Nace Engineering.03.18.20010
0
169 Haviland Road, Queensbury, NY 12804
Phone -518-745-4400 Fax-518-792-851
March 18, 2001
Froject 148
Mr. Chris Round RECEIVED
Director of Community Development
Town of Queensbury 1 „,
745 Bay Road `
Queensbury, NY 12804 TOWN OF O.UEFNSBURY
PLANK IOG OFFI^E
Re: Baybrook Professional Park — Subdivision No. 9-2000
Gentlemen:
In response to C.T. Male's comment letter of March 8`h, the Town of Queensbury Department of
Wastewater's letter of March 13`h and the Water Department's letter of March 14`h. we have the
following responses:
C.T. Male letter
The point of providing a reasonable outlet for the individual stormwater management
systems on each lot is well taken. Of the lots mentioned, numbers 5 and 15 are large lots that
have ample space for detention basins located outside of the DEC wetland buffer. These
basins can outlet toward the wetland, thereby maintaining the existing drainage patterns. I
am currently preparing a site design for lot #5. This site will have a series of shallow basins
which will outlet through a constructed buffer adjacent to the DEC buffer area. I have also
added two catch basins on Road #1 adjacent to lots #8 & #10. These will provide an outlet
for stormwater systems on those two lots. All other lots have access to natural drainage
outlets or the proposed stormwater collection system.
2. Where practical the earth berm parallel to the road has been eliminated. However, in areas
where the road is above the existing grade, this is not possible. In these areas rock check
dams have been shown to manage the existing site runoff in areas where it may collect along
the edge of the road fill.
3. Catch basin overflow structures have been added to all of the detention basin outlets. The
elevations of the grates on these structures have been set below the elevation of the overflow
spillway, but above the predicted 50-year storm elevation in the basin.
4. The rip -rap spillway has been moved away from the outlet pipe as suggested.
5. Unfortunately, both rainfall amounts are wrong (a gremlin must have gotten into my
computer). The culverts are sized for a 25 year storm which should be 4.5 inches for this
area. I have rerun the HydroCAD analysis with 4.5 inches and am enclosing a revised copy
of this portion of the Stormwater Management Report.
6. Between the printing of the Stormwater Report and printing of the plans, I eliminated the
original CB #9 and renumbered the remaining CB's. Therefore Catch Basins 410 through 17
in the Report are labeled one number too high. I have revised the CB numbering in the
Report and am enclosing a revised Watershed Routing Diagram and Routing List with the
correct CB numbers.
7. The runoff curve number was obtained from SCS TR-55, based upon Raynham silt loam
soils (group C) and a cover type of "Brush — brush -weed -grass mixture" in good condition
(meaning over 75% ground cover).
8. We will be submitting driveway permit and utility permit applications to Warren County.
Based upon prior experience, I believe that we will be required to bore for the sewer
crossing.
9. The 90 degree bend at station 9+00 on Road #2 is intended to be a three way stop, "T"
intersection with the eastern leg being the main entry road into a proposed development on
lot #15.
10. Both subbase geotextile and underdrains have been added to the road section as suggested.
The underdrains will outlet directly into the catch basins.
11. The estimate of maximum vehicular trip generation of 157 trips per hour included in the
Long Form EAF was derived from ITE Traffic Generation rates applied to full build -out of
lots #1 through #15. Potential future development of lot #16 with multi -family residential
development would add approximately 110 trips per hour. If this lot were to develop, it
would include a primary entrance on Meadowbrook Road.
12. The need to internalize access to all of the proposed lots, the location of the stream corridor
and the presence of DEC wetlands and associated buffer along the southwestern side of the
property have dictated the locations of the entrance roads for the subdivision.
Town Wastewater Dept. letter
1. 1 am currently preparing the Map, Plan and Report for the formation of a sewer district
extension for the proposed lots #1 through #15. When complete, I will submit this to the
Town for review.
2. We are currently coordinating the engineering aspects of our sewer force main with the
engineer for the Baybridge sewer project.
3. The roads and infrastructure for this project, including the sewers and pump station, will be
turned over to the Town of Queensbury.
4. The sewers and lift station are designed for the 100% build -out of lots #1 through #15. Lot
#16, if developed in the future, will be connected by a gravity sewer to the Hiland Pump
Station. The design flow for the proposed lift station is 20,000 GPD.
