addendum no. 5 (post bid) -...
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ADDENDUM NO. 5(POST BID)
RE: Phase 2 Improvements DATE: May 16, 2017New Administration BuildingWernle Youth & Family Treatment Center2000 Wernle RoadRichmond, Indiana
TO: All Bidders
Gentlemen:
This Addendum shall hereby be and become a part of the Contract Documents the same as iforiginally bound thereto.
The following clarifications, amendments, additions, revisions, changes, and modifications changethe original Contract Documents only in the amount and to the extent hereinafter specified in thisAddendum.
ITEM NO. 1: SUPPLEMENTAL INFORMATION
A. Included for reference is the Stormwater Drainage Report, dated 9/22/16.
ITEM NO. 2: CLARIFICATION
A. Owner to provide data cabling and terminations. Contractor to provide conduit and backboxes as indicated in the drawings.
ITEM NO. 3: PROJECT MANUAL; SECTION 08710 DOOR HARDWARE
A. Delete paragraph B.6.d. and substitute the following:
“d. Provide Schlage Primus #P04443, 6-pin, full size interchangeable cores, keyed tothe existing system.”
B. At all Hardware Groups where it occurs, delete FSIC Conventional Cylinder #26-091 andsubstitute with #20-763.
C. At all Hardware Groups where it occurs, delete FSIC Conventional Cylinder #20-057 andsubstitute with #20-757.
D. At the following seventeen (17) doors, Owner shall furnish closers for Contractor to install:
101A 101B 114A 114B 114C
116 118 119 120 121
130 131 133 134 201A
201B 228
ADDENDUM NO. 5 (POST BID) -2- May 16, 2017
ITEM NO. 4: DRAWING SHEET C2.0
A. Delete drawing C2.0 and substitute attached drawing C2.0, dated 9/22/16.
ITEM NO. 5: DRAWING SHEET C5.0
A. Delete drawing C5.0 and substitute attached drawing C5.0, dated 9/22/16.
ITEM NO. 6: DRAWING SHEET CE1.0
A. Install underground conduit and wiring to the water meter vault. Install one (1) GFCI outletwith weatherproof cover and box within the water meter vault.
ITEM NO. 7: DRAWING SHEET E6.2
A. Delete the Data Cable Specifications in its entirety, without substitutions.
END OF ADDENDUM NO. 5 (POST BID)
Stormwater Drainage Report
for:
Wernle Administration Building
2000 Wernle Road
Richmond, Indiana
Prepared by:
Patrick S. Brown, ASLA, LEED-AP
Registered Landscape Architect
September 22, 2016
Storm Drainage Report for: September 22, 2016 Wernle Administration Building Page 2
Contents
Project Description
Design Requirements
Existing Conditions
Stormwater Analysis
Pre-Development Watershed
Post Development Watershed
2-Year Pre-Development Runoff
10-Year Pre-Development Runoff
10-Year Post Development Runoff
100-Year Post Development Runoff
Detention Basin Design
Outlet Pipe Design
Site Grading Plan Revisions
Site Details Revisions
Post Construction Stormwater Management Plan
Attachments
USGS Richmond Quadrangle Map
Topographical Survey
Pre-Development Watershed Limits
Post Development Watershed Limits
Rainfall Frequency Atlas of the Midwest
2-Year Pre-Development Runoff Calculations
10-Year Pre-Development Runoff Calculations
10-Year Post Development Runoff Calculations
100-Year Post Development Runoff Calculations
Detention Basin Design Calculations
Outlet Pipe Design Calculations
Chart for Flow for Circular Pipes Flowing Full
Storm Drainage Report for: September 22, 2016 Wernle Administration Building Page 3
Project Description
This report has been prepared in conjunction with a project for the Wernle Youth & Family
Treatment Center for a construction of a new 2-level administration building and associated site
improvements. The project site is located on the southeastern portion of the campus adjacent
to Wernle Road. See Attachments for USGS Quadrangle Map, topographical survey for project
site location.
The purpose of this report is to analyze the stormwater runoff generated by the proposed
improvements and its potential affect on the existing site and stormwater facilities. The
proposed project consists of a 6,600 square foot building, parking and walkways.
The Richmond Sanitary District regulations states the discharge rates from the proposed
improvements will be reduced to the peak discharge rates equal to or less than the
undeveloped peak discharge rates for a 10-year storm event.
