Approved Meeting Minutes
Herring River Restoration Committee (HRRC)
Cape Cod National Seashore Headquarters
Wellfleet, MA
July 10, 2013
9:30 am-5:00 pm
Members Present: Tim Smith, Hunt Durey, Eric Derleth, Steve Spear, Steve Block, Charleen Greenhalgh, Hillary Greenberg
Others Present: Margo Fenn, Don Palladino, John Portnoy
Administration/Coordination:
Communications/Coordination with Friends of Herring River (FHR): Don Palladino reported on FHR activities. He noted that the final invoice had been submitted for the Division of Ecological Restoration (DER) grant for Project Coordination. There is approximately $12,000 remaining in the Conservation Law Foundation (CLF) grant to continue this work through the end of September 2013.
In other grant news, Don Palladino noted that FHR is waiting for a contract from the Massachusetts Environmental Trust (MET) and a revised National Oceanic and Atmospheric Administration (NOAA) grant application had been submitted. FHR also needs to submit a progress report to the Massachusetts Bays Program (MBP) by July 30, 2013.
Eric Derleth asked about how to begin the Phase 1B archaeological investigations for the Restoration Project. Margo Fenn agreed to check with Bill Burke on this and about progress in completing a Programmatic Agreement with the Massachusetts Historical Commission (MHC).
Don Palladino also reported that FHR is working with a local accountant to set up an online database to track grant activities. He noted that the FHR Annual Meeting would be Tuesday, August 20, 2013 at 4:00 pm at the Wellfleet Senior Center.
Approval of Minutes: The Committee voted to approve the minutes of the June 19, 2013 meeting.
Schedule of Meetings: The Committee approved the following schedule for upcoming meetings:
July 18, 2013: MOU Working Group meeting
August 15, 2013: HRRC regular meeting
August 21, 2013: MOU Working Group meeting
September 12, 2013: HRRC regular meeting
Charleen Greenhalgh also noted that the Federal Emergency Management Agency would set up a meeting in August with the Outer Cape towns to review the Preliminary Draft FIRM maps. (Final date for this meeting was later set for August 15, 2013 at 4:00 pm at the Truro Community Center.)
Informational Updates:
Update on MOU III Development: Margo Fenn reported that the MOU Working Group had met in June to review consultant Catherine Barner’s draft report and to make modifications to the Preliminary Draft MOU III. The Working Group is recommending the creation of a non-profit management organization to assume responsibility for managing the Restoration Project through the implementation phase. One option under consideration is modifying the mission of the Friends of Herring River to play this role. Don Palladino noted that FHR is seeking legal advice about what changes would be necessary in its Articles of Incorporation and Bylaws if it were to become the management entity. Don Palladino is preparing a summary of the pros and cons of having FHR assume this role, which will be reviewed by the
MOU III Working Group at its July meeting.
Consultations with State Agencies: HRRC has not received any additional feedback from the MA Natural Heritage and Endangered Species Program (NHESP) staff. A follow up meeting with the MA Department of Environmental Protection (DEP) has been scheduled for August 12, 2013. Hunt Durey agreed to provide a copy of his email to DEP (summarizing permitting issues to discuss) to other HRRC members. Tim Smith will check back with NHESP.
DEIS/EIR Response to Comments: Tim Smith is developing a more detailed description of the Adaptive Management process to include in the Final Environmental Impact Statement/Report (FEIS/EIR). This should provide the basis for answering a number of the concerns raised in comments on the DEIS/EIR. There are a number of issues that will require Committee discussion. The HRRC agreed that a portion of the August meeting should be devoted to this discussion. Tim Smith agreed to send out his write-up of the Adaptive Management approach prior to the August HRRC meeting.
Restoration Project Work Plan: At the June meeting, the HRRC reviewed a draft Gantt chart of upcoming project activities. Tim Smith reported that he had begun the process of converting the work program into a Microsoft Project format. This entails creating discrete tasks and subtasks. The Committee reviewed a sample section and discussed how to use it and who should have access to it. While it is important for HRRC members to get regular updates on the work program, it would probably make sense for just one or two people to manage it. Tim Smith agreed to continue to develop the work program in Microsoft Project and provide HRRC members with a pdf copy of the revised draft to review.
