Conservation Commission

NASHUA CONSERVATION COMMISSION Minutes of the February 5, 2013 Meeting A. Call to order A regular meeting of the Nashua Conservation Commission was called to order at 7:00 PM on Tuesday, February 5, 2013. B. Roll call Acting Vice-Chairman Peggy Trivilino, presided; Members of the Commission Present: Michael Gallagher, Treasurer Richard Gillespie, Clerk Cynthia Overby Members of the Commission Absent Also in Attendance: Chris Sullivan, Planning Department Alderman Jim Donchess Cynthia Balcius John Vancor Jameson Paine Dave McNamara C. Approval of minutes: • January 15th – regular meeting MOTION BY COMMISSIONER GALLAGHER, SECONDED BY COMMISSIONER GILLESPIE, TO ACCEPT AND PLACE ON FILE THE MINUTES OF THE JANUARY 15, 2013 MEETING MOTION CARRIED D. Old Business: None E. New Business: Coliseum Ave, Tax Map A, Lot (s) 1428 and 1548. Owner-Mine Falls Condos and One Park Place LLC. Drainage Easement, Prime wetland. The purpose of this application is to repair an existing culvert outfall located on the Bank Nashua River. Work involves reconstructing an existing outfall structure including one section of 36 inch RCP pipe the existing masonry blockhead wall and 12 inch erosion stone outlet protection. The work is located within the prime 75 foot wetland buffer of the Nashua River. Ward 1 Cindy Balcius with Stoney Ridge Environmental introduced herself as well as Doug Boyce from Hannaford and Pete Julia from Farmhouse Land Development, the engineer who did the work as far as designing the outfall and recommended stone size who were not able to make the meeting due to the flu. Ms. Balcius went over this history over the last couple of months. Doug Bois had just been made aware of an erosion problem with the outfall located in a drainage easement next to Mine Falls Condominiums. The drainage pipe goes across Coliseum Ave. into Hannafords where it drains an existing detention basin. The easement was built as part of the condominiums back in 1991. When Hannafords was built, they were allowed to tie in here. Unfortunately nobody has thought to check the outfall during the entire time. In the early fall, somebody noticed that there was an issue with the outfall,l that it had severe erosion problems. Looking at the picture, the last 8 foot section of the 36" cement pipe has been undermined and separated from the pipe behind it as well as the masonry block wall has completely collapsed underneath it. We looked at it and contacted the engineer to do the design work. They felt it was a public safety issue as well as an environmental issue. Ms. Balcius prepared the Permit by Notification for the Wetlands Bureau for bank impact and put together the wetlands buffer impact application to the Conservation Commission. Overall, Stoney Ridge Environmental is proposing 350 square feet of permanent impact in the bank. It's to rebuild a section of bank and then fortify it. Ms. Balcius indicated that they incorporated hard armor along with some vegetative cover. They're not sure what was there before for outfall protection and may not have been anything. As the project was started, another issue came up that confounded it a little bit and that was that there's a 20 foot conservation easement held by the City and signed in January of 1981. The drainage easement bisects the conservation easement on the river's edge which was noted in the application. Cindy Balcius stated that they put together the application, filed the permit by notification to the Wetlands Bureau, and stepped through the applicable codes, addressed all the performance standards, and went through all the special exception criteria. Commissioner Gallagher went through an overview of what the Conservation Commission would be looking for: project is presented going through the history, Q &A time for the Commission, Commission will decide whether they want a site walk and if so, Stoney Ridge Environmental to come to the next meeting to answer any questions relative to the site walk, and Commission to give positive or negative recommendation Cindy indicated that she'd go through what was designed to replace what was out there. They're going to keep the same size RCP and will replace the last 8 foot section. What you see from the photos the type of masonry rock wall, we're going with a total wing wall which is a substantial improvement to what was out there. Commissioner Gillespie asked if it was pre-cast or cast in place. Cindy said it was pre-cast. There's a cross section of what we intend to do. We're going to transition the site into the existing embankment. In the rip rap area, we're going to insert a 2 inch PVC pipe about 2 feet into the ground with 6 inches of that sticking up when the construction is done. In spring conditions, we want to insert whips using red rosier dogwood. We start them in the tube and then pull the tube out. That allows bio-stabilization within the rip rap so they're incorporating plantings stabilizing it by hard armoring and transitioning it into the existing slopes. Commissioner Trivilino asked what hard armoring meant and where does the vegetation come in. Cindy said it was rock instead of vegetation. Cindy showed the outlet on the diagram and said when the outlet flows down, you have a cross section and it will be rip rap. On the slopes that transition into the natural subsoil, we're going to plant those. Commissioner Overby asked if it saw a lot of high velocity flows. Cindy said the outlet is sized based on the detention basin size. There is one catch basin in the Mine Falls parking lot