The existing stormwater runoff currently sheet flows across open lawn, grass and lightly
wooded area with an average slope 6%. Stormwater runoff is directed to the roadway swale,
flowing east, along Wernle Road.
Design Requirements
In accordance with the Richmond Sanitary District the storage volume required for new
improvements shall control the post-development of a 100-year storm. Detention areas shall
have an outlet structure which will discharge no more flow than the pre-development 10-year
storm. The outlet structure will consist of a pre-developed 2-year storm outlet to retain the
lower flows of the 2 to 10 year storm in the staged detention area.
Existing Conditions
The proposed project site sits on the southeast portion of the overall campus. The entire
campus is a rolling terrain with multiple watersheds. The existing project site is gently sloping
west to east with an estimated relief of approximately ten (10) feet. Drainage is primarily along
the ground surface into low lying areas and drainage swales. The project site is not located
within the FEMA 100-year flood plain and no regulated wetlands are located in the vicinity of
the project site.
According to the Soil Survey of Wayne County, Indiana published by the United States
Department of Agriculture Soil Conservation Service, the majority of the soils covering this site
are classified as Miami Silt Loam (MnB2) and Strawn Clay Loam (SuC3). Soil borings
conducted on-site found soils to be soft to medium stiff cohesive soils. Refer to Subsurface
Investigation & Geotechnical Recommendations report prepare by Alt & Witzig Engineering,
Inc. dated October 29, 2015 for detailed soils information.
The immediate project site has a watershed are of 3.43 acres. Refer to Attachments for
delineation of watershed limits of project site area.
Storm Drainage Report for: September 22, 2016 Wernle Administration Building Page 4
Stormwater Analysis
The quantity of stormwater runoff generated from a watershed can be affected by land
development and site improvements. Construction activities can alter the surface vegetation
and grades along with new hard surface areas reducing groundwater infiltration. A reduction in
infiltration will result in greater overland stormwater runoff rates. This study will analyze and
evaluate the net effect the proposed site improvements will have on the existing site.
The Rational Method was used to calculate 2-year and 10-year predevelopment conditions and
the 10-year post development conditions. The Modified Rational Method was used to calculate
the 100-year post development condition to determine the peak discharge rate.
Pre-Development Watershed – Project Limits
Tc = 20 minutes
Slope: +6%
Hydraulic Length: 700 feet
Land coverage: lawn, grasses, light woods
Refer to Attachments for Existing Watershed Map.
Post Development Watershed – Project Limits
The proposed development divides the existing watershed into two separate drainage areas
which each area will be served by a detention area. Refer to Attachments for Post
Development Watershed Map.
Detention Basin Drainage Area
Area: 1.33 acres
Development: new building, walks, patio and open lawn
South Detention Basin Drainage Area
Area: 2.10 acres
Development: parking, drive, walks and open lawn
2-Year Pre-Development Runoff = 2.761 cfs
Calculation for the 2-year storm based on Project Watershed Limits with a 20 minute rainfall
duration. Refer to Attachments for calculation worksheet.
10-Year Pre-Development Runoff = 4.514 cfs
Calculation for the 10-year storm based on Project Watershed Limits with a 20 minute rainfall
duration. Refer to Attachments for calculation worksheet.
10-Year Post-Development Runoff = 8.211 cfs
Calculation for the 10-year storm based on Project Watershed Limits with a 15 minute rainfall
duration. Refer to Attachments for calculation worksheet.
Storm Drainage Report for: September 22, 2016 Wernle Administration Building Page 5
100-Year Post-Development Runoff = 5.998 cfs peak discharge
Calculation for the 100-year storm based on Project Watershed Limits. The Modified Rational
Method was used to develop the peak discharge rate with a 2-year Pre-Development allowable
release. Total required storage, for 100-year storm, = 10,886 cu. ft. Refer to Attachments for
calculation worksheet.
Detention Basin Design
Sub-watershed drainage areas for the proposed development were defined. The North
Detention Basin receives approximately 25% of impervious surface runoff and the South
Detention Basin receives approximately 75% of impervious surface runoff. Refer to
Attachments for post-development watershed map and calculation worksheet.
Peak Discharge Storage = 10,886 cu. ft. (minimum storage required)
Detention basins storage capacity = 11,024 cu. ft.
Detention basins freeboard capacity = 7,995 cu. ft.
