157 S Industrial Park Dr-20170905iu
Civil 16439 Briar Street
Omaha, NE 68136-4154
LI
Solutions, uc 402-895-5633
Robert Bouvia Drainage Study r 1, Q lid
Lot 8 Eriksen Subdivision
Blair, NE op
PROJECT UNDERSTANDING
Robert Bouvia is planning to build a 40' x 64' building with a crushed rock driveway to Grant
Street. The lot size is 1.99 acres, of which 0.50 acres is usable for construction. The remainder
of the lot is covered in wetlands.
The City of Blair, NE requires that storm water runoff from the 100 year storm event on a
developed condition must not exceed the historic condition.
The drainage analysis for the existing site conditions was completed using the Win TR -55 Small
Watershed Hydrology program developed by the Natural Resources Conservation Service
(MRCS). Output data includes storm water runoff for the 5 -yr, 10 -yr, 25 -yr, 50 -yr and 100 -yr
storm events.
EXISTING SITE CONDITIONS
From the Natural Resources Conservation Service, it was determined that the soils in this area
are classified as Luton and Albatron Silty Clay. The Hydrologic Soil Group for this soil is C/D.
Drainage from the site is generally from the east to the west. Storm runoff from the usable acres
(0.50) will be used to design the required storage.
Total area = 0.78 acres
Area = 0.78 acres Brush Area = 0.72 acres
Paved Street = 0.06 acres
Q 100 = 4.63 cfs
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ATTACHMENT NO. 1 - PROPOSED SITE LAYOUT
SCALE: 1"=20' ROW UNE DF GRAM STREET
PLAN LEGEND
c P.C. CONCRETE APPROACH
(PER CITY OF BLAIR REQUIREMENTS)
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BRUSH/ RAfs = 0.72
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PROPOSED SITE DRAINAGE
TOTAL ACRES = 0.78
ENT/BUILDING = 0.11
W=0.62
GRAVEL = 0.05
Q100 = 4.87 cfs
DRAINAGE BOUNDARY
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Soil Map—Washington County, Nebraska
MAP LEGEND
MAP INFORMATION
Area of Interest (AOI)
Spoil Area
The soil surveys that comprise your AOI were mapped at
0
Area of Interest (AOI)
Stony Spot
1:12,000.
Soils
1Z
Very Stony spot
Warning: Soil Map may not be valid at this scale.
F7
Soil Map Unit Polygons
s+n
Wet Spot
Enlargement of maps beyond the scale of mapping can cause
!
Soil Map Unit Lines
misunderstanding of the detail of mapping and accuracy of soil
,�
Other
line placement. The maps do not show the small areas of
p
soil Map unit Points
Special Line Features
contrasting soils that could have been shown at a more detailed
Special
Point Features
.�
scale.
�
Blowout
Water Features
Streams and Canals
Please rely on the bar scale on each map sheet for map
Borrow Pit
measurements.
Transportation
Clay Spot
�-f t
Rails
Source of Map: Natural Resources Conservation Service
r
Closed Depression
Web Soil Survey URL:
N
Interstate Highways
Coordinate System: Web Mercator (EPSG:3857)
Gravel Pit
My
US Routes
Maps from the Web Soil Survey are based on the Web Mercator
•
Gravelly Spot
_
Major Roads
projection, which preserves direction and shape but distorts
distance and area. A projection that preserves area, such as the
®
Landfill
Local Roads
Albers equal-area conic projection, should be used if more
Lava Flow
accurate calculations of distance or area are required.
.
Background
Marsh or swamp
E�L
Aerial Photography
This product is generated from the USDA-NRCS certified data as
of the version date(s) listed below.
'
Mine or Quarry
Soil Survey Area: Washington County, Nebraska
co)
Miscellaneous Water
Survey Area Data: Version 15, Sep 14, 2016
0
Perennial Water
Soil map units are labeled (as space allows) for map scales
IV
Rock Outcrop
1:50,000 or larger.
.Jl.-
Saline Spot
Date(s) aerial images were photographed: Feb 1, 2014—Nov
25, 2016
Sandy Spot
The orthophoto or other base map on which the soil lines were
.g�
Severely Eroded spot
compiled and digitized probably differs from the background
imagery displayed on these maps. As a result, some minor
Sinkhole
shifting of map unit boundaries may be evident.
