APPROVED
TOWN OF
PLANNING BOARD MEETING
Joint meeting with Board of
Adjustment and Conservation Commission
Planning
Board Chairman Peter McNamara called the meeting to order at
The Planning Board Secretary Paul Dadak called the Planning Board’s roll:
Planning Board:
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PRESENT: |
Peter McNamara, Roger Montbleau, Paul Dadak, Paddy Culbert, Tim Doherty, Jason Croteau, Selectmen Representative William McDevitt, Alternate Joseph Passamonte, Alternate Mike Sherman, Planning Director Jeff Gowan |
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ABSENT: |
None. |
Zoning Board of Adjustment:
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PRESENT: ABSENT: |
David Hennessey, Svetlana Paliy, Peter McNamara, Robert Molloy, Alternate Chris LaFrance, Planning Director/Zoning Administrator Jeff Gowan Kevin O’Sullivan, Alternate Bill Kearney, Alternate Lance Ouellette |
Conservation Commission:
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PRESENT: ABSENT: |
Paul Gagnon, Karen Mackay, Paul Dadak, Glennie Edwards, Chris McCarron Heidi Ramich, Lisa Loosigian |
JOINT CASE (Planning Board, Zoning Board of Adjustment and Conservation Commission)
Planning Board Case # PL2011-00017 // Board of Adjustment Case #ZO2011-0025
Map 22 Lot 8-138 - SOUTHERN NEW HAMPSHIRE MEDICAL CENTER – 33
Windham Road – Seeking from the Board of Adjustment a Variance concerning
Article III Section 307-12 of the Zoning Ordinance to permit construction of a
medical office building with a rear setback of 48ft. where 2x the height of the
building is required and a Variance concerning Article VII Section 307-39 of
the Zoning Ordinance to allow a portion of the entrance drive and the corner of
one parking space to encroach into the Wetland Conservation District.
Also seeking a Site Plan
Review from the Planning Board of the proposed 8900SF medical office building
and a Special Permit for the encroachment into the Wetland Conservation
District.
Mr. McNamara opened the joint hearing.
Mr. Dadak read the list of abutters aloud. There were no persons present who did not have their name read, or who had difficulty with notification.
Mr. McNamara explained the process that would be taken during the joint hearing.
Planning Board Hearing:
The applicant’s representatives. Mr. Robert Clarke of Allen & Major Associates, Inc., Mr. Dennis Mires of The Architects, and Mr. Scott Cote Vice President Facilities and Emergency Management for Southern New Hampshire Medical Center came forward to review the submitted requests. Mr. Clarke reviewed the submitted site plan. They proposed two access points for the parcel. Approximately ten waivers were being requested along with a variance dealing with the rear yard setback. There may possibly be a variance request for parking within the Wetland Conservation District (‘WCD’), however it may be eliminated once discussion occurs. Mr. Clarke indicated they met with the Pelham Fire Department, who requested an 18ft. wide level area; this area may be reconfigured so as to not require the variance for parking. The proposed medical office building was approximately 8900SF containing sixty parking spaces.
The architect, Dennis Mires came
forward and outlined a few of the projects they had completed in the recent
past with
Mr. Clarke mentioned that the
schedule was extremely aggressive and they would like to move forward as soon
as possible, breaking ground this fall.
He said this was one of the reasons they wanted to re-look at the planning
and the design and remove as many requests/reliefs as possible. He said the same approach was taken with the
recent bank (Enterprise Bank across from
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MOTION: |
(Doherty/Dadak) To accept the
plan for consideration. |
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VOTE: |
(7-0-0) The
motion carried. |
Mr. McNamara noticed within the traffic report that a recommendation was given for minor changes in the driveways. Mr. Clarke stated they accommodated/changed the two items the subconsultant mentioned; the radii on the curb cuts previously didn’t project out beyond the property line, and the radii on both the entrance/exits was increased. The only state permits required were the subsurface and curb cut. The applicant has applied to the New Hampshire Department of Transportation (‘DOT). They were currently in the review process with the Town’s Deputy Health Officer (Paul Zarnowski) for the subsurface; once comments were satisfied, they will submit for state approval. Mr. McNamara asked for a summary of the landscaping proposal and explanation of the neighbor’s buffering. Mr. Clarke stated that the site recently received a variance for use of a medical office; along with that variance was a request for screening. He reviewed the plan and showed the proposed plantings.