Low-lying Property Outreach (LLP): Margo Fenn and Don Palladino reported on FHR efforts to explore options for the Feil property. The Committee reviewed a draft list of the structurally affected properties and discussed needed follow up actions for each property. The group agreed that it would make sense to hold a few neighborhood meetings with groups of affected landowners, perhaps in August. There are a number of property owners who did not respond to the letter that was sent in October of 2012. The Committee agreed that individual letters should be sent to these owners to remind them to contact the HRRC.
Margo Fenn and Tim Smith agreed to develop a follow up letter to those property owners who have not responded to the HRRC. Margo Fenn will prepare a revised list of needed follow up steps for each affected property. Don Palladino agreed to check with the FHR Board about informally contacting some of the owners who have not responded.
Workshop with Fuss & O’Neill and Woods Hole Group (WHG)-Mill Creek Dike and Tide Gate Designs: Nils Wiberg and Dean Audet of Fuss & O’Neill and Kirk Bosma of WHG joined the meeting in the afternoon for a workshop on the Mill Creek dike and tide gate options. Representatives from the Chequessett Yacht and Country Club (CYCC) also participated, including: Chuck Edmondson, Jim Garpow, Jack Whalen, Bob Hubby and David Stott.
Nils Wiberg provided a summary of Fuss & O’Neill’s work to date on the Mill Creek dike options. He presented four structural alternatives for the dike design including:
-An earthen dike (with 3:1 horizontal to vertical slopes)
-A hybrid earthen dike with a single retaining wall (with 3:1 horizontal to vertical slope)
-A double-wall structure made of steel sheeting or concrete caissons with equipment access at the crest of the structure
-A single-wall structure made of steel sheeting or concrete caissons with equipment access at marsh grade
Using a preliminary comparative constraints summary table, he reviewed the advantages and disadvantages of the different design options. The table includes evaluation criteria for:
-Natural Resources and Environment (e.g. minimizing impacts to fish passage, shellfish, rare species and wetland vegetation)
-Physical Processes (e.g. facilitating drainage and minimizing scour and sedimentation)
-Construction Phase (e.g. minimizing construction costs and duration, encouraging ease of operation)
-Post-Construction Phase (e.g. minimizing operations and maintenance costs, addressing safety and security concerns, addressing aesthetic concerns)
The earthen dike option has the largest footprint (dike would be 70 feet wide), and therefore the greatest amount of construction disturbance. It also would have the longest culvert, which is not conducive to fish passage. It has a lower construction cost than the hybrid dike or double-wall options but higher than the single-wall structure.
The hybrid earthen dike option would have a smaller footprint (dike would be 40 feet wide) and therefore a shorter culvert. It has an intermediate relative construction cost.
The double-wall structure would have a substantially smaller footprint (dike would be 20 feet wide) and shorter culvert. The crest of the dike would be wide enough to allow equipment access but this option has the highest overall construction cost.
The single-wall structure has the smallest footprint and shortest culvert length. This option would provide both the lowest construction cost and least wetland impacts, but an elevated catwalk would be needed to access the tide gates. In addition, a maintenance access route would be needed from one side of the structure; this route would be a reinforced surface to support large vehicles/equipment, set at or above marsh grade (the higher the elevation of this route, the more the approach resembles the hybrid option).
The workshop participants discussed the options and the weighting system for the evaluation criteria. The group suggested some changes in the weighting criteria, noting that facilitating good drainage at all stages of the tide and minimizing construction duration are important considerations. CYCC representatives commented that the dike would not be very visible from the golf course, so aesthetic concerns are not paramount.
The group discussed construction access to the site. The site could be accessed through the CYCC property or from another private lot to the north of Mill Creek. The group agreed that it would make sense to provide access through or around the western perimeter of the golf course provided that the dike is constructed at the same time that the lower fairways of the course are being reconfigured. This would be a way to minimize disruption and the time that the golf course would have to be shut down for construction required for both projects.
After discussing all the options, the group agreed that the earthen dike and the single-wall structure should be selected for further evaluation. Fuss & O’Neill will prepare more detailed designs for these two options.