Slide or Slip
oa
Sodic Spot
USDA Natural Resources Web Soil Survey 9/5/2017
Conservation Service National Cooperative Soil Survey Page 2 of 3
Soil Map—Washington County, Nebraska
Map Unit Legend
Washington County, Nebraska (NE177)
Map Unit Symbol
Map Unit Name
Acres in AOI
Percent of AO1
7710
Albaton silty clay, occasionally
flooded
2.5
34.3%
7711
Albaton silty clay, frequently
flooded
4.6
64.1%
7791
Luton silty clay, rarely flooded
0.1
1.6%
Totals for Area of Interest
7.1
100.0%
USDA Natural Resources Web Soil Survey 9/5/2017
Conservation Service National Cooperative Soil Survey Page 3 of 3
Map Unit Description: Albaton silty clay, occasionally flooded ---Washington County, Nebraska
Washington County, Nebraska
7710—Albaton silty clay, occasionally flooded
Map Unit Setting
National map unit symbol. f8hr
Elevation: 800 to 1,500 feet
Mean annual precipitation: 28 to 30 inches
Mean annual air temperature: 50 to 54 degrees F
Frost -free period: 150 to 170 days
Farmland classification: Not prime farmland
Map Unit Composition
Albaton, occasionally flooded, and similar soils: 87 percent
Minor components: 13 percent
Estimates are based on observations, descriptions, and transects of
the mapunit.
Description of Albaton, Occasionally Flooded
Setting
Landform: Flood plains
Down-slope shape: Linear
Across -slope shape: Linear
Parent material: Clayey alluvium
Typical profile
Ap - 0 to 7 inches: silty clay
Cg9 - 7 to 47 inches: clay
Cg2 - 47 to 65 inches: silty clay loam
2Cg3 - 65 to 80 inches: very fine sandy loam
Properties and qualities
Slope: 0 to 2 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Poorly drained
Runoff class: High
Capacity of the most limiting layer to transmit water (Ksat):
Moderately low to moderately high (0.06 to 0.20 in/hr)
Depth to water table: About 0 to 18 inches
Frequency of flooding: Occasional
Frequency of ponding: None
Calcium carbonate, maximum in profile: 30 percent
Available water storage in profile: Moderate (about 7.0 inches)
Interpretive groups
Land capability classification (irrigated): 3w
Land capability classification (nonirrigated): 3w
Hydrologic Soil Group: C/D
Ecological site: Clayey Overflow - Veg. zone 4 (R107XY069NE)
Hydric soil rating: Yes
USDA Natural Resources Web Soil Survey 9/5/2017
AiiiiiO Conservation Service National Cooperative Soil Survey Page 1 of 2
Map Unit Description: Albaton silty clay, occasionally flooded ---Washington County, Nebraska
Minor Components
Onawa, occasionally flooded
Percent of map unit: 13 percent
Landform: Flood plains
Down-slope shape: Linear
Across -slope shape: Linear
Ecological site: Clayey Overflow - Veg
Hydric soil rating: No
Data Source Information
Soil Survey Area: Washington County, Nebraska
Survey Area Data: Version 15, Sep 14, 2016
zone 4 (R107XY069NE)
USDA Natural Resources Web Soil Survey 9/5/2017
Conservation Service National Cooperative Soil Survey Page 2 of 2
Map Unit Description: Albaton silty clay, frequently flooded ---Washington County, Nebraska
Washington County, Nebraska
7711—Albaton silty clay, frequently flooded
Map Unit Setting
National map unit symbol. f8hs
Elevation: 800 to 1,500 feet
Mean annual precipitation: 28 to 30 inches
Mean annual air temperature: 50 to 54 degrees F
Frost -free period., 150 to 170 days
Farmland classification: Not prime farmland
Map Unit Composition
Albaton, depressional, frequently flooded, and similar soils: 70
percent
Minor components: 30 percent
Estimates are based on observations, descriptions, and transects of
the mapunit.
