B08-Attachment_1-SOW_Kelloch_Moutain_Road_Culvert_7542.pdf

STATEMENT OF WORK (SOW)

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

County, Maine PMIS KAWW 333899A- Culvert Restoration East Branch Mud Brook Tributary

Kelloch Mountain Road T2-R8 WELS #7542

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 culvert system with an open channel arch system within KAWW to facilitate Atlantic Salmon passage. Crossing #7542 consists of an existing culvert which is presenting a barrier to aquatic organism passage to the headwaters of Mud Brook.

2.0 Scope

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

The proposed arch will have an open area (capacity) of about 20 square feet, as compared with the current culvert at less than 5 square feet. The arch will offer a clear span between abutments of 7.25', or over 1.4 times bankfull width. This width is appropriate for providing additional capacity with a relatively low and limiting road height. The abutments of the proposed arch will consist of two courses of concrete blocks with their base set below the level of potential scour. The new crossing will contain banks inside that connect to and match existing stream banks, which will consist of 12" - 24" rock to protect the abutments and filled in/mixed with a 6"-minus mixture to fill voids in the larger rock and create banks passable by terrestrial animals. The arch will be covered by ≈ 1' of gravel fill, with a new road elevation of 772', or approximately

1' higher than current road elevation, which will require the addition of approximately 80 yards of fill.

3.0 Objectives

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

4.0 Tasks

Tasks include:

• Remove one existing culvert system 20 ft. in length.

• Install rebuilt open channel arched culvert structure.

Repair / Replace Culvert: Culvert is on the Kelloch Mountain Road one half of a mile from the Katahdin Loop Road T2-R8 WELS in Penobscot County – See Attachment 1, Location Map and Specifications.

1. Culvert - Remove and replace road culvert work includes, but is not limited to, removal of damaged concrete and metal 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 culvert approach work. Culvert replacement and rehabilitation will support aquatic organism passage such that the culvert 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 Mud Brook Tributary at Kelloch Mountain 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 Culvert System with a larger open channel structure the Kelloch Mountain Road.

5.0 Delivery

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

• 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 culvert sections, and the concrete blocks. The bridge sections shall be rated at HS-25, capable of handling standard logging truck weights. The pre-cast concrete arch 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 arch 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 72 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 Kelloch Mountain Road Road 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

# 7542

Crossing #7542

NPS

3/19/2024 0 5 102.5 mi

0 8 164 km

1:421,788

#7542

Crossing #7542

NPS

3/19/2024 0 1 20.5 mi

0 2 41 km

1:105,447

Site Map - Drainage Area

Site Photos

Inlet Outlet

Upstream Downstream

Site Topography - Existing Conditions

Stream Profile - Existing Conditions

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

Road Elevation

771'

Existing

2.5' CMP

Beaver Dam Upstream

XS1Boulder

Likely Agraded by past beaver impoundment downstream

Cross-Section 1 - Reference Reach Downstream of Crossing

Upstream from Cross-Section 1 Downstream from Cross-Section 1

Bankfull Width = 5' Substrate Distribution:

Primary substrate is sand, with very small amount of cobble in one location -no distribution taken

XS Area = 13 sq ft

Site Topography - Proposed Conditions

Stream Profile - Proposed Conditions

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

Overall Stream Slope 1.8% Road Elevation Raised to 772'

Proposed Concrete Arch on

Concrete Block Abutments

Stream Bed to Degrade

Stream Bed to be regraded during construction

Proposed Arch - Inlet Elevation

Existing

2.5' CMP

4.9 ft2

Road Surface at 772' Elevation - Raised ≈ 1' to increase capacity

Bottom of Abutment

Blocks 764.75'

Inlet Elevation

766.5'

Estimated Capacity

20 ft2

Abutment Blocks of varying lengths

7.25' Inside Abutment Width 5' Bankfull Width

1% Probability Flow

≈ 1' of Gravel Fill Over Arch

HW Ratio = 0.69

Proposed Arch and Abutment Elevation

Note: Abutment block and arch seams must not match; there should always be overlap to increase stability.