that also flows into it. It was sized at the time of Hannafords construction to ensure that it discharged whatever storm the detention basin is designed for, which she didn't know. Commissioner Gallagher stated that they might want to change your hay bales to straw bales. We don't allow hay bales in Nashua because of the seeding. Commissioner Gillespie asked how far down the bank will the apron extend to the water. Will it go into the water? Cindy said no. The reference flood elevation of the river will go right above that. 2 Commissioner Gillespie then asked if that size stone would be adequate for a 100 year flood condition. Cindy believed that Pete did size it accordingly knowing the history of the river. He did do research into the hydraulics of the river itself too. At the base of that, he has what he calls "anchor rocks" which are a little bit bigger. Commissioner Gillespie asked if the existing concrete debris was going to be removed. Cindy said yes. Commissioner Trivilino was curious about the rip rap and the rocks. If we had a flood that submerged the apron, what would keep those rocks from lifting up and floating away? Cindy said the rocks are actually sized appropriately so that they aren't lifted up and taken away. When they're emplaced, they're embedded and with the plantings on the side, they're anchored even more. Commissioner Gillespie stated the report mentioned fertilizer. Cindy said no fertilizer will be utilized for plantings at all. Commissioner Gillespie said there's a difference in the starting date on one application versus the other. One has March 1st as a start date and the other one has June 30th. Cindy stated it was hopeful whatever date they can start they want to do it as soon as possible. As soon as they get all their approvals from Neil (who is this?), that will determine it. Commissioner Trivilino asked what is the net environmental impact Ms. Balcius stated there's an unstable outlet right now that has basically sloughed the embankment right off. It's unstable and the culvert itself is undermined so there's more soil going into the river and topping that area with sediment at the base of the outlet. By rebuilding, stabilizing it and adding plants, it’s an improvement over the existing condition Commissioner Trivilino asked if during the construction do you have to use heavy equipment. Cindy said they won't have to use a bulldozer but they'll probably be using an excavator. The area upslope from the culvert outlet is a grassed area beside the condominium. Hannafords will use machinery over the grassed area, do their work and we stabilize it. It includes some plantings above the culvert headwall of Red Osier Dogwood. Commissioner Gallagher mentioned he saw additional plantings on existing conditions and asked if they were being planted as well such as White Pine, Black Cherry and Grey Dogwood. Cindy indicated that they were taken from Mine Falls old plans. They're plantings that were already there. The area we're working in is very constrained. We're not taking any big trees as there aren't any there. Commissioner Gallagher asked if they knew how many trees would be taken down as it mentioned in the application tree removal was checked off as yes. Cindy stated none. They are taking down some saplings. Commissioner Gillespie asked if they had to pour a foundation for the wing wall. How is that supported? Cindy said there is a footing in and wasn't sure if they were pre-cast. Commissioner Gillespie said they were excavating a trench of some sort along the edge of the bank. Cindy said right underneath there, it’s already undermined at this point. There's not much that needs to be removed other than just moving it to the side. It's all weeds. There's a hole underneath the culvert. Commissioner Gillespie asked if they needed a site walk. It was the consensus of the Commission to have a site walk on Monday, February 11, 2013, at 9 a.m. Cindy said that date was fine with her and she hoped to get the engineer there as well to answer any questions. City of Nashua (Owner) Division of Public Works (Applicant) Proposed Broad Street Parkway - beginning at the intersection of Blue Hill Avenue and Broad Street, continuing along the 3  southern side of existing railroad tracks and traversing over the Nashua River with a bridge crossing, terminating into Pine Street at the intersection of Ledge Street and Central Streets - requesting Special Exception to work in the 75-foot prime wetland and wetland buffer of the Nashua River and Nashua Canal to construct the Broad Street Parkway - a new 1.8 mile two- lane roadway, along with associated development such as infrastructure, retention ponds, sidewalks, street lighting, retaining walls, Nashua River Canal Outlet Control Structure, replacement of two bridges, new signalized intersections, and demolition of six existing structures. Ward 4. Commissioner Overby asked if the railroad tracks go across the Nashua River. Commissioner Gillespie said yes in back of Thoreau's Landing, near Nashua Swim and Tennis Club. Dave McNamara with Fay, Spofford and Thorndike introduced himself as well as John Vancor with Hayner Swanson who's the Program Manager working for the City, and Jamison Payne with Normandeau is handling the environmental work. Mr. McNamara indicated that the Broad Street Parkway begins up on Broad Street intersection of Blue Hill Avenue and the DMV entrance. There's a quarter mile of work on Broad Street with some widening crossing the railroad tracks. The new Parkway is proposed to begin a couple hundred