Request for Qualification Statements - Breakwater Improvements - Sedimentation Study

Bid Postings • Request for Qualification Statements - Breakw Skip to Main Content Create a Website Account - Manage notification subscriptions, save form progress and more. Website Sign In City Government Our Community Doing Business Just Visiting How Do I Search Home Bid Postings Print Sign up to receive a text message or email when new bids are added! Print Bid Title: Request for Qualification Statements - Breakwater Improvements - Sedimentation Study Category: Harbor Status: Closed Description: CITY OF BELFAST REQUEST FOR QUALIFICATION STATEMENTS MAINE DEPARTMENT OF MARINE RESOURCES SHORE AND HARBOR PLANNING GRANT PROGRAM SEDIMENTATION STUDY FOR BREAKWATER IMPROVEMENTS 1. PURPOSE OF THIS REQUEST In July of 2023, the City of Belfast was awarded a Maine Department of Marine Resources Shore and Harbor Planning Grant in the amount of $50,000.00. The City will utilize these grant funds, in conjunction with $5,000.00 in City cash matching funds, to provide an engineering study to determine the effects extending the existing breakwater by 60 feet may have on currents and sedimentation around the breakwater and on adjoining areas of the harbor. This information will allow the City of Belfast to determine the best options to move ahead with future planning for the breakwater. An engineering study, entitled “Report on Breakwater Improvement Options” was recently completed that considered present breakwater conditions, documented the current structure, and offered alternatives for renovation and expansion that would provide protection of the City Landing infrastructure from anticipated sea level rise and related stresses resulting from climate change. This study included detailed information regarding design options, construction estimates, regulatory approvals, fabrication methods, and also included a limited geotechnical investigation. The chosen design option for extending the breakwater brought up a concern of whether that option would create any sedimentation/silting issues. The City of Belfast Harbor Advisory Committee and the Belfast City Council felt this question should be investigated and a sedimentation study completed before continuing with this breakwater improvement project. The City of Belfast now seeks a qualified individual or firm to serve as Engineer for this project. This Engineer will work with various City individuals and entities, including but not limited to, the Mayor and City Council, the City Manager, the Harbor Master, the City Planner, and the Harbor Advisory Committee, to carry out the specific activities of this project. The scope of services to be performed must be started no later than August 31 st , 2023, and must be completed no later than December 31 st , 2024. A total of $55,000.00, from the combination of the aforementioned $50,000.00 in grant funds and $5,000.00 in cash matching funds, has been allocated to compensate the Engineer for performing the required scope of services. The Engineer will be paid by the City periodically during the duration of the project on a percentage completed basis, with a maximum of four payments allowed to be made. 2. SCOPE OF SERVICES REQUIRED The following is the scope of services that the Engineer will be required to perform. Some of these services will be performed exclusively by the Engineer, while others will be performed in conjunction with one or more of the aforementioned individuals and/or entities: Task 1 - Data Collection (estimated budget of $5,600 for this task) In support of the hydrodynamic, wave, and sediment modeling, a data collection effort will be conducted. Targeted data sources are listed below: Publicly available bathymetric data including USACE Hydrographic Surveys , surveyed bathymetry data (depending on availability) of Passagassawakeag River between the Belfast Armistice Bridge and Belfast Bay. The dimensions and plans for the coastal structures within the model domain including the existing breakwater, the Belfast Armistice Bridge, and the Acadia Highway bridge. Grain Size analysis of bed sediments from previous studies. Gulf of Maine Operation Forecast System (GoMOFS) tidal level and current predictions. North Atlantic Comprehensive Coast Study (NACCS) predicted return intervals for extreme water levels and wave heights. In the event data sources are not available, efforts will be made to identify other sources, and if not available, the modeling effort will be tailored, and results qualified to reflect any data limitations. Deliverables Bathymetric, topographic and coastal boundary conditions for modeling Task 2 - Coastal Modeling Task 2.1 - Wave Modeling (estimated budget of $6,100 for this task) A Delft 3D Wave model will be used to simulate the wave heights around the breakwater using the spectral SWAN model. The D-waves module computes wave propagation, wind-wave generation, energy dissipating, wave breaking, refraction, shoaling, and directional spreading. The bottom