Mr. McNamara questioned how many
employees were envisioned being in the building. Mr. Cote discussed the proposed programs for
the building; (three) general family practice providers office, rotation of
specialists through the office (
Mr. Culbert commented that the hospital historically overbooked (multiple patients scheduled for the same time slot) doctor’s visits and questioned if the facility in Pelham would also do it. Mr. Cote said overbooking wasn’t something that they normally saw happening. He said the needs of a visit drove how long a provider spent with a patient. He noted historically providers wanted to make sure they had enough time with their patients. Mr. Culbert asked if the staff parking (18 spaces) was included in the proposed sixty spaces. Mr. Cote answered yes; he anticipated eighteen spaces for patient traffic, eighteen spaces for staff, which would leave twenty four spaces. Mr. Culbert asked again if they overbooked. Mr. Cote replied that they didn’t overbook but added that providers may run behind.
Mr. McNamara asked if all the
employees would be employees of the hospital.
Mr. Cote said they would be employees of the Southern New Hampshire
Health System, which is made up of the
Mr. Croteau asked for the hours
of operation. Mr. Cote stated that the
provider office would operate Monday-Friday
Mr. McNamara deferred public comment until the Planning Board returned. He invited Mr. Keach to come forward and provide comments.
Steve Keach of Keach-Nordstrom (Board’s engineering review firm) came forward. He said the Board was provided with his initial report, to which there was not a lot of substance in terms of comments that he believed could be addressed by Mr. Clarke. He said during the Board of Adjustment meeting there was a stipulation relative to a finding that the Planning Board needed to make. He then spoke to the parking waiver. As a point of comparison, Mr. Keach said he took the opportunity to compare the level of the proposed parking (1 space per 150ft. gross floor area) to other municipalities he had worked with. He felt the sixty spaces being proposed was more than adequate and was not opposed to the Board granting a waiver (for the number of parking spaces). Mr. Keach then discussed drainage. He said through the twenty five year design frequency storm the proposed drainage was a zero discharge system. The system was comprised of a series of storm drains capturing the storm water and directing it (by underground piping) to a combination infiltration/detention system situated south of the proposed building under the parking lot. The design engineer was taking advantage of the excellent drained soils that exist at the location. The test pit data demonstrates that the soil conditions assuming are real and the assumed water table conditions are real. Mr. Keach said it was a well designed system that would have zero discharge, through a twenty five year return frequency storm, to the wetland to the north. There was an overflow pipe (emergency flow) that provided a discharge of approximately .18 cubic feet per second (similar to a two inch garden hose) in a one hundred year storm. Mr. Keach was very comfortable with the proposed system. He said it created a decrease in post-development peak discharge to adjoining properties (including the street).
Mr. McNamara recessed the Planning Board hearing.
Conservation Commission Hearing:
The Conservation Commission came forward to conduct their hearing. (* see Attachment A – Conservation Commission meeting minutes)
Zoning Board of Adjustment Hearing:
Zoning Board of Adjustment
Chairman called the meeting to order at approximately
Secretary Robert Molloy called roll.
Mr. Hennessey appointed Mr. LaFrance as a voting member. He stated the Board would rely upon the abutter’s list read aloud by the Planning Board. He asked if anyone was present who didn’t have their name read as an abutter, or who was improperly noticed on the hearing. No one came forward. Mr. Hennessey stated that the presentation the Board previously heard would suffice as a general outline of the case before them. He understood that the applicant would like to make a change in the application for the Zoning Variance. He asked the applicant to address their request.
The applicant’s representatives. Mr. Robert Clarke of Allen & Major Associates, Inc., Mr. Dennis Mires of The Architects, and Mr. Scott Cote Vice President Facilities and Emergency Management for Southern New Hampshire Medical Center presented the variance request to the Board. Mr. Clarke explained that they had originally requested two variances, however they would like to withdraw the variance request to Section 307-40b – work within the WCD buffer zone and for the use within the WCD. They would still like the Board to consider a variance to Section 307-12- rear yard setback to 2x building height (30ft. minimum required).