feet west of the railroad crossing. It will run parallel to the railroad tracks, crosses through the old Fimbel Door site, there's a pinch point where the Nashua River comes in behind #44 Broad Street. The Baldwin and Fairmount Bridges will be demolished and longer bridges will be installed to cover the railroad and the Parkway. As you come out of Fairmount Street, it continues along the railroad for a few hundred more feet and then they diverge and there's a new river crossing with the Parkway to go into the Mill Yard area. Once in the Mill Yard, the alignment comes through the old boiler house buildings, which has been recently demolished, and ties into the existing Pine Street Extension. The Parkway terminates at the intersection of Ledge and Central. There is a small amount of work on Ledge and Central Streets as part of this project and ties in with the recent work that's been done in the tree streets. Individual wetland impacts. Mr. McNamara said there were 4 major areas where the impacts are located. The first one is 44 Broad Street. There will be a proposed large retaining wall along the edge of the Parkway. There's a steep slope going down and then the City sewer line runs along a platform just above the river. There's no jurisdictional impacts in this area but there are impacts to 75 foot prime wetland buffer for the City. There's another impact a little bit lower. It's a wetland buffer to handle an outfall from a detention basin. Moving down the Parkway, there's 3 interior wetlands. One of them we're going right over and will be a complete fill. We show a 40- foot buffer around it. There's a slightly smaller one northwest of it. We stay out of the wetland directly but we do get into the buffer with some slope work coming off of the proposed detention pond. To be conservative, we're filling the entirety of this pocket wetland. They did show the entirety of the 40- foot buffer and covered it as an impact and some of it beyond our limits of work. Commissioner Trivilino asked how much is getting filled in. Mr. McNamara showed the pocket wetland. It's about 28 (Makes no sense). There are parts of the buffer that we're not getting into. Further to the south, Mr. McNamara indicated they were approaching the Nashua River Bridge crossing. They hit a pinch point between the river and the railroad tracks. They have retaining walls on both sides of the Parkway. They're tight to the railroad tracks and the river. We're trying to minimize our impacts on both sides. To further minimize the impact on the river side, we're proposing a cantilevered sidewalk. The sidewalk is going to hang out over the retaining wall off the side of the bridge. He referred the Commission to the colored plan. 4 Commissioner Trivilino asked what if the river really flooded. Dave McNamara said this is in the 500 year flood zone and it's still 10 to 12 feet below the top of the wall. The river is dam controlled not far from here so you'd be able to mitigate issues of that nature. Mr. McNamara said the area does have jurisdictional impacts of about 300 something square foot and they do show some temporary impacts into the riverbank to build the wall. The 75 foot buffer covers most of the Parkway. As you approach the bridge there will be two sets of piers in the water and it looks like we'll be able to get one of those sets just outside of the top of bank. For the purposes of permitting, we left them in. That's the permanent impact of the bridge in the wetland areas. As we land on the other side we are within the 75 foot buffer again. The abutment is going to be back behind an existing stone block wall. We're going to set the abutment behind it and we'll take off the first few rows of block and the bridge is going to come through it. There will be no wetland impact on this site to construct and build a bridge but there will be impacts to that 75 foot buffer. We're grading down a little bit to fit the girders in. Commissioner Trivilino asked about the one set of piers that could be set back into the bank. Would it be less damaging overall to put those piers into the river bed as opposed to putting them through the bend? Dave McNamara said it's a flatter area as you come up. We're drilling through a really steep side slope to get them in. It will be outside the top of bank area. For construction purposes, Mr. McNamara has shown for temporary impacts is a trestle crossing the river with a number of temporary piles to support it. It will give the contractor the ability to build a temporary structure in the river in order to build a bridge. The contractor will have his own work plan. We'll permit something that gives him a reasonable way to do work over the water. Mr. McNamara indicated the last area of impact is the canal that comes up into the Mill Yard area. The realigned roadway is coming through and will cross over the end of the canal. There's a large concrete outlet structure surrounded by chain link which we're proposing to relocate. We'll build a new retaining wall at the edge of the roadway, relocate the structure basically in the same spot in the new canal. The buffer is pretty well developed and there's not a lot of solid buffer there. There's a temporary impact shown in order for the contractor to come in and replace the out let control structure. We have learned that DES considers that a small dam. We are going to be applying for a dam permit for the relocation of that as well. As part of the mitigation for dredge and fill, Dave McNamara said we've proposed to use the in lieu feet. The City has