Proposal for Read Farm Lane / Brookside Drive Flood Study ...dorsetvt.org/.../stone_enviro_proposal_12-9-19.pdf · 12/9/2019 · wetland and floodplain complex, and the interplay

PROJECT NO.

P19-165 REVIEWED BY:

MRA

PREPARED FOR:

Rob Gaiotti / Town Manager Town of Dorset, Vermont PO Box 715 East Dorset, VT 05253 [email protected] 802.362.4571

SUBMITTED BY:

Gabe Bolin, PE / Senior Water Resources Engineer Stone Environmental, Inc. 535 Stone Cutters Way Montpelier / VT 05602 [email protected] 603.809.6101

Proposal for Read Farm Lane / Brookside Drive Flood Study & Preliminary Engineering Services Dorset, Vermont

December 9, 2019 Rob Gaiotti, Town Manager Town of Dorset, Vermont PO Box 715 East Dorset, VT 05253 802-362-4571 x3 [email protected]

Stone Project No. P19-165

Subject: Response to RFP– Read Farm Lane / Brookside Drive Flood Study & Preliminary Engineering

Services

Dear Rob and Members of the Selection Committee:

Stone Environmental (Stone) is excited to submit this proposal to the Town of Dorset (Town) to

complete a flood study and preliminary flood mitigation engineering designs for the Read Farm Lane

and Brookside Drive area of Dorset, Vermont, in the vicinity of Vermont Route 7A.

Stone has thoroughly reviewed the Request for Proposals (RFP), visited the project area and reviewed

related documents in preparation of this proposal. We believe our approach to the Scope of Services

provides a comprehensive assessment of existing natural resources, including the Batten Kill River, the

wetland and floodplain complex, and the interplay between these environmental systems during various

flood conditions. A thorough characterization of existing infrastructure, primarily the Batten Kill River

crossings at Route 7A and Railroad Bridge 76 will also be essential. This data will be obtained during

field work and detailed in the 2-dimensional hydraulic model, providing a solid foundation for the

evaluation of flooding under design storm events, and a robust analysis of flood mitigation alternatives.

We propose to use the US Army Corps of Engineers HEC-RAS model, which Stone staff have used for

analysis and design purposes on over 24 river and stream projects since 2012, with 16 of those projects

being constructed to directly address flooding and infrastructure vulnerability issues.

The bulk of Stone’s stream restoration experience is grounded in the development and comparison of

restoration alternatives, followed by the design and construction of the selected alternative. The

development of appropriate and cost-effective restoration alternatives is the common thread that runs

through our culvert upgrade, dam removal, bank stabilization and flood mitigation projects. Stone

typically works with stakeholders during alternative development, and evaluates those alternatives via

modeling, engineering calculations and benefit-cost analyses. Stone is well-versed in working with

stakeholders and in public settings in facilitating the selection of a final alternative. We also regularly

assist our municipal and NGO clients to assess, evaluate and pursue appropriate grant funding.

We believe we are uniquely qualified to support the Town, the Bennington County Regional

Commission and other stakeholders in assessing existing flooding conditions and developing feasible,

cost-effective mitigation alternatives that will address these flooding issues over the long-term. In

addition to our project experience and technical capabilities, Stone’s engineers have designed and

implemented river restoration projects in both Dorset and neighboring towns, with the primary goal of

replacing vulnerable infrastructure and increasing flood resiliency over the long-term. Having designed

and managed the construction of road-stream crossing upgrades along the Mettawee River at Tower

Road (concrete bridge) and Pastures Lane (steel stringer bridge) in 2017, and an AOP passage retrofit

project at the Mettawee River and Lower Hollow Road (sequenced rock steps) in 2016, I’m very familiar

with the Town of Dorset’s natural resources and existing infrastructure.

Additionally, prior to my work in town, in 2014 I worked with the Forest Service and designed a road-

stream crossing upgrade along Forest Road 58 at Mad Tom Brook in Peru, VT, in response to nearly

$300,000 of road damage after the brook overtopped the existing culvert, breached the road embankment

and caused significant erosion during Hurricane Irene in 2011.

Stone has the expertise and experience to be valuable partners to the Town and stakeholders on this flood

evaluation and mitigation design project. We appreciate this opportunity to share our ideas with you and

are available to answer any questions you may have regarding our proposal.

Sincerely,

Gabe Bolin, PE Senior Water Resources Engineer Direct Phone / 603.809.6101 Email / [email protected]

Town of Dorset, Vermont / December 9, 2019 Read Farm Lane/Brookside Drive Flood Study & Prelim. Eng. Services ©2019 Stone Environmental. All rights reserved

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Proposal for Read Farm Lane / Brookside Drive Flood Study & Preliminary Engineering Services

Contents

Primary Point of Contact .............................................................................................................. v Individuals Involved with Bid Preparation ................................................................................... v 1. Qualifications and Experience ............................................................................................... 1

1.1. Firm Qualifications ......................................................................................................... 1 1.2. Key Personnel Roles and Bios ......................................................................................... 1 1.3. Relevant Project Experience ........................................................................................... 4

Allen Brook Watershed, Large Culvert Assessment and Replacement Prioritization Study, Williston, Vermont (2018-2019) ........................................................................ 4 Pine Mill Dam Removal, Haverhill, New Hampshire (2018-2019) .................................. 5 Stevens River Bank Stabilization, Barnet, Vermont (2017-2019) ................................... 6 Seaver Brook Road-Stream Crossing Upgrade, Plaistow, New Hampshire (2018-2019) 8 Chestnut Hill Stormwater Mitigation Design, Montpelier, Vermont (2018-2019) ......... 8

2. Scope of Work ....................................................................................................................... 9 2.1. Project Understanding ................................................................................................... 9 2.2. Initial Site Visit ............................................................................................................. 10 2.3. Detailed Scope of Work ............................................................................................... 11

Task 1: Meetings and Project Management ................................................................ 11 Task 2-1: Field Work – Topographic Survey ................................................................ 12 Task 2-2: Field Work – Geomorphic Assessment ......................................................... 12 Task 3-1: Alternatives Modeling – Hydrology .............................................................. 13 Task 3-2: Alternatives Modeling – 2-D Hydraulic Model .............................................. 13 Task 4: Alternatives Analysis & Report ........................................................................ 15 Task 5: Conceptual Design Plans & Costs .................................................................... 15 Task 6: Conceptual Design Report or Memo ............................................................... 16 Task 7: Project Meeting .............................................................................................. 16

3. Project Tasks, Deliverables and Schedule ............................................................................ 17 4. Costs .................................................................................................................................... 19

List of Tables

Table 1. Summary of Meetings ....................................................................................................... 11 Table 2. Project Tasks, Deliverables and Schedule ........................................................................... 17 Table 3. Cost Table ......................................................................................................................... 19

Cover Photo: Looking west towards the Route 7A bridge from the railroad bridge, along the Batten Kill River in Dorset, VT


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Primary Point of Contact Gabe Bolin, PE, will serve as the single point of contact. He can be reached via email ([email protected]) or phone (cell: 603.809.6101).