Mr. Hennessey asked that the applicant review the variance criteria. He noted that the applicant didn’t need to run through the whole presentation as the Board had been in the audience listening to the other hearings. The public would later be asked for comment. Mr. Hennessey noted that all the members of the Board had previously walked the site.
Mr. Clarke discussed the building height. He said the mean average height of the building was 24ft., which would require three times the height for the front yard setback and two times the height from the side and rear setback. He was able to comply with the sides and front, but didn’t comply with the rear setback being two times 24ft., however they did comply with the 30ft. minimum. Mr. Clarke told the Board they were requesting a waiver for the number of parking spaces; 94 spaces were required. He said for proper site circulation of emergency vehicles, vehicular traffic and pedestrian made it so the building envelope was confined to the proposed location.
Mr. Clarke proceeded to read the variance criteria into the record, as submitted with the variance application.
Mr. Hennessey read aloud the
variance conditions for approval (Case#2447 –
PUBLIC INPUT
Mr. Mike McCoy, 8
Mr. Hennessey discussed the hearing and public input process.
Mr. McCoy wanted to know when he would have input regarding the screening for his property. He requested a chain link fence along with greenery. He showed the Board the location of his home. Mr. Hennessey told Mr. McCoy that he could speak to the Planning Board during their site plan review (later in the meeting). Mr. McCoy was concerned once the building was constructed, absent a fence, that his lot would be accessed by motorcycles, dirt bikes etc. Mr. Clarke noted that Mr. McCoy’s property was located beyond the abutting Town owned land approximately ¼ mile from the applicant’s parcel. Mr. McCoy was not a direct abutter. Mr. Hennessey felt the question was better suited for the Planning Board to handle.
Mr. David Hazlewood,
Mr. Hennessey said there was wording contained in the previous variance approval that stipulated “…a buffer between the new building and the abutting residential property (Hazlewood’s property) shall be constructed to the abutter’s satisfaction”. He asked if that wording sufficed for Mr. Hazlewood. Mr. Hazlewood answered yes. He wanted to maintain his privacy being in a residential area. He asked that the Board consider the hours of operation since the business was within a residential area. He questioned if the hospital would conduct additional business such as clinics etc.
Ms. Lisa Landry, resident came forward to speak regarding the proposed medical facility. She spoke favorably of the facility and the employees. She said the facilities were very clean and kept up well. The outlook on the community was high standing.
Ms. Glennie Edwards, resident came forward and informed that Pelham didn’t have a historic district. She said the abutter (Mr. Hazlewood) purchased his property across the street from the American Legion. She noted that the Legion hall had the occasion to be rented out for functions and have a flow of traffic to and from the site. She commented she wouldn’t have an argument legally or otherwise if the Board had a case before them for a medical facility across from her street. Ms. Edwards discussed the proposed berm and said she believed the applicant would use the best landscapers that they knew of. As a Town resident, she would like to see the facility go in because the Town lacked similar facilities.
Mr. Cote said their obligation to
the Hazlewoods was to satisfy their needs even if it meant having a 7ft.-10ft.
Arbor Vitas. They had a long history of
maintaining their facilities; if any of the plantings died they would have an
obligation to replace them. Mr. Cote
discussed the hours of operation. The primary provider office practice would
operate Monday-Friday
Mr. Hennessey was familiar with
the facility in
Mr. Hennessey closed the public portion of the hearing. He commented that the Town didn’t have a historical district. He said the Town had a Historical Commission that everyone had forgotten about. There was possibly work going on to have a historical district on the ballot (in March). Mr. Hennessey said testimony was correct that it was a residential area; a use Variance was previously granted (November, 2010) on the basis of the Simplex decision of what was already in place in the area. He discussed the stipulations contained within the previous variance and asked if the Board would like to suggest alternative language. The Board didn’t amend the previous stipulation or add any stipulations. It was noted that a site walk was previously conducted. Mr. Hennessey noted he had previously voted against the variance having difficulties with the parking and proximity to the Town center, but felt the proposed was an improvement over the previous plan and was far more definitive. He will be voting in favor of the proposal.