•
5. As stated above, the eastern portion of this property will be served through the Hiland Pump
Station, and will thus be in a different district.
6. The sewer manholes have been relocated to the center of one driving lane.
7. The force main has been noted as PVC SDR26.
8. Lateral connections have been shown from the sewer to the property line for each lot .
9. I disagree with the need for the gravity sewer to be extended to Bay Road since all of the
adjacent parcels are developed with the exception of the Hughes parcel on the north side of
this property. If that parcel were to develop, it would logically be served by a sewer along
the Old Maid Brook corridor and would connect to our proposed manhole #2. If other
parcels further north along Bay Road were to be served, they would connect directly into the
proposed Baybridge pump station.
10. Details for the boring under Bay Road will be added to the drawings as soon as we have
coordinated with Warren County Dept. of Public Works.
11. Details for lateral sewer connections have been added to the drawings.
12. Details for the connection to the Baybridge pump station will be added as soon as details for
the station are available.
13. 1 will coordinate with Mike Shaw to obtain specific requirements for pump station controls
and equipment.
Town Water Dept. letter
1. I will coordinate with Rich Schermerhom and Ralph Van Dusen to make a test excavation to
determine the depth of the existing Bay Road water main as suggested.
2. A note has been added to the tapping detail requiring a thrust block behind the sleeve.
3. All of the water main details have been changed to require 5'6" of cover.
Enclosed are copies of Drawings #S-3, S-4, S-7 & S-8 which have been revised as noted above.
Please let me know if there are any further comments or questions.
Sincerely,
Thomas W. Nace, P.E.
cc w/encl.: James Edwards, P.E.
Ralph Van Dusen
Mike Shaw
• 0 FILE
RECEIVED
TOWN OF CUEFN6BURY
PLANV,y; F I ^ r
STORMWATER MANAGEMENT REPORT
FOR
BAYBROOK PROFESSIONAL PARK
SUBDIVISION
HydroCAD RESULTS
DEVELOPED CONDITIONS
REVISED 3115101
(Catch basin numbers revised to agree with plans)
Data for 46148 BAYBROOPROFESSIONAL PARK - DEVELOPED • Page 1
TYPE II 24-HOUR RAINFALL= 4.80 IN
Prepared by NACE ENGINEERING, P.C. 18 Mar 01
HydroCAD 5.11 000576 (c) 1986-1999 Applied Microcomputer Systems
WATERSHED ROUTING_____________________________________________________________
O � O
1
Oz �Oz Os-a[]aF,-]->A
0�
0� A 0� �0
OSUBCATCHMENT ❑ REACH APDND 1 I LINK
SUBCATCHMENT
1
= ROAD #1
BAY ROAD TO CB #1/2
->
REACH
1
SUBCATCHMENT
2
= ROAD #1
CB #1/2 TO HIGH POINT
->
REACH
2
SUBCATCHMENT
3
= ROAD #2
CB #9/10 TO END
->
REACH
3
SUBCATCHMENT
4
= CB #5/6
TO CB #9/10
