HomeMy WebLinkAbout2000-02-24 Engineer Review (2) C.'-.'J"0L -ERI
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C'J"OL ANTnNIO
EINGINEERO ANOSCIPEN I IFS F F5
Novernbt�r 5, J 9919
Heidi Gl-iffiTl
PhInniTIg Board
15 School Street
North A ndover, MA 0 184 5
RF- Fingi-rieerin,g Review
Lo.9 Willmx Strect
Proposed OffiCe SUbdivision
Dew-Ms, Gyri ffin.,
.In response to your request, Coler & C ohmitonio, In:c. has reviewed the subm..11tal I-xickage
for theabove rtferenced site, In mkbfiioll�, we have visAed the- sjge lo obs'erviv; field
c,olidilions ()Ti Oo,,oher 25, 19991, The project hliN I)eun revieweld Nm, to, the
llecjuireryllcnt� of the "Zoning By-Law f0l' Site Ph.M Review and Special 111crniit" in Noilli
Andover as well as standard enginceiing pi-actice., I"he subiiiittal package inCILtClect the
followi rig in forniation:
Ph,ms Entitled::
"Propo-sed, Site Development, Willow Streo, Nur[h An(h,wet" location
IP
described as Map 98D-1 AA 52 coTISiMing ol'ten �.;,hccls dated 10115/19,9,
Prepared by MHF Design Consultants, ]Tic.
Reports,Entitled
"S I o un w al er Maiiiage men t R epoi-1 foi-Pi-i i�po,�ed 0 ffi ce B u 11 d 1 n g, Pi-oJec L
Wffllov, trcct, North An:dover, NIA", date0l, 10/14/99, Prcparccl by MILL
Design Consultatits, Inc.-
The site k locwed wil hin the N(,m-,t.fT Andovei-Bminess Park, More ",,,pecl Flea]ly it is
located on r o,uthwesls,iide of Willow Stre�ct, identified by the'"Fown Ass,cssor's, Maps, as,
Lot 52 on Map 98D. 'nic proposcid site is currently undevelopcull and contains
approximately 2 acres, The proposed development includes a 2-story office building with
a gross floor area of 7,344 sf, andassocialed drivieway/parking area, laii&s,a~iping, fighifiig,
utiblies and dl-ainag� racilifies,
We o ff'6-the fol I owi n g co rn,mcT i ts'.
777777777=77 =7 7=7 7777
10 1 Amoirdl Park Drive 781-982-5400
Norwe I I, MA 02,061-1 85 Fax". 781-982-5490
ZONING BYLAW
1, Section 6a.I it is unclear if any new signs have been proposed.
2. Section 7,I),l Tt is uncicar if the properly is ,,uhject to the C:o€itigtiow, Buildable
Area (CI A) cnitoiia. The by-law states at least sevc€ity five (75) percent of tlic
minimum Iot arca rcquired for zo nirig shall be conti gip ous land other t11an land
Ioca(ed within a lime i(en€ified a� wetlynd resource, arews in accot-dance with the
Wetlands T'rotec#ioji -Bylaw-
1 Section 7-3) 11 is our understandirng a vzat ia€acc was granted from the rC-quircd
50' Fi-o nt sctback. The propowd st t€aack is 0',
4- Section 7k) The Required Lot sectioTi of the; Application for Site Flan review
should he modificd. The Floor Area Rado should i-ead 0.50:1- Tt cLn-rently reads
5 Sect€o€-3 8.3)5-)c- The puns aivc clot si gut!d by the: Pi-Ofessl0€naI Engiueen--
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i6, Section 8,3)5.)e.)iv.) Ilo legal tmumhi-a€ices as they may ITZ!late to the sites
phyMcal devclopment have been listed.
j7. Scction 8, } ,)e, v-} The, pi-oposed 238 4�:owour on thu- west side of the delen[10V
basin has bn !e-n clmwn incoi-meetly. The grade -*oij1d be shown as a closed loop,
8, -cEio on S.3)5)c. vj. It is Lim:Ieal, iF Nigrns air- proposed fm- the site. No
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information has been kjbmiILed for i'cvie ,
9. Section 8.3)5-}e.}vii,} S1'C)RMWA'FFR DRATNAGE
Sce al-ai€cage cc i �xrers�s h lc� v.