Individuals Involved with Bid Preparation The following staff contributed to the development of this bid proposal: Gabe Bolin, PE (Single POC & Drafter) and Carleigh Rixon (Drafter), Meghan Arpino (Drafter & Reviewer).


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1. Qualifications and Experience

The following sections provide our qualifications, including team member roles and bios, areas of expertise, and experience with similar projects. Note that resumes for staff listed in this section are provided in the link provided in Section 1.3 below.

1.1. Firm Qualifications Stone Environmental is a small, 100% employee-owned company based in Montpelier, Vermont that provides scientific tools, information, and analyses to help clients solve environmental challenges with integrity, expertise, and innovation. Our areas of expertise include stream and ecological restoration design and implementation, flood analysis, AOP and geomorphic assessments, hydrology and water quality modeling, hydraulic modeling, stormwater planning and design, environmental monitoring, and geospatial analysis, visualization, and application development.

The work of Stone’s Water Resources scientists and engineers is focused on understanding and addressing the effects of land use on Vermont’s water resources though field investigation, computer modeling, GIS spatial analysis, and project design and implementation. We apply defensible scientific methodologies, effective project design, and efficient implementation strategies to improve water quality, reconnect aquatic habitats, protect environmentally sensitive areas, increase flood resilience and reduce infrastructure vulnerability. Our stream restoration experience includes culvert surveys; culvert assessments for hydraulic compatibility, geomorphic compatibility, and aquatic organism passage (AOP); flood analysis and mitigation design; and the design and construction oversight of dam removals, culvert upgrades, streambank and channel restoration projects. Our restoration designs strive to balance the restoration of AOP, sediment transport, and other geomorphic functions with the long-term protection of infrastructure within the built environment.

The following sections provide the qualifications and experience of our key project staff, as well as a selection of relevant project examples to demonstrate our experience with flood assessments and stream restoration and infrastructure improvement projects. Resumes of personnel are provided in Appendix A.

1.2. Key Personnel Roles and Bios

GABE BOLIN, PE Senior Water Resources Engineer Project Manager, Primary Point of Contact, Lead Engineer

Gabe will serve as the project manager and primary point of contact for the Town and stakeholders, as well as the lead engineer for field work, modeling, alternatives evaluation and design. Gabe is a licensed Vermont Professional Engineer with over 20 years’ experience in stream restoration and flood resiliency design and implementation. At Stone, Gabe utilizes his knowledge of these disciplines to develop solutions that restore natural conditions and reestablish ecosystem balance, while protecting existing infrastructure. He is a hands-on engineer with extensive experience performing topographic and fluvial


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geomorphic surveys, characterizing existing infrastructure, evaluating environmental and regulatory impacts, creating design plans, and managing construction projects. Gabe is currently leading a variety of stream restoration design projects, including three dam removals, four culvert upgrades and a bank stabilization project. Gabe earned a BS in Bioenvironmental Engineering from Rutgers College and a ME in Coastal Engineering from Stevens Institute of Technology.

Before joining Stone in 2017, Gabe was the Eastern Regional Stream Engineer for Trout Unlimited, where he assisted the US Forest Service (USFS) with a watershed-scale restoration project along the Mettawee River in Dorset. During his work on that project, Gabe, along with a structural engineering partner, designed and oversaw construction of the concrete bridge at Tower Road and the steel stringer bridge at Pastures Lane in 2017, and the rock-step retrofit project at Lower Hollow Road in 2016. Gabe also wrote a number of grant applications to acquire over $50,000 in funding for those projects. Prior to his work on the Mettawee River, in 2014 Gabe assisted the USFS with the design of a road-stream crossing upgrade on Mad Tom Brook and Forest Road 58 in Peru, Vermont, in response to considerable flood damage following Hurricane Irene in 2011.

PETER LAZORCHAK, PE, LEED AP Senior Water Resources Engineer Engineering Support, Quality Assurance/Quality Control Review

Peter will provide senior engineering support and review of all engineering deliverables. During reviews, Peter will review model inputs/outputs, check calculations, review plans for completeness and ensure deliverables are at a level of quality appropriate for the intended submittal. Peter has over 20 years’ experience in the consulting industry with a diverse background in hydrology, hydraulics, environmental services, civil engineering, and construction oversight. His areas of expertise include stormwater management, water resources engineering, on-site wastewater disposal, site development, and navigating the local, state, and federal permitting processes. Peter strives to provide solutions to his clients that balance natural resource protection with the built landscape by utilizing low impact development (LID) techniques and designing green infrastructure. He is a licensed Professional Engineer in Vermont, a Vermont Class B Licensed Designer, and a LEED Accredited Professional.

MEGHAN ARPINO Hydrologist Engineering Support, Lead Modeler

Meghan will assist with all tasks including field work and surveys, reporting and benefit-cost analysis, and will serve as the task lead of the hydrology and hydraulics modeling effort. Meghan has an extensive background in the environmental field with specific expertise in surface water hydrology. She has worked on projects throughout the United States, and is experienced in water-quality sampling, stream habitat assessments, geomorphic assessments, topographic and fluvial surveying, statistical hydrology and hydraulic modeling. Meghan is currently supporting three dam removal and two culvert upgrade projects. Most recently, she performed a geomorphic assessment and conducted hydrology and hydraulic modeling to evaluate dam removal scenarios for the Pelletier Dam in Castleton, Vermont.

Prior to joining Stone, Meghan assessed stream crossings for geomorphic compatibility, condition, and AOP passage as part of the Rockingham Planning Commission’s Regional Stream Crossing Assessment project. As part of her master’s research, Meghan focused on understanding the influence of hydraulics on reach-scale fluvial nutrient uptake, an important ecosystem service and the focus of many stream restoration projects. Meghan developed a 2D numerical hydraulic model for an approximately 4.5 km reach of the Suncook River in Epsom, NH using high-resolution LiDAR bathymetry and the Delft3D-


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Flow and Delft3D-Water Quality modules developed by Deltares. The 2D model output was validated using non-toxic dye releases to validate solute transport, as well as water surface elevation and velocity point measurements. Simulations were run for both steady and unsteady (storm event) flows. The hydraulic model was used to estimate flow depth, velocity, and shear stress through the study reach. Model results were also used to determine nitrate transport characteristics and assess floodplain inundation at low to moderate flows. Meghan holds a B.S. in Environmental Science from the University of Vermont, and an M.S. in Hydrology from the University of New Hampshire.