Bed and Bank Schematic:

Inlet Elevation

766.5'

6.75' Full Excavation

Depth

Outlet Elevation

766'

Bottom of Excavation

764.25'

Road = 20' Arch = 24' Abutments = 26'-28'

2' x 2' x 12' Block 2' x 2' x 12' Block2' x 2' x 4' Block

1' x 2' x 8' Block 1' x 2' x 10' Block 1' x 2' x 8' Block

10.5' x 4.5' x 4' Arch Sections

Banklines are composed of 12-24 inch (average intermediate dimension – not longest or shortest measure) competent, angular to sub-angular rock.

Banklines must connect to the natural stream banks on both sides upstream and downstream to improve scour protection and terrestrial organism passage. Additional smaller rock and fine material is also necessary for filling voids in the larger material to provde more stable banklines. Fines should be watered into banks to fill voids, and to avoid stream flow percolating into bed and banks.

Flow

Plan View

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 flow event with at least 20% free headspace.

Attribute Value Units Definition References:

Drainage Area 0.23 sq. miles Area that drains to crossing 99 5

Wetlands 5 percent Percentage of NWI storage 50 18

Elevation 864 feet Mean bason elevation 20 30

Precipitation 43 inches Mean annual precipitation 10 39

Aquifer 16.6 percent 4 52

2 63

X-coordinate 523377 State Plane m Basin centroid E/W location 1 75

Y-coordinate 5075813 State Plane m Basin centroid N/S location 0.2 106

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 5.00 767.12 1-S2n 0.42 3.45

50 18.00 767.67 1-S2n 0.81 4.89

20 30.00 768.03 1-S2n 1.00 5.90

10 39.00 768.26 1-S2n 1.12 6.51

4 52.00 768.59 1-S2n 1.29 7.21

2 63.00 768.91 1-S2n 1.42 7.73

1 75.00 769.27 1-S2n 1.55 8.23

0.2 106.00 770.13 1-S2n 1.88 9.28

Water Control:

Material Specifications:

It is critical that water be controlled during construction, allowing free flow of the stream through the site, 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 cofferdams must be placed to enable pumping of stream flow during during removal of the old pipe and throughout construction to isolate the work area and maintain water quality. Any dirty water must be pumped from the site and filtered in nearby forest.

Abutments can be excavated and installed, and banks can be built while the site is relatively dry. Sufficient pump capacity is essential to maintain water control, with backup pumps on hand or readily available. When the new structure is completed, cofferdams can be removed, routing stream flow through the new crossing.

Concrete Arch capable of carrying HS-25 loads 6 @ 10.5' x 3.5' x 4' arch sections Abutments Blocks: (Dirigo Timberlands or similar) 4 @ 1' H x 2' W x 5' L w/groove 4 @ 2' H x 2' W x 8' L w/groove 2 @ 2' H x 2' W x 4' 4 @ 2' H x 2' W x 12' L

Crushed Stone for abutment bed: 4 yds 3/4" stone

Rock for scour protection and bank armoring: 12 yds @ 12-24" & 4 yds 6"-minus gravel

Road Fill to raise road elevation 1' for 100' 80 yards

Sandbags for Cofferdams: 40 small (60 lb.)

Polyethylene Sheeting (6 mil - for cofferdam sealing as needed)

Cofferdam controls water for pumping Removal of existing culvert Dirty water pumped from work site Dirty water filtered in nearby forest

Water Control: Cofferdam, Pump & Filtration Placement

Cofferdam

Cofferdam

Block Net

Block Net

Clean Water Pump

Dirty Water Pump

Filtration Basin

Clean Water

Pump

Dirty Water Pump

Fill Information:

Permanent Fill = 120 sq. ft.

Temporary Fill = 50 sq. ft.