Nils Wiberg then presented the alternatives for tide gates including:
-Slide gates with independent flap gates
-Integral combination slide/flap gates
-Inverted weir timber stop log gates with independent flap gates
Using a preliminary comparative constraints summary table, Nils Wiberg reviewed the advantages and disadvantages of the different tide gate alternatives. Similar to the analysis for the dike structure options, the tide gate summary table uses evaluation criteria for:
-Physical Processes (e.g. facilitating drainage and minimizing scour and sedimentation)
-Construction Phase (e.g. minimizing construction costs and duration, encouraging ease of operation)
-Post-Construction Phase (e.g. minimizing operations and maintenance costs, adaptability to sea level rise conditions, capability to meet FEMA standards for flood protection, and aesthetic concerns)
Wiberg noted that slide gates need regular maintenance. Jack Whalen asked if a pump would be needed to facilitate drainage. Tim Smith noted that the WHG hydrodynamic modeling report found that this would not be necessary. All alternatives assume that the tide gates will operate passively; there will be no power provided at the dike, though if this were determined required to enable future operation, it could potentially be provided. The integral combination slide/flap gates provide the lowest construction costs and less potential problems with sedimentation since normal flows are directed through the gates to clear sediment. Workshop participants agreed that the combination gates would provide the most flexible, adaptable and reliable alternative.
The next step is for Fuss & O’Neill to prepare a technical memorandum summarizing the alternatives analysis for both dikes and gates. They will develop more detailed engineering drawings and estimate construction costs for the selected alternatives.
Hydrodynamic Modeling Issues: At the June HRRC meeting, the Committee had a brief discussion about hydrodynamic modeling. Steve Spear had noted that even though the highest tide ever recorded in Wellfleet Harbor (during the blizzard of 1978) reached only 9.3 feet NAVD, the new FEMA FIRM maps are based on their calculated synthetic storm tide elevation of 15 feet in Wellfleet Harbor. He advocated for having WHG run two new model scenarios, one with a Harbor boundary forcing of 11.9 feet (one-tenth of a foot lower that his projected height of the new Chequessett Neck Road dike) and one for FEMA’s synthetic storm tide of 15 feet. The Committee had agreed to talk with Kirk Bosma to explore this question.
Kirk Bosma noted that WHG did model the 11.9 foot storm surge, looking at both water surface elevation and duration. He made the following observations:
1)~Duration of surge is important. ~This is probably significantly more important than the peak surge elevation for this site, since the Herring River system is so extensive.
2)~Peak surge will be affected by how low the prior low tide goes.~For example, if there is a draw down prior to the surge, that may reduce the maximum surge elevation, particularly farther up in the system.~ WHG did not include the draw down effect that is typically a component of tropical storms.
3)~The increase in surge for areas is likely due to a larger volume of water entering the system during about 20-30 minutes around the peak because of the higher head difference across the sluice gates. It takes a while for this to propagate farther up into the system; however.~ There is a phase delay in the peak elevations.
4)~Some of the upper sub-basins experience an increase in water surface elevation for a longer-duration event.~ This happens when embankments (railroad, roads, etc.) are overtopped and sheet flow starts to happen (similar to High Toss Road).~ ~This scenario (long duration) is very extreme, however.
5)~If you use storm elevation records from Boston and use standard GEV extreme analysis, the 11.9 foot event would correspond to a 1500-year storm (as seen in the chart), if you want to use that type of return-period basis.~
6)~While it is possible to imagine a storm surge scenario that could be longer and higher, all of this can be controlled with the Chequessett Neck dike tide gates.~Right now, we can say based on our design, the historic 100-yr storm of record would not go over 7.5 feet with the dike fully open.
Tim Smith reminded the group that the Restoration Project would be implemented incrementally with careful monitoring and adaptive management. By the time that the gates are fully open, the managers of the Project would have a much clearer understanding of how the system responds to different storm conditions. Eric Derleth concurred and noted that the operations and maintenance plan can be modified over time.
Hillary Greenberg commented that the public might be confused about why we are not designing the dike to FEMA flood standards. Kirk Bosma reiterated that constructing a flood-certified structure at CNR may have limited value because the current FEMA modeling also predicts overwash at Duck Harbor during their modeled 100-yr event, meaning the Herring River flood plain would remain exposed to the FEMA mapped 100-yr flood plain whether the CNR dike was certified or not.
The Committee agreed that it is important to develop a fact sheet explaining the relationship between the WHG model and the FEMA flood projections. Tim Smith and Kirk Bosma agreed to work together to draft a document to explain the differences.
Documents referred to in the meeting:
-Minutes of the June 19, 2013 HRRC meeting
-Draft Comparative Constraints Summary Tables for Mill Creek Dike Designs and Tide Gate Options, Fuss & O’Neill, July 2013
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