BRANDEN MARTIN, EI Water Resources Engineer Engineering Support, Lead Surveyor

Branden will assist with all engineering design tasks including development of the 30% design plans and specifications, and all benefit-costs analyses. Branden will also serve as the task lead for the topographic surveying and infrastructure characterization effort. Branden has over 5 years of experience working on stormwater infrastructure, stream and bank restoration projects. Branden is fully versed in topographic surveying using total stations and data collectors, has collected a variety of data to support H&H models in various natural and urban settings, and is highly proficient in using AutoCAD to develop engineering plans and generating quantities for cost estimating purposes. Branden is currently working on two dam removal projects and a stormwater retrofit project that will reduce flow impacts to a nearby brook. Branden received a B.S. in Civil Engineering from the University of Vermont.

JODY STRYKER, PH.D. Senior Environmental Modeler Modeling Support, Quality Assurance/Quality Control Review

Jody will provide expert support for hydraulic model, and will provide in-depth review of all model components, including model setup and geometry for existing and proposed conditions, flow boundary conditions files, output warnings and errors, and assist in evaluating output results. Jody has over 10 years of experience in development and application of hydrology and hydraulic models. She has worked extensively with distributed watershed scale models as well as 2-D models at various scales including point, reach, and watershed. As part of her PhD research at the University of Vermont (UVM), she fully coupled a point-based bank erosion algorithm (the Bank Stability and Toe Erosion Model, BSTEM) into a fully distributed mechanistic watershed model (the Distributed Hydrology Soil Vegetation Model). This coupled model was applied to the Mad River watershed in Vermont and used to examine sediment transport processes including assessment of the relative contributions of sediment sources (overland, road, and bank erosion), under both current and future climate scenarios that included more extreme precipitation events. Her academic work also included development of 2-D HEC-RAS models (both steady and unsteady) for evaluating the potential impacts of extreme events in Vermont reaches. She also assisted interns in developing HEC-RAS models that incorporated BSTEM to validate bank erosion at specific locations in association with larger scale modeling of the Mad River watershed. At Stone Environmental, Jody has applied a variety of regulatory and non-regulatory surface and groundwater models to address water quality issues. She has a strong understanding of the scientific principles governing flow, sediment transport, and erosion processing and proven expertise in hydrology, hydraulic, and water quality modeling.


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1.3. Relevant Project Experience The following provides a brief description of relevant projects that are similar in nature to the project scope of work. For each project a ‘Relevant Experience’ box is provided, which lists experience categories that are relevant to this particular flood study and conceptual engineering project. Where each project example fulfills an experience category, a check is provided.

For reference, we’ve provided additional information for each project in the link below. Information includes design plans, H&H modeling reports, a flood no-rise certification, and before and after construction photos. Individual folders are provided for each project in the link directly below. Note that resumes for the project staff listed in Section 1 above are also provided in the link below, in the resume folder.

https://stoneenvironmentalvt-my.sharepoint.com/:f:/g/personal/gbolin_stone-env_com/Epq7cuGvdPpFsL4TjUOJQ08BVQyd6gQ5-Yl5gsFIarGatg?e=fJbKRk

Allen Brook Watershed, Large Culvert Assessment and Replacement Prioritization Study, Williston, Vermont (2018-2019) Stone worked with the Chittenden County Regional Planning Commission (CCRPC) and the Town of Williston to complete an extensive culvert assessment and prioritization project in the Allen Brook watershed. The primary goal of this project was to assess the condition of all large culverts (greater than five feet in diameter), prioritize their replacement, and develop conceptual designs and costs, such that the Town can include the costs in their Capital Improvement Plan and proactively plan for replacement of the structures.

Stone completed an initial desktop review including drainage area delineation, geomorphic context, expected bankfull width and depth and environmental resources (T&E species, floodplain, wetlands, depth of fill over culvert, fish habitat, etc.). The desktop review was followed by a field assessment performed in accordance with ANR’s Bridge and Culvert Assessment Manual (Vermont Stream Geomorphic Assessment Protocols, 2009). As part of the topographic survey and assessment, Stone documented site conditions at each culvert with photos, measurements and site layout sketches. Additionally, Stone collected data related to structural condition, alignment, scour, perching, ponding, accumulated debris, aquatic organism passage (AOP), bankfull width, and geomorphic conditions.

Relevant Experience Stakeholder/Community Engagement and

Collaboration Topographic Surveying Geomorphic Analysis Infrastructure Characterization and Stability

Assessment Hydrology & Hydraulic (HEC-RAS) Modeling Flooding Assessment Flood Mitigation Design Alternatives Analysis Potential Impact Assessment Benefit-Cost Analysis Development of Design, Specification and

Opinion of Probable Costs

10’ diameter culvert at Old Stage Road and Allen Brook in Williston, VT (Source: Stone Environmental).


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For each of the four sites, Stone calculated and modeled peak flows for a range of design storm events using methods outlined in the 2015 edition of the VTrans Hydraulics Manual. The hydrology and hydraulics (H&H) modeling results were then used to identify and preliminary size long-term culvert replacement options that would match or exceed DEC’s recommended standards to attain full geomorphic capability, accommodate AOP over a range of flows, mitigate flooding and produce acceptable water surface elevations for select design storm events. Stone provided a summary of long-term options, conceptual costs, and anticipated service life for each proposed solution, which included traditional concrete bridges, concrete box culverts, aluminum box culverts, aluminum/steel structural plate arches, steel stringer bridges, and other feasible alternatives. In addition, Stone performed outreach to ANR and District 4 Act 250 officials to ensure that the team had a clear understanding of permits that will be needed or requirements that would impact the proposed road-stream crossing upgrade designs. Stone reviewed replacement options with local, State, and Federal Agencies, and provided a summary of permit requirements to inform the Town.

Stone provided designs and cost estimates to the 30% design level and developed a replacement prioritization that included criteria including structural condition, potential remaining service life, frequency of previous repairs, potential for clogging and/or collection of debris, cost of repair/replacement, environmental impacts, and water quality benefits.