10 Section 8-3)5.)c.)ix.) Ext(-,rioi- buikhng elevations Dave not bet-Ti .ubmitted with
this review ackage,
}
1 I Section 8.3) i-) The,wctl and line is sliow-fl ov tho pia€ , Wetland flag
nunibers should lac labeled an the plan€;, A Notice of Intent Applic:Llion s}non€ld lac
fiIt-d in conjunction with this application. It should also be noIt! i that Mosquito
Brook is a river front area as hown pan tiic North A€ dove-We11ands Rcgulations
ivcrfront Area Maps (Figure 1 of 3). It appeals that the site rnaybc su ect to
The Rinfers Act. This may have a significant iwpa(:t oll the site design.
12. Section S.3)5)c)x ij. It is unclear if a sign is proposed for thv site, If a sign is
proposed, the iocadon ,hould €ae shown on the prams with sign di€r1esisionS
13. Section 8-3)5.)c.)xiii.)Dist�inces to ill tho noaivst roadways and/or cui-h cuts shall
be she} n for both sides of any stFeet which is ad-j ace nt I the i-ite-
4. Section 8.3 S. e.)xiv,)Tt is uncIear it outdoor storagelclisplay areas ave proposed.
i1-these areas are proposed, they shouId be shown curl the plans.
}5- Section 8,3)5,)e-)xvi,)I'lic location and detail oI-refuse areas shollId be 'Jlow n on
the plans. All vcfusc areas musl be fully enclosed.
16, Section 5.3)5.)e.) Q-) The lighting fixtures have been ,khown and detailed. The,
proposed ill u inatiora dincction and degree of illrtrr7ination have not been shove n
17, ectlon 8,3)5.)e.)xvii,) Drainage Bali n Study
See drainage crrmmuts below
18. Section 8.3)5.)e. xix.) A traFI-ic uudy in ay be s,=qu fired by the PIar njng Board,
19. Section 8.3)5-)e,.)xxi-)A chininey connec lion detail should Inc added I the detai
sheets foi- the s�we- conection iDIQ the uxisIiTIg 8" SC%Ver I-Mlin i11 WiI10W S(I'cct.
The invert labeled for the sewer invert appears to be prior to the chimney
(xn Flee(ion. 'Phis sh old d be cIanI'led.
2.0- Section 8.3 . e.}xxii-) A fiscal impact study may he re.clucs(cd by the PIfmping
Board.
21. Section 8.3)5.)c).x xi A,) A curnmLmity i mpact study mnt y be reclueqcd by the
PIanning Board.
23. Section 8.3)6-)a.)ii.)f.) The grading, drainage and erosion control p4m �lhould
snr>u+ talc location of control iiacasm-cs and a cdesQdp ic>n c 1 trtosc
171�aSk3I'CS.
Dl-airfa {C1171FIZBZ1iS
The,cxisting site appear, tip he w ithin a FLMA FJoo d Zone A On past 1)tMews
hicluding the Stop & Shop and 74U'1_umpike, the 100-}scar floors elevaticrTr at Lhe
south side, «F Turnpi€ce Stm-,t was determine l to be elevation 238 based tin local
observations. The Stop & Shop project is located downstri t!mn fiuom Willow
ti-eet 1i-om this site and 740 Tkimpike, Stmct is downstream �Icrws Turnpike
Street from Stop & Shop- Typically as one, goes upslrt,-ayn, the Hood elevation
increases.
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The I00-year flood clevation on-site is likely above cIcvation 238. Bast-d can this
el ovation t1}c flood water l"vom Mosc,gaito Brook may resiplt in backwater impaeis
into the detention basin causing possiNc flood problems can and ofI-sile-
Compensatory flood stoi-age rttay be rcquired to imp lemrent the flan, This issuc
should be addres,,ed-
ThiI vainage ca]cuIations use the uutlet s#nwtuve adjacent to Willow ,Sti-eet as a
dle'ign paint in (lie hydrologic inude,], The dralnagc avcas should be mudified Lo
reflect the existing topography 4nd riot be limited by the propeny iiiie-
It is unclear how the exisiing condition curve nut7 Nv% were oc;tahli shed. Based
upon ou site visit, the woods appeu to Dave a cover dcseii bed as good. The
ood.,� air- mostly located xithin (he wetlands and the curve number documented
jn anar-ndments t,T -55 is 79 1or wood wetlands, The, brush is desci7bed as faii-
condition and located in wetlands in the calculations- The, hi-rjsh appears to be in
flair etmdition, 11O cvcr, this area is tip)4nd- Tiro cxishng condition calculations
should be i-evised to reflect €ht- Qon-ect euii vc n uinbeis. The Cw-ve nkimher
dcscribing the brush/wetland cover typo for proposed condifions rs 48, The curve
nuinbf r fog- a sirnilai•cover type foi- existing con diI ions is listed as 70, The
props>�ed conditions cui,ve number should be me defiled consistent with exiting
condi11ovs for unaIton-A areeas.