Detention basin total capacity = 20,019 cu. ft.
North Detention Basin at 25% = 2,939 cu. ft. (minimum storage required)
North Detention Basin Capacity = 3,302 cu. ft.
Available Freeboard = 2,247 cu. ft.
Total Storage Capacity = 5,549 cu. ft.
South Detention Basin at 75% = 7,947 cu. ft. (minimum storage required)
South Detention Basin Capacity = 8,722 cu. ft.
Available Freeboard = 5,748 cu. ft.
Total Storage Capacity = 14,470 cu. ft.
Outlet Pipe Design
Outlet pipes are designed to reduce water levels in the detention basins at the 2-year pre-
development runoff rate. The North Detention Basin will drain into the South Detention Basin
and the outlet pipe from the South Detention Basin will drain into the existing swale along
Wernle Road. Calculations performed to determine the orifice size of the outlet pipe. Refer to
Attachments for calculation worksheet.
2-Year Pre-Development Runoff = 2.761 cu. ft.
Calculated orifice opening = 0.31 sq. ft.
Proposed outlet pipe = 0.36 sq. ft. (8” HDPE corrugated, smooth
interior)
(Note: an orifice plate may be placed inside the Control Structures to reduce opening to
0.31 sq. ft. if deemed necessary)
Storm Drainage Report for: September 22, 2016 Wernle Administration Building Page 6
Outlet pipe for overflow conditions was designed on the South Detention Basin to allow for
emergency release of storm runoff greater than the 100-year storm peak discharge storage.
Outlet pipe was designed to meet or be less than the 10-year post development storm runoff.
Refer to Attachments for worksheet.
10-Year Post Development Storm Runoff = 8.211 cfs
Based on “Chart for Flow for Circular Pipes Flowing Full" (Manning Equation n = 0.013)
Pipe Design for 8.0 csf = 18” diameter, 0.5% slope at 4.2 fps velocity
Site Grading Plan Revisions
Drawing C2.0 Site Grading Plan has been revised, dated 09/22/16 showing revised Detention
Basin design and storm piping. A 6” perforated drain pipe was added to the stone drainage
bed along the downslope side of the parking lot. This perforated pipe will aid in the
conveyance of storm water directly to the detention basin and reduce overland surface flow
and possible erosion problems. Refer to Attachments for revisions.
Site Details Revisions
Drawing C5.0 Site Grading Plan has been revised, dated 09/22/16 showing a revised detail for
the parking lot stone edging and new details for the storm drainage control structures and
inlets. Refer to Attachments for revisions.
Storm Drainage Report for: September 22, 2016 Wernle Administration Building Page 7
Post Construction Stormwater Management Plan
1. Description of potential pollutant sources from proposed land use that may reasonably be
expected to add a significant amount of pollutants to stormwater discharges.
Pollutant sources after construction are minimal. There will be no on-site fueling stations
or operations that are high risk. Potential pollutant sources may include fuels/oils for
snow removal, lawn and landscape maintenance equipment. Runoff from parking areas
may include pollutants from vehicles. All non-pavement areas will be lawn which sill
reduce surface runoff of stormwater and allow filtration into subsoils.
2. Location, dimensions, detailed specifications, and construction details of all post
construction stormwater quality measures.
Stormwater quality measures are shown on SWPPP Plans and Details, Drawings C3.0,
C3.1 and C3.2. Stone drainage beds and stone drainage trenches are shown on
Drawings C2.0 and C5.0.
3. Description of measures that will be installed to control pollutants in stormwater discharges
after completion of construction activities.
Post construction measures include stone drainage bed along parking lot to trap runoff
sediment and pollutants from pavement areas. The stone drainage trench in the bottom
of the detention areas will help trap sediments and pollutants that settle in the basins.
The storm inlets have a sump at the bottom of the structures to collect sediments and
trash.
4. Sequence of installation of measures.
Sequence for storm water and erosion control measures are shown on Drawing C3.1
SWPPP Details.
5. Measures to prevent or minimize adverse impacts to stream and riparian habitat.
Stone rip-rap stone will be placed at ends of outlet pipes to reduce adverse effects of
storm water discharge into the existing drainage swale along Wernle Road.
Storm Drainage Report for: September 22, 2016 Wernle Administration Building Page 8
6. Description of maintenance guidelines for measures including: Facilitates proper long-term
function; and availability to future parties whom will be responsible for operation and
maintenance of measures.