Mr. McNamara noted that the previous plan was for a 15,000SF building, which had now been reduced considerably.
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BALLOT VOTE: |
Mr. Hennessey – Yes to all criteria Ms. Paliy – Yes to all criteria Mr. McNamara – Yes to all criteria Mr. Molloy – Yes to all criteria Mr. LaFrance – Yes to all criteria |
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VOTE: |
(5-0-0) The motion carried. |
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VARIANCE APPROVED
The Zoning Board of Adjustment adjourned their hearing.
The Planning Board re-opened their hearing.
Mr. Gowan commented regarding the abutter (Mr. Hazlewood) being satisfied; the standing variance was that the abutter had to be satisfied. He said he knew from Mr. Cote and his team that they would work, and would continue to work to satisfy reasonable requests for buffering. He said when the Board was ready to make a decision he would put together a draft Notice of Decision. And in that Notice of Decision he would suggest that whatever buffer was decided upon, it would be not only constructed but also maintained. Mr. Gowan discussed the proposed project in the context of the round about that would be constructed (late 2012-2013 by the state). He said the proposed project, with the current conditions according to the peer review consultant, is safe from a standpoint of sight distance. He commented that the proposed project would be even more safe with the round abouts in place; the approach to the round about closest to the project will be marked at a 20mph speed limit. Also coming from the round about to the proposed project traffic will have been at a 20mph speed condition, so they will just begin to gain speed past the site.
Mr. McNamara asked if the
applicant had any plans to put in a CT or MRI unit or anything that would
generate a significant amount of noise or smoke. Mr. Cote answered no; it was just a simple
flat beat x-ray unit. Mr. McNamara
questioned if there was a state permitting process to add something
questionable, such as a methadone clinic.
Mr. Cote noted that they didn’t support methadone clinics. He said the immediate care clinic required
them to have state licensing. He said
additional programs (collective group programs) occurred at the main campus in
Mr. Dadak asked if the facility was required to have a permit from the state for their medical waste. Mr. Cote said they would have normal activity (i.e. sharps, containers, bandages), all of which would be contained within the facility and would be picked up weekly by a medical waste disposal contractor. They don’t allow any of that material to be outside of the building; it would be locked and secured within the building.
Mr. McNamara believed there was a discussion regarding the handicap spaces, or an abbreviation of them. Mr. Clarke stated the requirement was to have one van accessible space along with a painted (8ft wide) island next to that space. He pointed out on the plan where the 8ft. accessible pathway was located. There was another marked pathway that could be reduced to 5ft. wide.
The Board addressed the submitted waiver requests. Mr. McNamara read each one aloud as well as the explanation as to why they were needed.
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MOTION: |
(Croteau/Dadak) To accept, for
consideration, the waiver request to Article IV, Section 248-39 – no site
improvements within 25ft. of the wetland.
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VOTE: |
(7-0-0) The
motion carried. |
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Mr. Clarke commented that they didn’t need the variance for the parking space, but they slightly encroached with the corner of the drive isle. Mr. Cote stated he wouldn’t be opposed to eliminating two more parking spaces, if the Board would be in favor of such. He was confident that 58 parking spaces would be more than enough. Mr. McNamara said the Board would take the testimony as an amendment to the plan; there will now be 58 parking spaces.