orbital velocity of waves in shallow water, an output of D-Waves, can create a bed shear stress on top of the shear stress generated by currents. Deliverables Wave characteristics and significant wave heights near the project site Task 2.2 - Hydrodynamic Modeling (estimated budget of $6,100 for this task) The synthetic tidal storm hydrographs and wave conditions for the design storm as the boundary conditions to the model will be developed from the data above. The return period of the design storm will be determined with the design team. The flow across the boundary in Belfast Bay will be calculated using the NOAA Gulf of Maine Operational Forecast System (GoMOFS). Two (2) Two-Dimensional (2-D) hydrodynamic model configurations for each the existing condition with the present breakwater and the proposed extended breakwater structure will be modeled using HEC-RAS. The conditions will be simulated for both geometries for the design storm and a daily tidal condition. The tidal hydrodynamic boundary conditions will be simulated on both existing and the proposed condition models and results of velocity, depths, water surface elevation (WSEL), and bed shear stress will be developed. The streamlines and velocity vectors will be plotted to identify the flow patterns. We will use the 2-D HEC-RAS hydrodynamic model with the currents and tidal boundary conditions to simulate tidally influenced water bodies due to the robustness and the stability in the model compared to comprehensive coastal models. Deliverables Hydrodynamic model of existing and proposed conditions Task 2.3 - Critical Shear Stress Assessment (estimated budget of $2,900 for this task) Grain size distribution from a past sieve analysis (bed gradation) will be used to determine the representative d50 grain size for a critical shear stress analysis. A Shield’s critical shear stress analysis will be performed to find out the threshold of the sediment movement, based on non-cohesive d50 grain size found above. Assuming the bed material to be non-cohesive sediments will enforce conservativeness to the sediment movement. A comparison between the existing and proposed 2-D velocity contours will indicate the possible areas of impact due to the proposed conditions. A comparison between simulated bed shear stress from both the hydrodynamic modeling as well as due to the orbital velocity of the waves with the critical shear stress will indicate the areas that are vulnerable for sediment movement. With this approach we can decide if the proposed conditions will impact new areas. Deliverables A “heat map” of shear stresses with potential to result in sediment movement within affected area due to the proposed breakwater condition Task 2.4 - Sediment Accumulation Rate Assessment (estimated budget of $3,800 for this task) Bathymetry data is available from the USACE hydrographic survey database of the Belfast Harbor just downstream of the project area extending southeast from the breakwater to Patterson Point. Bathymetric survey data was collected in 2011, 2018, and 2022. An average sediment accumulation/loss rate will be calculated based on bathymetric changes for the 11-year period and can be extrapolated for future predictions. Deliverables An estimate of sediment accumulation rates and potential accelerated (or reduced) sediment accumulation within the affected area due to the proposed breakwater condition Task 2.5 - Sediment Plume Modeling (estimated budget of $7,000 for this task) The HEC-RAS Sediment Transport module will be used to determine the bed level change from the load determined in the sediment accumulation rate assessment above. The HEC-RAS sediment transport modules can simulate sediment loads flowing into the model and will assume that the native bed sediments are not eroded. The output is a bed level change map to determine areas of erosion and deposition. Deliverables A 2-D contour map of sediment transport showing erosion and deposition zones in feet (or inches, as applicable) Task 3 - Reporting (estimated budget of $15,000 for this task) A technical report will be developed to summarize the inputs, model components, and results from the hydrodynamic, wave, and sediment models discussed above. Deliverables A comprehensive technical report Task 4 - Project Management (PM) and Meetings (estimated budget of $8,500 for this task) This task will include the following: Management, tracking, and communications relating to the project budget, schedule and deliverables. Attendance at up to two virtual meetings: one following data collection any hydrodynamic modeling and a second following the draft report. Deliverables Monthly (at a minimum) projects status reports Detailed invoices and budget statuses Meeting agendas and summary notes 3. QUALIFICATION STATEMENT FORMAT, EVALUATION FACTORS Interested individuals or firms are instructed to follow the format by providing a cover letter and responding to each of the three numbered (3.1-3.3) evaluation factors listed below; the percentage weight for each