Post development and long term maintenance functions to be performed by Owner
include:
Periodic inspections of stone drainage beds, stone drainage trenches and stone
rip-rap outlet pads to restore disturbed stones and remove any build up of
sediment and trash. Function to be performed minimum twice per year and after
major rain event.
Periodic inspections of storm structures (inlets and control structure basins) to
remove any build up of sediment and trash. Function to be performed minimum
twice per year.
Repair and restore any lawn erosion on a as needed basis.
Sweep parking lot pavements on a regular basis to remove sediment and debris.
Function to be performed twice a year minimally - once in the fall before winter
weather and again in the spring after the winter weather. Other sweepings shall
be done as needed.
Post development and long term maintenance functions to be included in Owner's
Standard Operations Manual to establish both short and long term care.
Rainfall Frequency Atlas of the MidwestRichmond, IN ‐ Area 6
Time
(Hr) (Inches) (In/Hr) (Inches) (In/Hr) (Inches) (In/Hr)
0.083 0.330 3.976 0.470 5.663 0.730 8.795
0.167 0.580 3.473 0.820 4.910 1.270 7.605
0.250 0.750 3.000 1.050 4.200 1.630 6.520
0.500 1.020 2.040 1.440 2.880 2.240 4.480
1.00 1.300 1.300 1.830 1.830 2.840 2.840
2.00 1.600 0.800 2.260 1.130 3.510 1.755
3.00 1.770 0.590 2.490 0.830 3.870 1.290
6.00 2.070 0.345 2.920 0.487 4.540 0.757
12.00 2.400 0.200 3.380 0.282 5.260 0.292
18.00 2.590 0.144 3.660 0.203 5.690 0.316
24.00 2.760 0.115 3.890 0.162 6.050 0.252
2 Year 10 Year 100 Year
Wernle Administation Building
2‐Year Pre‐Development ConditionsWatershed Area "A" 3.43 acres
Runoff Coefficient "C"
Existing cover: Grass / Trees
Existing grade: +6%
SCS Hydrologic Soils "C" at 2‐6% slopes: 0.16 to 0.21
SCS Hydrologic Soils "D" at 2‐6% slopes: 0.20 to 0.25
Projected Runoff Coefficient = .035
(assumed based on strong slopes, clay soils)
Rainfall Intensity "I":
2 Year, 20 minute storm = 2.3 in/hr
Q = ACI
Q = (3.43) (0.35) (2.3)
Q = 3.027
2‐Year Pre‐Development Runoff = 2.761 CFS
Wernle Administation Building
10‐Year Pre‐Development ConditionsWatershed Area "A" 3.43 acres
Runoff Coefficient "C"
Existing cover: Grass / Trees
Existing grade: +6%
SCS Hydrologic Soils "C" at 2‐6% slopes: 0.16 to 0.21
SCS Hydrologic Soils "D" at 2‐6% slopes: 0.20 to 0.25
Projected Runoff Coefficient = .035
(assumed based on strong slopes, clay soils)
Rainfall Intensity "I":
10 Year, 20 minute storm = 3.76 in/hr
Q = ACI
Q = (3.43) (0.35) (3.76)
Q = 4.514
10‐Year Pre‐Development Runoff = 4.514 CFS
10‐Year Post Development ConditionsTotal Project Watershed Drainage Area = 3.43 acres
Total Non‐impervious areas = 2.655 acres
Total Impervious areas = 33,695 sq.ft. = 0.775 acres
Building 6,600 sq.ft.
Parking 21,500 sq.ft.
Walks 5,595 sq.ft.
Weighted C = (3.43) (0.35) + (0.775 )(0.98) = 0.57
3.43
Rainfall Intensity "I":
10 Year, 15 minute storm = 4.20 in/hr
Q = ACI
Q = (3.43) (0.57) (4.20)
Q = 8.211
10‐Year Post‐Development Runoff = 8.211. CFS
Wernle Administation Building
100‐Year Post Development ConditionsTotal Project Watershed Drainage Area = 3.43 acres
Total Non‐impervious areas = 2.655 acres
Total Impervious areas = 33,695 sq.ft. = 0.775 acres
Building 6,600 sq.ft.
Parking 21,500 sq.ft.
Walks 5,595 sq.ft.
