hydrology & Hydraulic Analysis

HY-8 Hydraulic Analysis Program of the U.S. Federal Highway Administration provides results for the above peak flow estimates for the proposed crossing design, and indicates that the crossing as proposed will successfully pass the expected 1% probability storm event with additional space to pass flood-borne material (and higher flows).

Attribute Value Units Definition References:

Drainage Area 1.81 sq. miles Area that drains to crossing 99 70

Wetlands 6.7 percent Percentage of NWI storage 50 100

Elevation 920 feet Mean bason elevation 20 158

Precipitation 42 inches Mean annual precipitation 10 202

Aquifer 13 percent 4 261

2 309

X-coordinate 514314 State Plane m Basin centroid E/W location 1 358

Y-coordinate 5107044 State Plane m Basin centroid N/S location 0.2 480

Return

Probability (%)

Peak QT

(ft3/s)1

1 Lombard, P.J., and Hodgkins, G.A.,2020, Estimating flood magnitude and frequency ongaged and ungaged streams in Maine: U.S. Geological Survey Scientific

InvestigationsReport 2020–5092, 56 p.

(https://doi.org/10.3133/sir20205092)Percentage of land underlain by sand & gravel aquifers

Discharge Names

Total Discharge

(cfs)

Headwater Elevation

(ft)

Flow Type

Outlet Depth

(ft)

Outlet Velocity

(ft/s) 99 70.00 605.85 3-M1t 1.75 2.45

50 100.00 606.18 3-M1t 2.02 2.84

20 158.00 606.71 3-M1t 2.47 3.40

10 202.00 607.06 3-M1t 2.76 3.74

4 261.00 607.49 3-M1t 3.12 4.12

2 309.00 607.81 3-M1t 3.38 4.39

1 358.00 608.11 3-M1t 3.64 4.63

0.2 480.00 608.80 3-M1t 4.21 5.14

Water Control:

Material Specifications:

It is critical that water be controlled during construction, maintaining stream flow, and eliminating potential sedimentation and erosion. Fish must be removed and excluded from the work site before in-stream work begins (including properly screening pump intakes). All Maine Department of Environmental Protection Best Management Practices for Sediment and Erosion Control should be followed. Sandbag or other cofferdams should be placed to control stream flow to isolate the work area and maintain water quality during construction while allowing pumping of clean stream water around the site. Abutments can be excavated and installed while the site is isolated, with dirty water from the work zone pumped out and filtered in nearby forest to avoid contamination of the stream. Sufficient pump capacity is essential to maintain water control, with backup pumps on hand or readily available.

32' Clear Span Bridge: * Must meet HS-25 load rating or better Deck Structure: Footing Blocks / Beam Seats: 2 @ 16' L x 2' W x 2' H 5 @ 36' L x 1.5' H I-Beams * connected w/braces for load distribution 9 @ 16' L x 4' W x 8" thick steel-reinforced deck sections with 9" x 9" curb (attached after installation) 2 @ 16' L x 2' W x 3" thick concrete end dams for closing off steel superstructure from road fill

Footing Bed: 2-3 yds 3/4" crushed stone

Rock for scour protection and bed features: 40 yds @ 12-18" & 6 yds 6"-minus gravel

Road Fill to raise bridge elevation 2' (12" over deck) 90 yards

Sandbags for Cofferdams: 12 large (1-ton)

Polyethylene Sheeting (6 mil - for cofferdam sealing as needed) ) 400 sq. ft

Pump conveys streamflow during construction

Removal of existing culvert/bridge Dirty water pumped from work site Dirty water filtered in nearby forest

Water Control: Cofferdam, Pump & Filtration Placement

Cofferdam

Block Net

Block Net

Dirty Water Pump

Clean Water Pump

Cofferdam

Filtration Basins