The`l'imc of Concen#ralioil c ale ulatIon for existing conditions cites not appcar
rcfIcct field condiIium, The €lo w path s h ow n on the N-e-Developrrront Hydrology
plan appears (o be longcr than 450 feet. The, existing ditch should also be
inQ]ijdl-d in time TirTIC of COtICc�Itratio1i ealclllaliODS-
The hydrology niodcl appew-s to repute subcatchrjjcnt 5 illtu the slVtent 0T1
basin. Based upon the Poet-De�ve;loprncnt Hydi-oiogy Plan, 5 does
not appear to flow into the detention basin.
The roof drain pipe appffars to have app rox i in ately .5 feet of cover-
Documentatxtu should he suhmittcd on the pipe to assure the pipe has adequate
strength for this dcpth of cover. This pipe may be suhje-a to 1-mst Heaves in the
parking lot and be a long teri main#enarice c or3com,
The Stormwater Iv 4nagerment Report states the BI €V's will Ternnve: approx iinately
80 of the TSS. It is uncle;ai- how this is determined. The applicable `)~SS
remuval spreadsheet should be submittu-d. The rep)rt states the sediment forebay
ale,,rgn is ineIudcd in Appendix E. This ini-OT-MatlOn has not been ijlcludi Cd. The
s;cdimcnt forcbay should be de�igrje;d M accovdaiiec with the DEP loi-m ,rater
Management Policy,
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Tt Is uncleav if#lic dcfcntion ba in has the rf'quli-ed watci- quahty volume below the.
i1ivc11 out. 1fie recl4lired water duality volunic and the volujne providiM shr kdd be
submitted.
Based can test pit number 3, mottling occurs at approxima#ely 40" below the
surface- The �uvface,cicvation is approxi3natelp 217,5, The elevatiot3 of Ngh
water is approxirciatcIy 234. , The ei lfimalt!d high ground watcr labeled oil the
plans is 233.67. Docuknentation suppoi-ting the 233.67 water clevation should be
submitted. if the ground water is higher than that labcIcd, the water duality
volume within the cle€ention pond may be affected.
The inm-t into tho detention basin appears to be Iow and is actually beIO v the
invert elevation out of the detenLion ba.mT1. This will cause a hack water affecI.on
the dmivage pipe-
Calculations foi- the proposed 15" oudet pipe and 18" drain pipe on Willow Street
should be sip bmiIted, It is unclear•i l-tlio pipes have, adequate, capaci(y for the 100 -
year,,;Wi -n event- The. calculations should include, flows upgmikmt of tile,
propc3se.d manhole. Tailwatcr inipac#s should ako be included i11 the caleulati011S.
A new inanhele is proposed For the Willow Street dvainage system. The pipe
inverts should be modiFied such that pipe cmwiis snatch.
The sl4ge{stt>rageldic�chai-ge table shoixld be modified. The vol tjme cif storage
below the estimatcd water elevation should be �,,ero the impact of adjacent flood
levels should he cansiderod for the sl orms modeled.
Additional Co><nmejits
The ,�edjinent conwoI fbncc detail should iu<ci de hayhales as de,,;ci-shed jn ti c
Stormwatev Manageirient eport-
P is unL:le'cr whe-e the undcrdrain !s lccatiM. There is a cietf iI of the undez-di-ai>n
but it is not Shown Oil tile, plans.
The proposed WiIding is adjacent to the detention basin. Thal ! foundaIioB w 01
appears to he a reAai>nin g w a I for the basin. A portion of the wall appeai:s to be,
subrrrcvcd iascd on the aproxi mate fter e}eva#ic}n- This reign shot}id is
z vicwcd by tile, building ins pec(or,
S
We appvteciatu ttic 0VP051unity to assl"t dIC A Iilntrig Board can tilis pi-ojet~t and hope that
this i11fonnadon is sip fI'lcient for Youi, nccds. We wou[d he p]cased to mect with the
Board or the design enginc r to discuss thE,, project at your convenien-:c. if you have any
questions please tics not hesitute to contact rjs.
eTry IT-Lily yours,
OLBR & C OLAI TONTO, INC.
-/ hn C. Chessia, P.E.
cc. Mark 8- Gross, P,F:-
Jim Rand
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