Description of Albaton, Depressional, Frequently Flooded
Setting
Landform: Oxbows on flood plains
Down-slope shape: Concave, linear
Across -slope shape: Linear
Parent material: Clayey alluvium
Typical profile
Ap - 0 to 7 inches: silty clay
Cg - 7 to 60 inches: clay
Properties and qualities
Slope: 0 to 1 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Very poorly drained
Runoff class: Negligible
Capacity of the most limiting layer to transmit water (Ksat):
Moderately low to moderately high (0.06 to 0.20 in/hr)
Depth to water table: About 0 to 12 inches
Frequency of flooding: Frequent
Frequency of ponding: Frequent
Calcium carbonate, maximum in profile: 30 percent
Available water storage in profile: Moderate (about 6.1 inches)
Interpretive groups
Land capability classification (irrigated): None specified
Land capability classification (nonirrigated): 5w
Hydrologic Soil Group: C/D
Ecological site: Clayey Overflow - Veg. zone 4 (R107XY069NE)
Hydric soil rating: Yes
u_SDA Natural Resources Web Soil Survey 9/5/2017
Conservation Service National Cooperative Soil Survey Page 1 of 2
Map Unit Description: Albaton silty clay, frequently flooded ---Washington County, Nebraska
Minor Components
Haynie, occasionally flooded
Percent of map unit: 15 percent
Landform: Flood plains
Down-slope shape: Linear
Across -slope shape: Linear
Ecological site: Silty Lowland - Veg
Hydric soil rating: No
zone 4 (R107XY070NE)
Onawet, depressional, frequently flooded
Percent of map unit: 15 percent
Landform: Oxbow lakes on flood plains
Down-slope shape: Linear
Across -slope shape: Linear
Ecological site: Clayey Overflow - Veg. zone 4 (R107XY069NE)
Hydric soil rating: Yes
Data Source Information
Soil Survey Area: Washington County, Nebraska
Survey Area Data: Version 15, Sep 14, 2016
USDA Natural Resources Web Soil Survey 9/5/2017
a" Conservation Service National Cooperative Soil Survey Page 2 of 2
Map Unit Description: Luton silty clay, rarely flooded ---Washington County, Nebraska
Washington County, Nebraska
7791—Luton silty clay, rarely flooded
Map Unit Setting
National map unit symbol: f8ij
Elevation: 1,000 to 1,500 feet
Mean annual precipitation: 28 to 30 inches
Mean annual air temperature: 50 to 54 degrees F
Frost -free period: 150 to 170 days
Farmland classification: Not prime farmland
Map Unit Composition
Luton, rarely flooded, and similar soils: 75 percent
Minor components: 25 percent
Estimates are based on observations, descriptions, and transects of
the mapunit.
Description of Luton, Rarely Flooded
Setting
Landform: Backswamps on flood plains
Down-slope shape: Concave, linear
Across -slope shape: Concave, linear
Parent material: Clayey alluvium
Typical profile
A - 0 to 12 inches: silty clay
Bkg - 12 to 24 inches: silty clay
Bkssyg - 24 to 33 inches: silty clay
Bssyg - 33 to 43 inches: silty clay
Bkyg - 43 to 50 inches: silty clay
B'kg - 50 to 60 inches: silty clay
Properties and qualities
Slope: 0 to 2 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Poorly drained
Runoff class: High
Capacity of the most limiting layer to transmit water (Ksat):
Moderately low to moderately high (0.06 to 0.20 in/hr)
Depth to water table: About 0 to 18 inches
Frequency of flooding: Rare
Frequency of ponding: None
Calcium carbonate, maximum in profile: 15 percent
Gypsum, maximum in profile: 5 percent
Available waterstorage in profile: Moderate (about 6.6 inches)
Interpretive groups
Land capability classification (irrigated): 3w
Land capability classification (nonirrigated): 3w
Hydrologic Soil Group: C/D
USDA Natural Resources Web Soil Survey 9/5/2017
Aiiiiiiiiiiii Conservation Service National Cooperative Soil Survey Page 1 of 2
Map Unit Description: Luton silty clay, rarely flooded ---Washington County, Nebraska
Ecological site: Clayey Overflow - Veg. zone 4 (R107XY069NE)
Hydric soil rating: Yes
Minor Components
Tieville, rarely flooded