Reference: Sai Sarepalli, PE, Transportation Planning Engineer Chittenden County RPC, 110 West Canal Street, Suite 202, Winooski, VT 05404 Tel.: (802) 861-0134 | Email: [email protected]

Pine Mill Dam Removal, Haverhill, New Hampshire (2018-2019) Stone was hired by the Connecticut River Conservancy to provide design and construction management services for the removal of the Pine Mill Dam along Clark Brook, in the Town of Haverhill, New Hampshire. The 15-foot-high by 180-foot-long concrete gravity dam was constructed c. 1928 to power an adjacent grist mill. The mill was in operation until the 1940s, when electrical power replaced waterpower at the facility around 1941. Since the 1940s the dam was in a deteriorated condition, and over time flows undermined the dam foundation. The dam temporarily impounded water during spring runoff and large storm events, and there was concern that the floodwaters could impact the adjacent building, as the building foundation was still connected to the dam and the building was in poor condition. Despite flows bypassing the structure at times, the dam also proved to be an impediment to fish passage.

Stone collected and reviewed historical data, performed topographic and geomorphic surveys, characterized the dam (i.e. took measurements, probed sediment to determine footing dimensions, assessed structural composition, etc.), performed H&H modeling, and utilized the hydraulic model to conduct an alternatives analysis to determine the most cost-effective structure removal scenario, relative to flood mitigation and improved fish passage. Stone developed design plans using the USFS Stream






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Simulation Methodology (2008), and included measures for the contractor to follow in order to not impact the adjacent building, including saw cutting completely through the dam prior to removal operations. For each removal scenario, potential impacts to the building, fish passage and the proposed channel were evaluated. The scenario that provided a water surface elevation for the 100-year storm event that did not impact the building, and for year-round fish passage was selected.

Stone incorporated a channel restoration plan that included steps, pools, riffles and large wood at dimensions and frequencies similar to those found in reference reaches, to provide for channel stability, dissipation of flow energy and improvements to fish habitat. The channel design also included bank and floodplain areas that were seeded and planted with native vegetation, and reinforced with geotextile fabrics, providing erosion protection to ensure long-term establishment of vegetation. Project construction was completed in September 2019.

Reference: Ron Rhodes, River Steward Connecticut River Conservancy, P.O. Box 94, South Pomfret, VT 05067 Tel.: (413) 768-4994 | Email: [email protected]

Stevens River Bank Stabilization, Barnet, Vermont (2017-2019) Stone was hired by the Connecticut River Conservancy to provide engineering design services for a bank stabilization project along a portion of the Stevens River in Barnet, Vermont. The project area included an incised meander bend that was migrating towards residential property, and also threatening to cut off access to a portion of the property used as horse pasture. Stone performed a geomorphic assessment and concluded that the replacement of approximately 200 feet of stream channel with a concrete culvert associated with the construction of I-91 upstream of the site resulted in a significant reduction in channel roughness and excess energy in the system, which was thought to be the primary cause of accelerated migration of the bend in recent years.



Assessment Hydrology & Hydraulic (HEC-RAS) Modeling Flooding Assessment Flood Mitigation Design

Alternatives Analysis Potential Impact Assessment

Benefit-Cost Analysis Development of Design, Specification and


Aerial view of Pine Mill Dam, looking southeast (left, Source: Stone Environmental); Clark Brook during construction following partial dam removal, looking downstream and southeast (right, Source: Stone Environmental).


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A river corridor permit required that a No-Rise certification be submitted, to document that the proposed work did not raise the 100-year flood water surface elevation. Stone developed a HEC-RAS model that tied into the Base Flood Elevations of the FEMA Flood Insurance Rate Maps for this task. Stone used model output to create a map that provided the flood inundation limits for the pre-project and post-project condition. Model results indicated that the project would not raise the 100-year flood water surface elevation.

The proposed bank stabilization included a large wood structure with over 50 pieces of wood and a toe reinforced with large stone. Channel and floodplain elevations were designed to mimic reference conditions, and the top of the wood structure was set at an elevation such that flood events beyond the 1.6 to 2-year recurrence interval events engaged the floodplain. New floodplain areas were included in the design which actually increased flood storage compared to the existing condition. Erosion prevention measures, such as securing erosion control fabric and planting native shrubs, were completed within the limits of the new floodplain. The large wood structure was designed to resist buoyancy, momentum, and drag forces associated with large flood events, as evaluated through hydraulic modeling.

Reference: Ron Rhodes, River Steward Connecticut River Conservancy, P.O. Box 94, South Pomfret, VT 05067 Tel.: (413) 768-4994 | Email: [email protected]

Eroding bank along meander bend of Stevens River adjacent to private property and horse farm (left, Source: Stone Environmental); same meander bend following construction of bank stabilization measures (right, Source: Stone Environmental).


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Seaver Brook Road-Stream Crossing Upgrade, Plaistow, New Hampshire (2018-2019) The Seaver Brook culvert at Pollard Road is undersized and has caused road flooding multiple times in the last few years; it is currently listed in the towns hazard mitigation plan as a priority for replacement. As a sub-consultant to Normandeau Associates, Stone developed a hydraulic model to evaluate a number of replacement structures. The model was also used to ensure that the selected structure provided enough conveyance for flood flows from the wide and well-established floodplains. The design included estimates of flood inundation, an alternatives and benefit-cost analysis, and development of 100% design plans and cost estimates to support contractor bidding.

Reference: Lee Carbonneau, Senior Principal Scientist Normandeau Associates, Inc., 25 Nashua Road, Bedford, NH 03110 Tel.: (603) 637-1150 | Email: [email protected]

Chestnut Hill Stormwater Mitigation Design, Montpelier, Vermont (2018-2019) An unnamed stream channel tributary to Blanchard Brook has widened from approximately 4’ to 12’ over the last 10 years, according to landowners. An undersized culvert, dated stormwater infrastructure and observed increases in stream baseflow are thought to be the cause of frequent flooding along residential properties and within the road during large storm events. Stone was hired by the City of Montpelier to inventory and characterize the existing infrastructure, investigate opportunities for installation of green stormwater infrastructure and stormwater BMPs to reduce stormwater runoff, and to develop a design for properly sized stormwater infrastructure and stabilization of the stream channel. Stone developed 100% designs and costs that included elements which resulted in elimination of flooding in residential properties and in the roadway up to the 100-year storm event. Channel stabilization included a series of steps and pools to help dissipate energy and reduce the risk of erosion.

Reference: Zach Blodgett, Operations Manager/City Engineer City of Montpelier, 39 Main Street, Montpelier, VT 05602 Tel.: (802) 223-9508 | Email: [email protected]


Collaboration Topographic Surveying

Geomorphic Analysis Infrastructure Characterization and Stability




Collaboration Topographic Surveying

Geomorphic Analysis Infrastructure Characterization and Stability

Assessment Hydrology & Hydraulic (HEC-RAS) Modeling Flooding Assessment

Flood Mitigation Design Alternatives Analysis Potential Impact Assessment Benefit-Cost Analysis Development of Design, Specification and



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2. Scope of Work

2.1. Project Understanding The area around Brookside Drive and Read Farm Lane, in the southeastern portion of Dorset, VT experiences frequent flooding. Per the RFP, in the past 12 months flooding has restricted access to five homes on Brookside Drive and caused temporary access issues at nearly 20 homes along Read Farm Lane. A nearby commercial property has also sustained flood damage three times in that time period.