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MOTION: |
(Croteau/Doherty) To accept,
for consideration, the waiver request to Article IV, Section 248-31 – no site
improvements within 50ft. of a wetland. |
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VOTE: |
(7-0-0) The
motion carried. |
----------------------------------------------------
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MOTION: |
(Croteau/Doherty) To accept,
for consideration, the waiver request to Article IV, Section 248-31 – rear
setback being 2x height of the building; 30ft. minimum. |
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VOTE: |
(7-0-0) The
motion carried. |
---------------------------------------------------
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MOTION: |
(Croteau/Montbleau) To accept,
for consideration, the waiver request to Article IV, Section 248-32 – parking one per one hundred
square feet, plus one half employees, plus one per two employees. |
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VOTE: |
(7-0-0) The
motion carried. |
----------------------------------------------------
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MOTION: |
(Doherty/Montbleau) To accept,
for consideration, the waiver request to Article IV, Section 248-32,D – no parking spaces over or within 25ft. of any leach
field. |
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VOTE: |
(7-0-0) The
motion carried. |
---------------------------------------------------
Mr. Clarke noted there was an existing well on site they were looking to utilize for their irrigation.
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MOTION: |
(Croteau/Dadak) To accept, for
consideration, the waiver request to Article IV, Section 248-41,E – septic tank 100ft. setback from the well. |
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VOTE: |
(7-0-0) The
motion carried. |
----------------------------------------------------
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MOTION: |
(Dadak/Montbleau) To accept,
for consideration, the waiver request to Article IV, Section 248-41,E – leach field 100ft. setback from well. |
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VOTE: |
(7-0-0) The
motion carried. |
---------------------------------------------------
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MOTION: |
(Montbleau/Doherty) To accept,
for consideration, the waiver request to Article IV, Section 248-41,E – leach field 50ft. setback from lot lines. |
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VOTE: |
(7-0-0) The
motion carried. |
----------------------------------------------------
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MOTION: |
(Montbleau/Culbert) To accept,
for consideration, the waiver request to Article IV, Section 248-41,E – sewer lines 75ft. from
well. |
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VOTE: |
(7-0-0) The
motion carried. |
----------------------------------------------------
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MOTION: |
(Montbleau/Doherty) To accept,
for consideration, the waiver request to Article IV, Section 248-41,E,2 – sewer lines 20ft. from lot lines; no leach field or
bed shall be located under or within 25ft. of any concrete or bituminous
concrete surface covering. |
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VOTE: |
(7-0-0) The
motion carried. |
----------------------------------------------------
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MOTION: |
(Culbert/Croteau) To accept,
for consideration, the Special Permit, Article III, Section 307-40,A&B – for work within 50ft. buffer of the Wetland
Conservation District. |
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VOTE: |
(7-0-0) The
motion carried. |
Mr. McDevitt wanted it on the record, that his preference was for the applicant to have a discussion with Mr. McCoy about his concerns for the buffering at the rear of the property prior to the Board granting final approval on the project. He suggested that the Board consider restricting hours of operation. He said it was granted a variance, but it was primarily a residential neighborhood. He then referred to the Keach-Nordstrom letter (and read a portion of which loud) relative to the exterior of the structure/design. He commented that testimony was given that the building would be consistent with the applicant’s corporate design, but noted there was a stipulation that required the applicant to demonstrate that the building would be consistent with other architecture in the area. He needed to hear that from the applicant. Mr. McDevitt then addressed the question of noise. He said the Town didn’t have a noise ordinance and unless there was really a disturbance of peace, there was no way to deal with noise except when dealing with a plan at the Planning Board.
Mr. McNamara asked the applicant what would generate a significant amount of noise in the proposal. Mr. Cote couldn’t think of anything, other than the vehicles coming and going from the site. He said the first ones to complain about noise was the providers from the offices themselves. The only other thing Mr. Cote could think of is possibly if they decided to have an emergency generator at the site in the event there was power loss. He said they could get cabinets to enclose a generator to keep it as quiet as it could be. He noted that the HVAC equipment was located within the building and had sound attenuation on it. Mr. McDevitt said his concern was not from normal noise coming from a building, but rather something like an MRI unit. Mr. Cote said the only thing that came to mind was when they would pick up the dumpster and recycling because that would have a truck coming on site. He noted they didn’t have large trucks coming to the site, it was usually a medical van and occasionally a UPS size truck during normal business hours. He said he promised the Hazlewoods that he would control when the dumpsters were picked up. He stated he couldn’t control snow removal. Mr. Cote was sure Mr. McCoy’s concern regarding the buffering could be addressed. He noted that Mr. McCoy’s property was separated by the public land and was told by the site engineer that it was nearly a quarter mile away, so it might be a stretch for them. He didn’t have a problem restricting the hours of operation to the hours he told the Board. He said they wanted the community to be proud to have them in it. At some time if they determined it made more sense, based on community demand to have more hours, they would like the opportunity to come back and discuss it with the Board. With regard to the exterior of the structure Mr. Cote felt their team had done a good job in meeting the spirit and intent of what was suggested to be done. He believed with the finish details the Town would be proud to have them in the community.