->
REACH
5
SUBCATCHMENT
5
= ROAD #2
START TO CB #5/6
->
REACH
4
SUBCATCHMENT
6
= ROAD #1
HIGH POINT TO CB #11/12
->
REACH
6
SUBCATCHMENT
7
= ROAD #1
CB #11/12 TO CB #13/14
->
REACH
7
SUBCATCHMENT
8
= ROAD #1
CB #13/14 TO END
->
REACH
8
REACH 1
= CB#1 TO
CB#3
->
REACH
2
REACH 2
= CB#4 TO
POND #1
->
POND
1
REACH 3
= CB#9 TO
POND #4
->
POND
4
REACH 4
= CB#6 TO
CB#8
->
REACH
5
REACH 5
= CB#8 TO
POND #2
->
POND
2
REACH 6
= CB#12 TO CB#14
->
REACH
7
REACH 7
= CB#14 TO CB#16
->
REACH
8
Data for 46148 BAYBROPPROFESSIONAL PARK - DEVELOPED Page 2
TYPE II 24-HOUR RAINFALL= 4.80 IN
Prepared by NACE ENGINEERING, P.C. 18 Mar 01
HydrOCAD 5.11 000576 (c) 1986-1999 Applied Microcomputer Systems
REACH 8 = CB#16 TO POND #3 -> POND 3
POND 1 = POND #1 ->
POND 2 = POND #2 ->
POND 3 = POND #3 ->
POND 4 = POND #4 ->
11
STORiYMWATER MANAGEMENT REPORT
FOR
BAYBROOK PROFESSIONAL PARK
SUBDIVISION
HydroCAD RESULTS
STREAM CULVERT SIZING
REVISED 3115101
(Rainfall amount corrected to 4.5 inches)
Data for BAYBROOK SUBIR EXISTING WATERSHED Page 1
TYPE II 24-HOUR RAINFALL= 4.50 IN
Prepared by NACE ENGINEERING, P.C. 18 Mar 01
HydroCAD 5.11 000576 (c) 1986-1999 Applied Microcomputer Systems
WATERSHED ROUTING = -------------- _______________---- ___________________________
SUBCATCHMENT 1
SUBCATCHMENT 2
SUBCATCHMENT 3
REACH 1
REACH 2
REACH 3
POND 1
O
OSUBCATCHMENT REACH Q PCND 1 I LINK
= SUBCATCH 1
= SUBCATCH 2
= SUBCATCH 3
= UPPER STREAM
= MIDDLE STREAM
= LOWER STREAM
= NEW CULVERT WITH UPSTREAM STORAGE
-> REACH 1
-> REACH 2
-> REACH 3
-> REACH 2
-> REACH 3
-> POND 1
Data for BAYBROOK SUBD. EXISTING WATERSHED Page 2
TYPE II 24-HOUR RAINFALL= 4.50 IN
Prepared by NACE ENGINEERING, P.C. 18 Mar 01
HydroCAD 5.11 000576 (c) 1986-1999 Applied Microcomputer Systems
SUBCATCHMENT 1
SUBCATCH 1
PEAK= 6.01 CFS @ 12.85 HRS, VOLUME= 1.86 AF
ACRES CN SCS TR-20 METHOD
97.30 45 WOODS, BRUSH, SOME DEVELOPMENT TYPE II 24-HOUR
RAINFALL= 4.50 IN
SPAN= 10-20 HRS, dt=.1 HRS
Method
Comment
Tc (min)
TR-55 SHEET FLOW
Segment ID:
45.3
Woods: Light underbrush n=.4
L=300' P2=2.4
in s=.04
SHALLOW CONCENTRATED/UPLAND FLOW
Segment ID:
9.6
Woodland Kv=5 L=500' s=.03
'/' V=.87 fps
Total Length=
800 ft
Total Tc=
54.9
SUBCATCHMENT 2 SUBCATCH 2
PEAK= 38.56 CFS @ 12.63 HRS, VOLUME= 6.79 AF
ACRES CN
SCS TR-20
METHOD
105.00 52 WOODS, BRUSH
TYPE II
24-HOUR
25.00 70 DEVELOPED AREA
RAINFALL=
4.50 IN
130.00 55
SPAN=
10-20 HRS,
dt=.1 HRS
TR-55 SHEET FLOW Segment ID: 45.3
Woods: Light underbrush n=.4 L=300' P2=2.4 in s=.04
SHALLOW CONCENTRATED/UPLAND FLOW Segment ID: 9.6
Woodland Kv=5 L=500' s=.03 '/' V=.87 fps
3
SUBCATCH 3
Total Length= 800 ft Total Tc= 54.9
PEAK= 66.65 CFS @ 12.42 HRS, VOLUME= 8.01 AF
ACRES CN SCS TR-20 METHOD