The main branch of the Batten Kill River flows north to south through Dorset and joins the Mad Tom Brook near Village Street and Route 7, approximately 1 mile north of the project. Within the project vicinity, the Batten Kill River crosses under Route 7A via a bridge, and approximately 200’ downstream from that bridge encounters Railroad Bridge 76. Downstream and east of these structures is a large Class II wetland and floodplain complex with significant storage and flood mitigation potential, however as discussed below, these structures are flow impediments and cause a backup of flow during storm events (upstream of both bridges), preventing and/or delaying flow to the wetland and floodplains, leading to river overbank flows and flooding upstream at the roads and commercial property listed above.

As explained in the RFP, residents have partners with the Town, Bennington County Regional Commission staff and Vermont Agency of Natural Resources staff to pursue the primary goal of this project, which is to develop short- and long-term solutions to eliminate and/or mitigate flood frequency and extents within the project vicinity. In-line with that goal, our interpretation of the Scope of Work in the RFP produces the following tasks:

1. Host a project kickoff meeting, and additional meetings throughout the project with the Town and stakeholders to facilitate communication, collaboration, project updates and sharing of data and information.

2. Conduct field work to collection topographic data, characterize existing infrastructure and review natural resource and geomorphic information to gain a complete understanding of the interplay between the river, wetlands and floodplains, and flow hindrances caused by existing infrastructure.

3. Build a robust hydrologic and 2-dimensional (2-D) hydraulic model of the site tied into existing FEMA FIRM elevations, and modify the model to evaluate four alternatives outlined by the Town and stakeholders, plus additional alternatives developed by the consultant.

4. Develop an Alternatives Analysis Report summarizing the results of the analysis, for stakeholder review and alternative selection; include an evaluation of impacts on lands, natural resources and infrastructure and identify any needs for land protection or conservation, that would increase flood storage. In this report a FEMA-based Benefit-Cost Analysis will also be performed to facilitate application of FEMA funds in the future.

5. Develop 30% design plans, specifications and opinion of probable construction costs for the selected alternative, which will most likely include design modifications to the Route 7A bridge


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and Railroad Bridge 76, and potentially include additional measures. A list of potential funding sources will also be included in this step.

6. Prepare a final report to be shared with the Town and stakeholders and make a final public presentation sharing the final design, costs, model results and other deliverables with the audience.

The following provides a brief summary of our field visit associated with the development of this Proposal. A detailed discussion of how tasks will be executed follows that summary.

2.2. Initial Site Visit On November 15, 2019, Gabe Bolin of Stone visited the project in the vicinity of the Route 7A bridge, Railroad Bridge 76 and the Chantecleer Restaurant. Inspections were limited to visual observations and rough measurements. Although further assessment is required, it was observed that the width of the Route 7A bridge seemed moderately undersized, yet the lower chord of the bridge was observed to be very close to the dry weather water surface (~2-3’), and it seemed as if adequate conveyance beyond small storm events would be limited. The lower chord elevation also seemed similar to the elevation of the Batten Kill River top of bank, and therefore we expect that any storm event at or beyond the 2-year recurrence interval storm event may not have adequate conveyance capacity, thereby creating a slowdown of water and backwater effects upstream of the bridge (i.e. leading to potential flooding upstream).

The situation and conveyance capacity at Railroad Bridge 76, approximately 200’ downstream of the Route 7A bridge was observed to be worse. During our site visit, the lower chord of the bridge was actually at the water surface elevation, indicating a complete blockage of flows beyond dry weather conditions. Looking through the water, there was significant scour at the riverbed just downstream of the bridge, indicating severe constriction scour. The railroad, which runs north-south through the entire length of the wetland/floodplain complex, is assumed to be at a flat elevation. Although that elevation is unknown at this time and will be confirmed during surveys, the railroad was observed to be at an elevation above the river top of bank, indicating a significant conveyance blockage beyond the 2-year recurrence interval storm event not only at the river, but along the entire length of the wetland/floodplain complex. From these observations, and the anticipated age of the existing infrastructure, it is assumed that flooding has been occurring in this part of town for quite some time.

In the fields of hydrology and stream restoration, in a healthy stream or river system that is well connected to adjacent floodplains, it is common that river flow begins to engage the floodplains between the 1.6- to 2-year recurrence interval storm events. The flow associated with this storm is commonly referred to as the ‘channel forming flow’, since flows that reach the top of banks, just before they spill into the floodplains are large, concentrated and have maximum shear and erosional force. Engagement of the floodplain leads to a ‘flow relief’ as the flows expand onto the floodplains and velocity and shear forces are significantly reduced. Understanding that the equivalent to the 1.6- to 2-year recurrence interval storm event happens almost every spring when rain-on-snow conditions occur, it is understandable that this area of Dorset floods frequently. And equally significant, the blockage of a river system from the dry weather water surface up beyond the top of banks is a severe geomorphic impediment, indicating that the infrastructure causing the blockage is significantly vulnerable to damage and/or failure on nearly an annual basis, and that impacts to the wetland/floodplain complex ecosystem may be significant.


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2.3. Detailed Scope of Work Task 1: Meetings and Project Management Stone proposes the project meetings summarized in Table 1, which includes five total meetings with the Town and stakeholders per suggestions in the RFP. It was assumed that the Selectboard meeting and the final public presentation were not included in the five meetings. The meetings listed in Table 1 have also been incorporated into the Project Tasks, Deliverables and Schedule Table (Table 2) presented in Section 3 below.

Table 1. Summary of Meetings

Meeting Purpose/Description Approximate Date

Meeting 1: Initial Meeting With Partners & Site Visit

Meet with stakeholders and landowners to relay project initiation, explain scope and schedule and gather additional information. Goals and objectives of the project will be defined.

January 29, 2020

Meeting 2: Optional Potentially meet to discuss field data level of completeness prior to kickoff of the modeling task.

April 15, 2020

Meeting 3: Optional Potentially meet to discuss model results prior to starting the alternatives analysis report.

May 20, 2020

Meeting 4: Modeling and Alternatives Analysis Meeting

Meet with stakeholders and landowners to discuss the Alternatives Analysis, model results and final set of alternatives. Following this meeting, the Town and stakeholders will receive the final set of alternatives to review and select from.