Mr. McNamara recalled seeing a note in one of the reports regarding keeping the vegetation around the driveways cut/trimmed. He asked if that area was in the public right-of-way or the applicant’s property. Mr. Clarke reviewed the landscaping plan and commented that the plantings were pulled back from the street. He said the Town’s Highway Department would typically cut anything in that front zone. Mr. Cote discussed the existing stone wall. He said it was suggested at a recent meeting that they may want to consider moving the stone from the center of the property and placing it up front toward the proposed tree line. He thought it would be an easy thing to do and was good idea. Moving it would maintain the character seen throughout the community.
Mr. McNamara asked if provisions were made for snow storage on the plan. Mr. Clarke answered yes. He showed the proposed location as being along the front and to the south side of the property. There was no snow storage proposed along the WCD.
Mr. Culbert asked how many
parking spaces
Mr. Doherty asked Mr. Keach if he felt 24ft. in the entrance (in front of the island) was adequate for emergency vehicles to access the site. Mr. Keach replied that he put a template on the site plan (for a single unit) and found that the site had adequate circulation for that function. The area that concerned him was the sharp elbow to the left of the northerly entrance. In order for a larger vehicle to make that turning movement, it would encroach on both lanes of the parking isle. Mr. Clarke informed that the Fire Department had them put an 18ft. wide access point along the side of the building. In the event of an emergency, a vehicle would have the ability to pull straight in and park.
Mr. Sherman had concerns with
drainage and flooding south of the applicant’s parcel and questioned what
designated a 100-year storm event (how many inches of rain). Mr. Keach stated that a hundred year storm
and a hundred year flood were two separate and distinct hydrological
events. The data provided by the US
Weather Bureau, for a hundred year storm in this region, suggests it is 6.3
inches of rainfall in any given 24-hour period (not necessarily in a 24-hour
calendar period). Mr. Keach said in this
site plan review application, the applicant’s consultant did drainage analysis
for a family of storm events (2-year, 10-year, 25-year return frequency storms
and did a check for the 50- and 100-year storm). He said keeping with the 25-year return
frequency event, the infiltration system had enough storage capacity and was
functioning in detention mode (had adequate volume for storage) while it slowly
leached out. He said there was adequate
storage capacity to hold all the water (with no overflow) for the whole
duration of a 25-year return frequency design storm event. Mr. Keach noted there was an overflow that
ran along (and parallel) to the westerly property line from the system that had
a discharge point adjacent to a wetland situated within the WCD at the
northwest corner of the site. That was the
only possible discharge point of the storm water management system; this
affectively serves as emergency overflow for storms at/beyond the 50-year
return frequency. The measure of
rainfall somewhere between the 25- and 50-year frequency storm the system would
surcharge and water would discharge at that point. The maximum is .1cubic feet per second in a
100-year event; this was equal to approximately 1.5 gallons per second,
equating to about a two inch fire hose.
Mr. Keach reported that he was satisfied that the system and storm water
management provisions of the site in general were more than adequate and
complied with the local requirements and site plan review regulations. He noted it would create a reduction in
runoff during all storm events to adjacent properties, including
Mr. McNamara informed that the Board would incorporate all testimony heard during the Conservation Commission and Zoning Board of Adjustment hearings into their meeting minutes.
PUBLIC INPUT
Lisa Landry, Chairwoman of Pelham Economic Development came forward to speak on behalf of the committee. She thanked the various boards for conducting a joint hearing. She felt the proposed business would benefit and be a great asset to the Town.