43.10 80 DEVELOPED AREAS INC. ROADS TYPE II 24-HOUR
RAINFALL= 4.50 IN
SPAN= 10-20 HRS, dt=.1 HRS
Method Comment Tc (min)
TR-55 SHEET FLOW Segment ID: 39.7
Grass: Dense n=.24 L=300' P2=2.4 in s=.02
SHALLOW CONCENTRATED/UPLAND FLOW Segment ID: 7.9
Kv=6 L=400' s=.02 '/' V=.85 fps
Total Length= 700 ft Total Tc= 47.6
Data for BAYBROOK SUBD•.- EXISTING WATERSHED • Page 3
TYPE II 24-HOUR RAINFALL= 4.50 IN
Prepared by NACE ENGINEERING, P.C. 18 Mar 01
HydrOCAD 5.11 000576 (c) 1986-1999 Applied Microcomputer Systems
REACH 1
UPPER STREAM
Qin = 6.01 CFS @ 12.85 HRS, VOLUME= 1.86 AF
Qout= 5.16 CFS @ 13.31 HRS, VOLUME= 1.77 AF, ATTEN= 140, LAG= 27.7 MIN
DEPTH END AREA DISCH
(FT)
(SO -FT)
(CFS)
0.00
0.00
0.00
.30
1.98
1.82
.60
4.32
5.98
.90
7.02
12.20
1.29
11.07
23.42
1.80 17.28 43.72
2.40 25.92 76.48
3.00 36.00 119.75
REACH 2
6' x 3' CHANNEL
SIDE SLOPE= .5
n= .05
LENGTH= 2000 FT
SLOPE= .0055 FT/FT
MIDDLE STREAM
STOR-IND METHOD
PEAK DEPTH= .54 FT
PEAK VELOCITY= 1.3 FPS
TRAVEL TIME = 24.9 MIN
SPAN= 10-20 HRS, dt=.1 HRS
Qin = 40.73 CFS @ 12.68 HRS, VOLUME= 8.57 AF
Qout= 36.05 CFS @ 12.92 HRS, VOLUME= 8.33 AF, ATTEN= 11%, LAG= 14.4 MIN
DEPTH END AREA DISCH
(FT)
(SO -FT)
(CFS)
0.00
0.00
0.00
.30
1.98
2.33
.60
4.32
7.65
.90
7.02
15.61
1.29
11.07
29.96
1.80
17.28
55.93
2.40 25.92 97.84
3.00 36.00 153.19
REACH 3
6' x 3' CHANNEL
SIDE SLOPE= .5
n= .05
LENGTH= 3000 FT
SLOPE= .009 FT/FT
LOWER STREAM
STOR-IND METHOD
PEAK DEPTH= 1.41 FT
PEAK VELOCITY= 2.9 FPS
TRAVEL TIME = 17.4 MIN
SPAN= 10-20 HRS, dt=.1 HRS
Qin = 84.98 CFS @ 12.56 HRS, VOLUME= 16.33 AF
Qout= 82.97 CFS @ 12.66 HRS, VOLUME= 16.17 AF, ATTEN= 2e, LAG= 6.2 MIN
DEPTH END AREA DISCH
(FT) (SO -FT) (CFS)
0.00 0.00 0.00
.30 1.98 2.33
.60 4.32 7.65
.90 7.02 15.61
1.29 11.07 29.96
1.80 17.28 55.93
2.40 25.92 97.84
3.00 36.00 153.19
6' x 3' CHANNEL
SIDE SLOPE= .5
n= .05
LENGTH= 1600 FT
SLOPE- .009 FT/FT
STOR-IND METHOD
PEAK DEPTH= 2.18 FT
PEAK VELOCITY= 3.6 FPS
TRAVEL TIME = 7.4 MIN
SPAN= 10-20 HRS, dt=.1 HRS
Data for BAYBROOK SUBD. EXISTING WATERSHED Page 4
TYPE II 24-HOUR RAINFALL= 4.50 IN
Prepared by NACE ENGINEERING, P.C. 18 Mar 01
HydroCAD 5.11 000576 (c) 1986-1999 Applied Microcomputer Systems
POND 1 NEW CULVERT WITH UPSTREAM STORAGE
Qin = 82.97 CFS @ 12.66 HRS, VOLUME= 16.17 AF
QOut= 82.99 CFS @ 12.68 HRS, VOLUME= 16.13 AF, ATTEN= 0%, LAG= 1.3 MIN
ELEVATION AREA INC.STOR CUM.STOR STOR-IND METHOD
(FT) (SF) (CF) (CF) PEAK STORAGE = 4265 CF
0.0 100 0 0 PEAK ELEVATION= 3.2 FT
1.0 500 300 300 FLOOD ELEVATION= 4.0 FT
2.0 1500 1000 1300 START ELEVATION= 0.0 FT
3.0 3000 2250 3550 SPAN= 10-20 HRS, dt=.1 HRS
4.0 6000 4500 8050 Tdet= 1.6 MIN (15.97 AF)
# ROUTE INVERT OUTLET DEVICES
1 P 0.0' 42" CULVERT X 2
n=.01 L=80' S=.005'/' Ke=.5 Cc=.9 Cd=.6 TW=2.2'