been talking to DES about potentially targeting that in lieu fee payment to the City's specific project fund as opposed to just going to the general fund. Nothing has been finalized yet. Commissioner Gallagher asked if the timing of the City, and called it a City ARM fund for lack of what it's officially going to be called, will that be up and running to accept the funds...Chris Sullivan said yes by the time they get ready to go. Commissioner Trivilino asked for a broad overview square foot idea of the total environmental impact for the whole project. Mr. McNamara said the jurisdictional wetland impacts are 28,826 square feet, or and about 5,000 square feet of temporary impacts. Within the various wetland buffers for the City, it's about 155,000 square feet. One other thing to note on additional benefits, Dave McNamara said the Fimbel Door site is a significant amount of impervious area out there. It will all get pulled out and some of it is being used for detention ponds but all of the concrete will be removed as part of the project. 5 Commissioner Trivilino asked if they'd have to do any toxic removal from the Fimbel site. Mr. McNamara said there is asbestos within the project corridor. That's being currently worked on with DES now, in terms of quantifying what's out there and trying to nail down how much there really is and then finding disposal sites. Mr. Sullivan said with these retention basins that you're building, you're going to be planting too as well with these. Mr. McNamara said yes. Commissioner Gallagher indicated that the City was before the Commission for the borings from the river crossing and they came back with additional requests. Do we know the findings of those? Was there any asbestos or toxic materials found within those borings? Mr. McNamara said of the first set of borings, only one found asbestos and we knew it was going to going in. There are a couple more from that group that haven't been done at the River Bridge area. I don't know on the second set if they've been out...Unidentified Male Speaker said the second set which Sanborn-Head is managing the effort to look at the asbestos and concerns underground with hazardous materials. The second set is really to get a better definition or limits of those asbestos areas that Dave mentioned before. They have the okay to go out and do the drilling. Since then, they've gotten the okay with their asbestos work plan with the State. They're scheduled to go out next Thursday on that last round. Commissioner Overby asked when the project was beginning. Are you going to start the project in different areas? Mr. McNamara said yes. There will be several construction contracts. The first construction contract is going to cover Broad Street, the northern section of the Parkway, the Baldwin Street Bridge and some amount of the work between Baldwin and Fairmount. This will advertise to get the work to start later in the summer. There will be a contract for the River Bridge. Another contract will cover the Fairmount Street Bridge and the remaining and the final contract will cover the Mill Yard area. They'll end up overlapping quite a bit. The starts will be staggered. Some of it is you can't build Baldwin and Fairmount bridges is together because of cutoff of access. We have to build the Baldwin Street Bridge first in order to take down the Fairmount Bridge. Commissioner Gillespie stated one of the items is invasive species. You have just Water Chestnut indicated. There's a lot of Bittersweet out there and Loosestrife as well. Anything to be done about some of the invasives along the route? Jamie said they have identified a few of their items out there whether they're tree species, shrubs or vines. That information will be part of the contractor's package. When they do go out there depending on the species, they may either have to take steps such as the in river plants to make sure their vehicles are clean prior to going in and coming out. The other species depending on what it is though, they'll ensure that those have been properly take care of. If we can avoid some of those sites or if we have cut them for access or whatever reason, they'll have to ensure that they're properly disposed of in the proper manner so they won't spread again. Commissioner Gillespie corrected an error on the dividing page. You have New Hampshire National Heritage. It's Natural Heritage. On the lot plan maps, you don't show where the location of where the Parkway goes. You're following mainly the railroad. How far away from that are you actually running - an inch, half inch? Mr. McNamara said it varies. It's not exactly parallel. It's generally 60 to 80 feet on the center line of the road/tracks. If you look at the aerial photograph, you have no idea where the roadway runs. Mr. McNamara said they could try and overlay something onto that area. Certainly the railroad tracks do show up in the plan used. We could see if we could get something on that aerial. Commissioner Gillespie indicated the roadway comes off the river toward the Mill Yard and is an elevated section. Eventually you drop down and become street level where the outlet is. Mr. McNamara said they were close to grade. They're a little bit high but for the most part, we're pretty close to being at grade. Commissioner Gillespie said the only impact on the canal itself would be constructing the new outlet. Dave McNamara said the roadway does impact the canal itself. 