Ms. Glennie Edwards,
Mr. Mike McCoy, 8
Mr. David Hazlewood,
The Board did not feel the need for a site walk. Mr. McDevitt had the permission of the applicant to walk/review the site. Mr. Cote asked that people be very careful around the existing structure. The Planning Board did not schedule an official site walk.
The plan was date specified to
Joint Meeting adjourned.
ATTACHMENT A
Joint Planning Board, Zoning Board of Adjustment and
6
Village Green
Conservation Commission
Meeting Minutes
MEETING OF
Members Present: Absent:
Paul Gagnon, Karen Mackay, Heidi Ramich, Lisa Loosigian
Paul Dadak, Chris McCarron,
Glennie Edwards
The Conservation Commission
portion of the meeting began at
NEW BUSINESS:
Map 22
Presentation by Robert Clarke
of Allen & Major Associates, Inc., Dennis Mires of The Architects, and
Scott Cote of Southern NH Medical Center
The proposal is to construct an 8,900 square foot medical office building. There will be no wetland impacts on this project. The WCD impact will be 1,600 square feet. The impacts to the WCD will be for the installation of a drainage pipe, the construction of a portion of the entrance drive and grading toward the wetland on the north side of the site. The wetland has been flagged by Gove Environmental.
The site distance north and south
on
The wetland is located in the northern portion of the site. Initially, the plans showed a parking space and part of the walkway within the WCD. This condition required a variance from ZBA. The engineers have since adjusted the plan. The parking space has been moved to the southern side of the site and the walkway has been reduced in length. The revised plan design does not require a variance for WCD infringement. The WCD is still impacted by a portion of the entrance driveway, but this condition requires a special permit from Planning and no action from ZBA.
Three of 4 test pits on site showed no evidence of seasonal high water table. One test pit showed damp soil, though soil moisture was 8 feet down. Soils on this site are excellent for drainage.
The drainage system is a 450I
Stormceptor infiltration/detention system. The system will be located on the
southern end of the site under the parking lot. The system is designed to
remove 80 percent of total suspended solids (
The infiltration part of the system consists of ‘bee hive’ arc type chambers 30 inches high. The system is delivered in 4 foot sections that are linked together when they are installed. Water can pass between the chambers. There will be 5 rows of chambers. Water will enter the most southern row first. This row is the isolator row and is used to trap silt, suspended in the runoff. The chamber areas sit on a 6 inch bed of crushed stone.
An overflow pipe exits the system to the south-west corner of the lot, the pipe runs along the south side of the lot and empties into the wetland on the north-west corner of the lot. The outlet to the drainage pipe is 5 feet from the wetland. This location is necessary because of the slope of the land and the elevation of the drainage system. In order to pull the pipe farther away from the wetland, the discharge of water would be higher up the slope which would cause erosion of the slope. The overflow pipe will empty .18 cubic feet per second in a 100 year storm event.
Steve Keach said this is a well engineered plan that he supports. The applicant has complied with all local drainage requirements.
There is a maintenance plan to
care for the infiltration/detention system. Inspections of the system will be
done every spring and fall and an annual report will be sent to Planning. The
man holes will be opened and the system inspected. If silt is clogging up the
system, water will be jetted into the isolator row chamber and then vacuumed
out at the opposite man hole. The waste water will be
removed from the site.
The slopes in the WCD on the north side of the property will be 3:1. Mr. Keach recommends the 3:1 slope rather than a retaining wall because a retaining wall requires periodic maintenance and will impact more of the WCD. No water will be coming off the parking area down this slope so chances of erosion are low. The 3:1 slope roughly approximates the current conditions on the site. Mr. Keach would like to see the slope seeded with a wildflower mix and be allowed to revert back to natural vegetation. He does not anticipate mowing and landscaping of this area. The 3:1 slope will level off about 5-10 feet from the wetland.
The installation of the drainage pipe behind the building will require about a 20 foot wide clearing. Currently, shrubs and trees are growing in this area. After pipe installation, the area will be seeded with grasses. Over time native species will seed into the cleared area.
The Conservation Commission’s
portion of the meeting ended at
Respectfully submitted,
Karen Mackay,
Recording Secretary