June 3, 2020

Meeting 5: Optional An opportunity to meet sometime during the design phase, to make sure work deliverables are on track with expectations.

July 22, 2020

Meeting 6: Selectboard Meeting Meet with the Selectboard to discuss the final plan and report. Receive Selectboard input prior to the final public presentation.

August 5, 2020

Stone assumes that the timing and purpose of any of these meetings can be altered according to the discretion of the Town and stakeholders.

Approximately 20 hours of project management has been included in this task for the Stone project manager to coordinate internally with staff on project tasks, coordinate in general externally with the Town and stakeholders, and to manage the project budget.

Key Milestones & Deliverables Any required coordination to facilitate or host each meeting. Summary of meeting notes collected by Stone staff and any documentation shared, distributed to

the Town and stakeholders as requested.


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Task 2-1: Field Work – Topographic Survey Due to the anticipated extents of the project area and considering the data accuracy needs with respect to the goals of the project, Stone will mobilize a team to survey the project area using both a total station and a GPS rover. A total station will be used to set control points throughout the project and to survey the dimensions of the Route 7A and railroad bridges, relevant buildings, and other relevant infrastructure. A GPS rover and base station will be used to collect channel profile and cross section data of the Batten Kill River, and collect elevation data throughout the floodplains, roadways, railroad, easements, drainage channels, etc.

Stone will begin the survey by establishing control points throughout the site to provide for horizontal and vertical control. We will attempt to place control points at permanent or well-established structures, or natural features (i.e. large boulders, bedrock, mature trees) so that their integrity will be maintained through both design and construction. When these features are not available, 2-4’ sections of steel rebar will be driven into the ground (and out of the way of car or pedestrian traffic) to refusal and fitted with a protective cap. All control points will be flagged and marked for ease of future location. For quality control purposes, throughout and at the end of the survey, Stone will regularly check back to the survey back sight or control point to assess equipment precision and data accuracy. Any discrepancies found to be over 0.1 feet will result in resurveying of relevant data.

After establishing control points, Stone will perform the survey, collecting elevations along the river (i.e. top of bank, bottom of bank, thalweg, etc.); in the floodplains, including grade breaks; roadway centerline, pavement edge and shots to define the road embankment slope; railroad top width and embankments; corners and elevations of buildings within the floodplain; driveways; high water marks on structures; ground depressions and microtopography; existing infrastructure such as manholes, hydrants and telephone poles; stormwater infrastructure and ditches, and other pertinent information required to fully define the site. Additional measurements collected without survey equipment will include length, width and height of bridge conveyance areas; vertical distance from bridge bottom chords to top of road; sketches and measurements of bridge wingwall configuration; structural condition; water surface elevation during the time of survey; debris accumulation; nature and extent of floodplain surfaces and roughness; and other relevant data. Photos of relevant infrastructure and natural features will be obtained.

Key Milestones & Deliverables Topographic survey of existing conditions (in plan form and an electronic data file). Data and information gathered of existing infrastructure via manual measurement (photocopies and

photos). Survey and infrastructure data will be summarized and provided in the final report.

Task 2-2: Field Work – Geomorphic Assessment Stone will conduct a simple geomorphic assessment, for the purposes of acquiring data required for the hydraulic model. The initial desktop effort will include a drainage area delineation, assessment of geomorphic context (i.e. landscape setting; this project is in the ‘valley’ rather than in steeper headwater reaches), expected bankfull width and depth of the river (based on the Vermont Regional Hydraulic Geometry Curves) and a general characterization of floodplains (valley slope, extent), wetlands (% cover, type), etc. Historical aerials may also be reviewed to help inform the historical rate of planform adjustment and/or encroachment.


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The desktop effort will be followed by a field assessment where Stone staff will wade upstream and downstream of Route 7A to collect basic geomorphic information on the Batten Kill River, identifying bankfull stage (per Appendix K of the Vermont Stream Geomorphic Assessment Handbooks, VTANR, 2004) and measure bankfull widths at regular intervals. Bankfull depth will also be measured at these locations, in addition to flood prone width, such that entrenchment ratios can be calculated. Other features such as bank stability, scour, vegetation, soil type, the degree of river alignment (or skew) with bridges and infrastructure, etc. will be obtained. Photos will be taken at regular intervals. It is anticipated that this initial dataset will be used along with the topographic survey data to build the geometry file of the hydraulic model.

An additional 20 hours of time has been included in this task to cover additional field work, in the event that additional data is needed to support modeling, alternatives analysis or design, or if time is needed to communicate with owners of the railroad regarding access and/or as-built records.

Key Milestones & Deliverables A brief memo summarizing all of the data generated and collected during the assessment. The data will also be incorporated in the final report.

Task 3-1: Alternatives Modeling – Hydrology Stone will develop hydrology for the site by utilizing gage transfer and statistical analysis techniques. Our team will perform a review of USGS stream gages in the area, and download data from gages within a reasonable distance, of similar watershed size, and with similar watershed and geologic conditions. We will process data from the selected gage(s) and develop estimates of peak flow for the 2-, 5-, 10-, 25-, 50-, 100- and 200-year recurrence interval flood events, using the Log-Pearson Type III Distribution flood frequency analysis technique. We will then perform the gage transfer to develop similar peak flow estimates for this site. To create the flood hydrographs that will be required for the unsteady 2-D portions of the model (discussed below), Stone will either 1) use a unit hydrograph approach and the peak flows to create a synthetic flood hydrograph for each storm event, or 2) obtain continuous flow data from USGS gages during known flood events, and perform gage transfers as required.

An additional hydrology analysis will be performed that compares the entire gage record to data collected after 1970, to identify if the hydrology of the site has been impacted by a recent shift in hydrologic regimes as a result of climate change. The most conservative flows will be utilized in the design process.

Key Milestones & Deliverables Development of peak flow estimates and flood hydrographs for each design storm event. A summary of the hydrology effort will be summarized in the Alternatives Analysis Report.

Task 3-2: Alternatives Modeling – 2-D Hydraulic Model Stone will use the US Army Corps of Engineers (USACE) Hydrologic Engineering Center’s River Analysis System model (HEC-RAS; http://www.hec.usace.army.mil/software/hec-ras/) to develop a 2-D hydraulic model of the Batten Kill River and tributaries, both bridges and other pertinent infrastructure, and the wetland/floodplain complex. A 2-D model is most appropriate since the project involves expansion of flood flows over wide floodplains, and flows along the floodplains are impeded by various structures. Note that while a 2-D model excels at these types of hydraulic conditions, one limitation with the HEC-RAS 2-D model is that you cannot use the HEC-RAS bridge modeling features inside a 2-D flow area. However, HEC-RAS allows the user to create a combined 1-D/2-D model for


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projects that involve large floodplains (using the 2-D component of the model) and bridge structures (using the 1-D features of the model). Therefore, the Stone team anticipates creating a coupled 1-D/2-D model for this project.