Weighted C = (3.43) (0.35) + (0.775 )(0.98) = 0.57
3.43
Modified Rational Method
Storm Duration
"D"
Rainfall
Intensity
"I"
Inflow
Rate
"Q"
(Q=ACI)
Allowable
Release
2‐Year
Pre‐Dev
"QAR"
Storage
Rate
(Q ‐ QAR)
(hrs) (in/hr) (cf/sec) (cf/sec) (cf/sec) (cf/sec) (cf)
0.083 (5 min) 8.795 17.195 2.761 14.434 0.100 4,349
0.167 (10 min) 7.605 14.868 2.761 12.107 0.168 7,339
0.25 (15 min) 6.520 12.747 2.761 9.986 0.208 9,063
0.5 (30 min) 4.480 8.759 2.761 5.998 0.250 10,886 Peak
1 2.840 5.552 2.761 2.791 0.233 10,133
2 1.755 3.431 2.761 0.670 0.112 4,866
3 1.290 2.522 2.761 ‐0.239 ‐0.060 ‐2,602
6 0.757 1.479 2.761 ‐1.282 ‐0.641 ‐27,914
12 0.438 0.857 2.761 ‐1.904 ‐1.904 ‐82,939
18 0.316 0.618 2.761 ‐2.143 ‐3.214 ‐140,022
24 0.252 0.493 2.761 ‐2.268 ‐4.536 ‐197,601
North Retention Basin Area = 27% Impervious Areas
27% of Peak Discharge = 2,939 cf
South Retention Basin Area = 73% Impervious Areas
73% of Peak Discharge = 7,947 cf
Required Storage
(QAR*D/12)
Wernle Administation Building
Detention Basin Capacity
North Detention Basin Area VolumeContour Elevation 26 3,859 sq.ft. Elevation 26
2,831 cu.ft. = Top of StorageContour Elevation 25 1,803 sq.ft.
471 cu.ft.Contour Elevation 24.50 80 sq.ft.
Storage Capacity 3,302 cu.ft.
Detention Freeboard Area VolumeContour Elevation 26.5 5,128 sq.ft. 0.5 Freeboard
2,247 cu.ft.Contour Elevation 26 3,859 sq.ft.
Freeboard Capacity 2,247 cu.ft.
TOTAL CAPACITY 5,549 cu.ft.
South Detention Basin Area VolumeContour Elevation 23.5 5,002 sq.ft. Elevation 23.5
4,604 cu.ft. = Top of StorageContour Elevation 23 4,206 sq.ft.
3,433 cu.ft.Contour Elevation 22 2,660 sq.ft.
685 cu.ft.Contour Elevation 21.5 80 sq.ft.
Storage Capacity 8,722 cu.ft.
Detention Freeboard Area VolumeContour Elevation 24.5 6,494 sq.ft. 1' Freeboard
5,748 cu.ft.Contour Elevation 23.5 5,002 sq.ft.
Freeboard Capacity 5,748 cu.ft.
TOTAL CAPACITY 14,470 cu.ft.
Summary Provided RequiredNorth Detention Basin Storage 3,302 cu.ft. 2,939 cu.ft.South Detention Basin Storage 8,722 cu.ft. 7,947 cu.ft.
Total 12,024 cu.ft. 10,886 cu.ft.
North Detention Basin freeboard 2,247 cu.ft.South Detention Basin Freeboard 5,748 cu.ft.
Total 7,995 cu.ft.
TOTAL BASIN STORAGE CAPACITY 20,019 cu.ft.
Wernle Administation Building
Outlet Pipe Design Calculations
Orifice/Culvert Flow Equation Q=CA(2gH)1/2
To find Orifice/Opening Area A = Q
C(2gH)1/2
2‐Year Pre‐Development Runoff = 2.761 cfs
A = 2.761
(0.60) (2) (32.2) (3.43)1/2
A = 2.761 = 0.31 sf
8.917
Outlet Pipe Design: 8" HDPE Corrugated Pipe = 0.363 sf
Detention Basin Outflow Pipe Design
Outflow pipe flow based on 10‐Year Post Construction Rainfall
= 8.211 cfs
Per 'Chart for FLow foR Circular Pipes Flowing Full" (Manning Equation n = 0.13)
8.211 cfs at 0.5% slope = 18" Pipe with 4.2 fps velocity