Percent of map unit: 15 percent
Landform: Backswamps on flood plains
Down-slope shape: Concave, linear
Across -slope shape: Concave, linear
Ecological site: Clayey Overflow - Veg, zone 4 (R107XY069NE)
Hydric soil rating: Yes
Forney, rarely flooded
Percent of map unit. 10 percent
Landform: Backswamps, flood plains
Down-slope shape: Concave, linear
Across -slope shape: Concave, linear
Ecological site: Clayey Overflow - Veg. zone 4 (R107XY069NE)
Hydric soil rating: Yes
Data Source Information
Soil Survey Area: Washington County, Nebraska
Survey Area Data: Version 15, Sep 14, 2016
USDA Natural Resources Web Soil Survey 9/5/2017
NO Conservation Service National Cooperative Soil Survey Page 2 of 2
Attachment No. 4
Drainage Analysis - Existing Site Conditions
(7 pages)
WinTR-55 Current Data Description
--- Identification Data
User: Dan Norman Date: 9/5/2017
Project: Robert Bouvia Bldg Units: English
SubTitle: Lot 8, Eriksen Subdivision - Existing Drainage
Areal Units: Acres
State: Nebraska
County: Washington
Filename: F:\Civil Solutions\Robert Bouvia - Blair Property\Existing Site Drainage.w55
Sub -Area Data
Name Description Reach Area(ac) RCN Tc
--------------------------------
A1 Outlet 0.78 76 0.1
Total area: .78 (ac)
--- Storm Data --
Rainfall Depth by Rainfall Return Period
2 -Yr 5 -Yr 10 -Yr 25 -Yr 50 -Yr 100 -Yr 1 -Yr
(in) (in) (in) (in) (in) (in) (in)
-------------------------------------------------------------------------------
3.0 3.87 4.6 5.25 5.95 6.55 2.42
Storm Data Source: Washington County, NE (NRCS)
Rainfall Distribution Type: Type II
Dimensionless Unit Hydrograph: <standard>
WinTR-55, Version 1.00.10 Page 1 9/5/2017 11:14:57 PM
Dan Norman Robert Bouvia Bldg
Lot 8, Eriksen Subdivision - Existing Drainage
Washington County, Nebraska
Storm Data
Rainfall Depth by Rainfall Return Period
2 -Yr 5 -Yr 10 -Yr 25 -Yr 50 -Yr 100 -Yr 1 -Yr
(in) (in) (in) (in) (in) (in) (in)
--------------------- -
3.0 3.87 4.6 5.25 5.95 6.55 2.42
Storm Data Source: Washington County, NE (NRCS)
Rainfall Distribution Type: Type II
Dimensionless Unit Hydrograph: <standard>
WinTR-55, Version 1.00.10 Page 1 9/5/2017 11:14:58 PM
Dan Norman
Robert Bouvia
Bldg
Lot 8,
Eriksen Subdivision
- Existing Drainage
Washington County,
Nebraska
Watershed Peak
Table
Sub -Area
Peak Flow by Rainfall Return Period
or Reach
10 -Yr
25 -Yr 50 -Yr
100 -Yr
Identifier
(cfs)
(cfs) (cfs)
(cfs)
--------------------------------------------------------------
SUBAREAS
Al
2.66
3.30 4.01
4.63
REACHES
OUTLET
2.66
3.30 4.01
4.63
WinTR-55, Version 1.00.10 Page 1 9/5/2017 11:14:58 PM
Dan Norman Robert Bouvia Bldg
Lot 8, Eriksen Subdivision - Existing Drainage
Washington County, Nebraska
Hydrograph Peak/Peak Time Table
Sub -Area Peak Flow and Peak Time (hr) by Rainfall Return Period
or Reach 10 -Yr 25 -Yr 50 -Yr 100 -Yr
Identifier (cfs) (cfs) (cfs) (cfs)
(hr) (hr) (hr) (hr)
----------------------------------------------------------------------
SUBAREAS
Al 2.66 3.30 4.01 4.63
11.93 11.94. 11.93 11.93
REACHES
OUTLET 2.66
3.30 4.01
4.63
WinTR-55, Version 1.00.10 Page 1 9/5/2017 11:14:58 PM
Dan Norman Robert Bouvia Bldg
Lot 8, Eriksen Subdivision - Existing Drainage
Washington County, Nebraska
Sub -Area Summary Table
Sub -Area Drainage Time of Curve Receiving Sub -Area
Identifier Area Concentration Number Reach Description
(ac) (hr)
----------------------------------------------------------------------------
Al .78 0.100 76 Outlet
Total Area: .78 (ac)
WinTR-55, Version 1.00.10 Page 1 9/5/2017 11:14:58 PM
Dan Norman Robert Bouvia Bldg
Lot 8, Eriksen Subdivision - Existing Drainage
Washington County, Nebraska
Sub -Area Time of Concentration Details
Sub -Area
Flow
Mannings's End Wetted
Travel
Identifier/
Length
Slope
n Area Perimeter
Velocity Time
(ft)
(ft/ft)
(sq ft) (ft)
(ft/sec) (hr)
--------------------------------------------------------------------------------
Al
SHEET