6 Commissioner Trivilino asked when the traffic comes down onto the Pine Street Extension is anything going to be done with the 4-way intersection where Central Street intersects Pine. Mr. McNamara said yes. There will be a signal at Central, Ledge and Pine Streets and there'll also be a signal at the Palm Street intersection. That will all be coordinated with the new signals that were recently put in. Commission Gillespie asked if there would be any sidewalks along the highway other than over the bridge. Dave McNamara said there will be sidewalks on both sides starting on the River Bridge through the Mill Yard. There will be sidewalks on Broad Street and tapering down as you get near the Dairy Queen area. On the Parkway, we're proposing a sidewalk on the west side for the entiretyly but that will go as a bid alternate depending on funding. To various degrees, we'll grade in the sidewalk platform. As part of the contract, the contractor will provide a price to put the concrete or paved sidewalk on that. If the funding is there, it will go in as part of the project. If not, at least it will be graded and set up so that in the future if the City wanted to come in and put a sidewalk in, there would be minimal impact. Commissioner Overby indicated there will be pedestrians on it. Commissioner Trivilino also said bicycles. Commissioner Gillespie asked if they had any idea how much the in lieu of fee we're talking about - ballpark figures. Jamison Paine said somewhere in the ballpark of $230,000 roughly. We've been working with DES on that. It includes both the wetland impacts, stream impacts and bank impacts. Commissioner Trivilino asked which streams are going to be affected. Unidentified Male Speaker said the only revering (no sense) areas would be the stream itself and the canal. In all honesty, Commissioner Trivilino said the buffer for most of the Parkway and along the river is a disaster right now. Between the Tannery, Fimbel, and lord knows what else has been there over a century. Commissioner Trivilino asked the Commission if they wanted a site walk. Commissioner Gillespie said he'd like to see the wetland that's going to be filled in. Commissioner Overby asked if there was an aerial on that particular site that you're going to be filling. Mr. McNamara said they have aerials on that. We do have some photos of it in the back. Commissioner Gillespie thought in some cases they should be getting credit for the buffer being moved or cleaned up. Unidentified Male Speaker said the water quality you'll see hopefully a substantial improvement with. There's a lot of impervious surface being removed. The proposed water treatment basins will be a win for the City. Commissioner Trivilino said the groundwater that isn't filtered through asbestos is probably better. Dave McNamara said a lot of it will be properly capped. Some if may not be properly capped now. Some of it will leave the site. There's probably not enough volume on site to recap it on here. It's not being cleaned up. Commissioner Gallagher asked if the wetland they were filling is in photo #7. Mr. McNamara said photos 4 and 5 is the one that's getting filled. Commission Gillespie asked about the outfall into the Nashua River along the bank. You said you were lettadng the outfall into another outfall. Dave McNamara said there's an existing outfall there. Basically we're going to replace the existing outfall. Commissioner Gillespie asked if it went all the way down the river's edge. Mr. McNamara said no but it will stoned outside of the outfall. Commissioner Gillespie asked if it went beyond the berm/flat spot that's there. Dave said no. Commissioner Trivilino asked the Commission if they could do this site walk on Monday too. The Commission agreed on Monday the 11th at 9:45 a.m. at the building that housed Outdoor Power. 7 Commissioner Gillespie said he'd like to see the approach to the bridge on the north side if we can get down to that big lot there. Commissioner Trivilino said this project has been very long in the making. The ultimate design that's been reached and as Commissioner Gillespie has pointed out, it does way more good than harm. Dave McNamara said there's significant reduction not just environmental but on almost any impact. Commissioner Trivilino said the riverbank along that stretch will no longer be an eyesore. F. Other Business and Updates: • Officer Elections Commissioner Gallagher asked what the plans were for officer elections. Commissioner Trivilino said she'd stay Acting Chair. Commissioner Gallagher said once they get a new member. Commissioner Trivilino said they only needed one duly appointed. She and Dick haven't been approved yet. She said she didn't count on being reappointed. Commissioner Overby asked if they've approached the Mayor about your reappointment. Commissioner Trivilino said no. Things need to be left to happen in their own good time. Chris Sullivan said the Personnel Committee is meeting on the 11th in order for them to interview candidates, they would have already had to have been appointed. The Mayor has to appoint them to the Board of Aldermen. The Board of Aldermen sends it to Personnel and Administrative Affairs. That Committee chooses whether or not to confirm the appointment. Once that takes place, they're it. It should be a matter of public record. G. NCC Correspondence and Communications Chris Sullivan indicated all they received is the Forest Notes Magazine. H. Informational Items: • Forest Notes, Winter 2013 I. Project Updates by Commissioners: None J. Non-Public Session K. Adjournment MOTION BY COMMISSIONER GALLAGHER, SECONDED BY COMMISSIONER GILLESPIE TO ADJOURN MOTION CARRIED 8