Overall, Stone will use available LiDAR and topographic survey data collected under Task 2-1 as the base terrain data and use the model tools to create a 2-D computational mesh. The topographic data collected during the field work will be used to define the river channel dimensions, while available LiDAR will most likely be used as supplemental data to create floodplain surfaces, in any areas where topographic data was not collected. Stone will then add the infrastructure features to the model. Details of channel and floodplain roughness will also be added, boundary and initial conditions will be set, and developed hydrology will provide model input for various flood scenarios.

The model will route the flood event hydrograph through the channel, structures and wetland/floodplain complex. Stone will use the RAS Mapper and other output tools to provide visualizations of how water surface elevations, flood inundation, velocity and shear forces vary over space and time, within the project area, including along residential roads, property and the highway. Stone will run the model to estimate and produce visualizations of these variables for existing conditions and for each proposed alternative, including:

1. Increasing drainage structure size in the area, including the Route 7A and Railroad Bridge 76 2. Adding drainage structures and swales to the area to better accommodate floodwater flows 3. Relocation of Brookside Drive and flood proofing of the commercial building per NFIP

guidelines 4. Additional alternatives proposed by the consulting engineer which reduces flooding for the area

(Stone anticipates developing 1-2 more alternatives to be included in the analysis)

In order to improve the accuracy of the model through a strategic calibration effort, we had originally wanted to propose the installation of water surface data loggers (i.e. level loggers) at strategic locations within the project area, in addition to the collection of 4-5 flow measurements. The level loggers would be placed in four total locations, one in the upstream extents of the river, one in the downstream extents of the river, one in the floodplain upstream of the railroad bridge and finally one in the floodplain downstream of the railroad bridge. The level loggers would collect continuous water surface elevation data (i.e. every 6 minutes) over a period of time. While Stone will collect 1-2 flow measurements during field efforts to support the calibration of Manning’s n values within the model, the additional flow measurements were proposed to be collected during varying storm events. The water level data, and storm event flow data would be used as targets to fine tune parameters within the model and provide for a finer scale of calibration with respect to water surface elevation and flows. While this work is affordable, upon review of the project schedule (as outlined in Table 2 below) we would only have a few weeks of data collection before the model results are due on May 20, 2020. However, if the Town and stakeholders are interested in including this calibration effort, and there is room within the project schedule such that 2-3 months of data could be collected, the potential for including this effort in the scope of work could be discussed further. The costs to include this effort are discussed in Section 4 below.

Stone staff are well versed in use of HEC-RAS and have used it for analysis and design purposes on over 24 river and stream projects since 2012. Sixteen of those projects have been constructed to directly address flooding and infrastructure issues.


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Key Milestones & Deliverables Development of 2-D HEC-RAS model of existing conditions and all alternatives. A summary of results for existing conditions and each alternative, including visualizations will be

summarized in the Alternatives Analysis Report.

Task 4: Alternatives Analysis & Report Stone will develop an Alternatives Analysis as a means of comparing alternatives to each other such that an alternative can be selected to move forward to design and implementation. The metrics for comparing one alternative to another should be centered around maximizing the project goal. To reiterate, the project goal is to develop short- and long-term solutions to eliminate and/or mitigate flood frequency and extents within the project vicinity. The criteria that can be developed for this analysis could include 1) effectiveness in eliminating and/or mitigating flood frequency; 2) effectiveness in eliminating and/or mitigating flood extents; 3) evaluation of impacts to developed/undeveloped land, natural resources (floodplains, wetlands. etc.) and infrastructure (i.e. railroad, roads, etc.); 4) whether the project is deemed a short- or long-term solution; 4) is the project feasible (i.e. is the land available for acquisition/conservation; are the railroad owners on board with a bridge replacement, etc.); 5) project cost.

These are just a few examples we believe could be used in an evaluation matrix, however criteria can be adjusted and/or created during collaboration with the Town and stakeholders. Overall, the alternatives will be evaluated in a matrix table format against all of the defined criteria, and presented to the Town and stakeholders for review and alternative selection. The H&H effort will play a large role in evaluating project effectiveness, impacts and costs, therefore this effort will be summarized and included in the Alternatives Analysis Report. The H&H effort will also help to evaluate the importance of protecting or reclaiming lands for wetland conservation or for the benefits of flood storage. These considerations will be summarized in the Alternatives Analysis Report as well.

The Alternatives Analysis will include a cost analysis for each alternative. Stone will develop a Benefit-Cost Analysis (BCA) using FEMA methodology, such that the Town and stakeholders could apply for FEMA funding in the future (i.e. FEMA requires a BCA to validate cost effectiveness of a proposed project prior to receipt of funding). For each alternative, a Benefit-Cost Ratio (BCR) will be developed by dividing a project’s total benefit by its total costs. The BCR is essentially a way of expressing a projects cost effectiveness. The FEMA BCA Toolkit is an Excel based spreadsheet and will be used for this project (available at: https://www.fema.gov/benefit-cost-analysis).

Key Milestones & Deliverables Alternatives Analysis Report summarizing the alternatives comparison. Report will include a summary

of the H&H effort and protected/conserved lands evaluation. The report will also include the Benefit-Cost Analysis.

Task 5: Conceptual Design Plans & Costs Once an alternative is selected by the Town and stakeholders, Stone will incorporate the efforts and results of the work discussed above into the 30% conceptual design plans. We anticipate the design set will include the following sheets:

Cover Sheet Existing Conditions Sheet(s) Access and Staging Plan (s)


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Proposed Condition Sheet(s) Structure Modification Detail(s) and/or Drainage Structure Detail(s) and/or Road Relocation

and Flood Proofing Detail(s)

Key Milestones & Deliverables 30% design plans and cost estimate.

Task 6: Conceptual Design Report or Memo A final technical report or memo will also be prepared summarizing the design portion of this project, including calculations and a summary of construction costs for the selected alternative. Stone will submit a draft version to the Town and stakeholders prior to finalization, for review and comment, and will plan to incorporate any comments or revisions in the finalized version.

Stone will generate preliminary construction quantities from the design plans using either AutoCAD’s volumetric tools or other applicable calculations. The construction opinion of probable cost (OPC) will utilize 2-year and 5-year average unit cost data maintained by VTrans (http://vtrans.vermont.gov/cost-estimating), in addition to a review of unit costs from recent construction projects for similar bid items. Per standard cost estimating methodologies developed by the US Army Corps of Engineers, the conceptual, 30% design OPC will include a 20% contingency to account for unforeseen construction costs related to site conditions, variability in pricing, etc. This report will also include any updates to the BCA for the selected alternative, incorporating any changes to the design such that the Town and stakeholders will be ready to apply for FEMA funding.

Key Milestones & Deliverables Final report or memo summarizing the design portion of the project, with a summary of costs. Final edits to the Benefit-Cost Analysis for the selected alternative.

Task 7: Project Meeting Stone staff will participate in a final presentation with the Town, stakeholders and the public, presenting the final work and deliverables via a PowerPoint presentation or similar format. Stone will be ready to answer any questions and will document the meeting via minutes distributed to the group, following the meeting.

Key Milestones & Deliverables Final public presentation. Summary of meeting notes.


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3. Project Tasks, Deliverables and Schedule

The following proposed schedule assumes a notice to proceed date of January 15, 2020. Note that this schedule is structured to align with the dates and anticipated project closeout period (August, 2020) as expressed in the RFP. We view this schedule as draft and Stone is willing to adjust dates and tasks as the Town and stakeholders see fit. And for all meetings, Stone will be prepared to hold discussions, record minutes collaborate with the Town, landowners, stakeholders and partner organizations as appropriate.

Table 2. Project Tasks, Deliverables and Schedule

Project Task & Deliverable Description Weeks from Project Start

Completion Date

1 Meeting 1: Initial Meeting With Partners & Site Visit

Meet with stakeholders and landowners to relay project initiation, explain scope and schedule and gather additional information.

2 January 29, 2020

2 Completion of Field Work

Topographic survey and measurements of infrastructure (bridges, culverts, existing swales, etc.), limited geomorphic evaluation and field work complete.

12 April 15, 2020

Meeting 2: Optional 14 April 29, 2020

3 Alternatives Modeling Evaluation

Finalize 2-D modeling effort evaluating flood flow dynamics for existing conditions and 4-6 design alternatives at storm events of interest.

18 May 20, 2020

Meeting 3: Optional 18 May 20, 2020

4 Alternatives Analysis Report

Report with final set of alternatives (4-6) for stakeholder review/selection. Will include an evaluation of impacts to developed/undeveloped lands, wetlands, the river, railroad, etc. Will also include an interim Benefit-Cost Analysis for all alternatives, and an identification of suggested conserved lands.

20 June 3, 2020

Meeting 4: Modeling and Alternatives Analysis Meeting

Meet with stakeholders and landowners to discuss the Alternatives Analysis, model results and final set of alternatives.

20 June 3, 2020

Interim Review by BCRC and Partners

Review of all interim deliverables by project partners complete.

21 June 10, 2020


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Project Task & Deliverable Description Weeks from Project Start

Completion Date

5 30% Design Plans and Specifications for Selected Alternative

Complete designs, specifications and costs for the selected alternative to the 30% design level.

27 July 22, 2020

Meeting 5: Optional 27 July 22, 2020

6 Final Benefit-Cost Analysis & Report

Finalize Benefit-Cost Analysis for selected alternative using 30% design plan details, and Final Report.

27 July 22, 2020

Final Review by BCRC and Partners

Review of all final deliverables by project partners complete.

28 July 29, 2020

Meeting 6: Selectboard Meeting

Meet with the Selectboard to discuss the final plan and report.

29 August 5, 2020

7 Final Plan Presented Publicly

Presentation of final study and plan to stakeholders and the public via a Town and/or stakeholder sponsored public meeting. Final plans, report and associated documents available digitally and in hard copy.

30 August 12, 2020


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4. Costs

Error! Reference source not found.3 below provides a breakdown of costs for the project. Travel expenses are exclusively based on mileage at standard reimbursement rates set by the federal government.

Table 3. Cost Table

Task/Phase Project Team

Expenses Total Cost

Members / Hours / Cost Name Hours Rate/Hr Cost

1 Meetings and PM Gabe Bolin 56 $133 $7,448

$727 $9,423 Meghan Arpino 12 $104 $1,248

2 Field Work Gabe Bolin 20 $133 $2,660

$1,206 $8,150 Meghan Arpino 28 $104 $2,912 Branden Martin 14 $98 $1,372

3 Alternatives Modeling

Gabe Bolin 16 $133 $2,128

$0 $10,803 Peter Lazorchak 3 $133 $399 Jody Stryker 20 $133 $2,660 Meghan Arpino 54 $104 $5,616

4 Alternatives Analysis Report

Gabe Bolin 40 $133 $5,320

$0 $9,868 Peter Lazorchak 4 $133 $532 Meghan Arpino 16 $104 $1,664 Branden Martin 24 $98 $2,352

5 30% Designs

Gabe Bolin 48 $133 $6,384

$0 $13,250 Peter Lazorchak 10 $133 $1,330 Meghan Arpino 8 $104 $832 Branden Martin 48 $98 $4,704

6 Final Benefit-Cost Analysis & Report

Gabe Bolin 28 $133 $3,724 $0 $6,516 Meghan Arpino 8 $104 $832

Branden Martin 20 $98 $1,960

7 Final Presentation Gabe Bolin 8 $133 $1,064

$0 $1,896 Meghan Arpino 8 $104 $832

TOTAL COST $59,906

As discussed under Task 3-2, Alternatives Modeling – 2-D Hydraulic Model, if the Town and stakeholders chooses to include the installation of level loggers and the additional flow measurements, an additional $3,480 would be added to the project cost (under Task 2, Field Work), resulting in a revised total cost of $63,386.

For legal proceedings, a 50% surcharge will be added to the professional rates for sequestered preparation time and time spent in depositions, public testimony, court, and hearings. All rates are subject to revision without notice. All subcontracted services, material costs, field supplies, outside services, rental fees, freight and shipping charges, overnight delivery fees, rental vehicles, meals, travel, lodging, and other project-related direct expenses will be invoiced at cost plus 10%. Use of equipment,


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materials, and disposable supplies owned by Stone Environmental, Inc. will be invoiced at fixed unit rates. A summary of these rates will be provided upon request. Invoices are typically issued monthly for services provided and expenses incurred during the prior month. Invoices are due and payable within thirty (30) days of the invoice date. Preparation of custom invoice formats and documentation of itemized charges will be invoiced at $83.00 per hour plus expenses. A late payment service charge of 1.5% per month will assessed against overdue balances.

Documents

Proposal for Read Farm Lane / Brookside Drive Flood Study ...dorsetvt.org/.../stone_enviro_proposal_12-9-19.pdf · 12/9/2019 · wetland and floodplain complex, and the interplay