13
0.0200
0.011
0.004
SHALLOW
21
. 0.0950
0.050
0..001
SHALLOW
191
0.0209
0.050
0.023
Time of Concentration 0.1
WinTR-55, Version 1.00.10 Page 1 9/5/2017 11:14:58 PM
Dan Norman Robert Bouvia Bldg
Lot 8, Eriksen Subdivision - Existing Drainage
Washington County, Nebraska
Sub -Area Land Use and Curve Number Details
Sub -Area Hydrologic Sub -Area
Identifier Land Use Soil Area
Group (ac)
-------------------------------------------------------------------------
Al Paved parking lots, roofs, driveways C .06
Pasture, grassland or range (good) C .72
Total Area / Weighted Curve Number .78
Curve
Number
98
74
76
WinTR-55, Version 1.00.10 Page 1 9/5/2017 11:14:58 PM
Attachment No. 5
Drainage Analysis - Proposed Site Conditions
(7 pages)
WinTR-55 Current Data Description
Identification Data
User: Dan Norman Date: 9/11/2017
Project: Robert Bouvia Bldg Units: English
SubTitle: Lot 8, Eriksen Subdivision - Proposed Drainage
Areal Units: Acres
State: Nebraska
County: Washington
Filename: F:\Civil Solutions\Robert Bouvia - Blair Property\Existing Site Drainage.w55
--- Sub -Area Data ---
Name Description Reach Area(ac) RCN Tc
---------------------- -----
A1 Outlet 0.78 78 0.1
Total area: .78 (ac)
--- Storm Data --
Rainfall Depth by Rainfall Return Period
2 -Yr 5 -Yr 10 -Yr 25 -Yr 50 -Yr 100 -Yr 1 -Yr
(in) (in) (in) (in) (in) (in) (in)
----------------- -----
3.0 3.87 4.6 5.25 5.95 6.55 2.42
Storm Data Source: Washington County, NE (NRCS)
Rainfall Distribution Type: Type II
Dimensionless Unit Hydrograph: <standard>
WinTR-55, Version 1.00.10 Page 1 9/11/2017 11:37:51 AM
Dan Norman Robert Bouvia Bldg
Lot 8, Eriksen Subdivision - Proposed Drainage
Washington County, Nebraska
Storm Data
Rainfall Depth by Rainfall Return Period
2 -Yr 5 -Yr 10 -Yr 25 -Yr 50 -Yr 100 -Yr 1 -Yr
(in) (in) (in) (in) (in) (in) (in)
-------------------------------------------------------------------------------
3.0 3.87 4.6 5.25 5.95 6.55 2.42
Storm Data Source:
Rainfall Distribution Type:
Dimensionless Unit Hydrograph
Washington County, NE (NRCS)
Type II
<standard>
WinTR-55, Version 1.00.10 Page 1 9/11/2017 11:37:51 AM
Dan Norman Robert Bouvia Bldg
Lot 8, Eriksen Subdivision - Proposed Drainage
Washington County, Nebraska
Watershed Peak Table
Sub -Area
Peak Flow by
Rainfall
Return Period
or Reach
10 -Yr 25 -Yr
50 -Yr
100 -Yr
Identifier
(cfs) (cfs)
(cfs)
(cfs)
-------------------------------------------------------------------------
SUBAREAS
Al
2.86 3.52
4.24
4.87
REACHES
OUTLET 2.86 3.52 4.24 4.87
WinTR-55, Version 1.00.10 Page 1 9/11/2017 11:37:51 AM
Dan Norman
Robert Bouvia
Bldg
Lot
8, Eriksen Subdivision -
Proposed Drainage
Washington County,
Nebraska
Hydrograph Peak/Peak
Time Table
Sub -Area
Peak
Flow and Peak Time (hr)
by Rainfall Return Period
or Reach
10 -Yr
25 -Yr 50 -Yr
100 -Yr
Identifier
(cfs)
(cfs) (cfs)
(cfs)
------------------------------------------------------------------------------
(hr)
(hr) (hr) (hr)
SUBAREAS
Al
2.86
3.52 4.24
4.87
11.94
11.94 11.93 11.93
REACHES
OUTLET
2.86
3.52 4.24
4.87
WinTR-55, Version 1.00.10 Page 1 9/11/2017 11:37:51 AM
Dan Norman Robert Bouvia Bldg
Lot 8, Eriksen Subdivision - Proposed Drainage
Washington County, Nebraska
Sub -Area Summary Table
Sub -Area Drainage Time of Curve Receiving Sub -Area
Identifier Area Concentration Number Reach Description
(ac) (hr)
---------------------------------------------------------------------
Al .78 0.100 78 Outlet
Total Area: .78 (ac)
WinTR-55, Version 1.00.10 Page 1 9/11/2017 11:37:51 AM
Dan Norman Robert Bouvia Bldg
Lot 8, Eriksen Subdivision - Proposed Drainage
Washington County, Nebraska
Sub -Area Time of Concentration Details
Sub -Area
Flow
Mannings's
Identifier/
Length
Slope
n
(ft)
(ft/ft)
-----------------------------------------
Al
SHEET
13
0.0200
0.011
SHALLOW
21
0.0950
0.050
SHALLOW
191
0.0209
0.050
End Wetted Travel
Area Perimeter Velocity Time
(sq ft) (ft) (ft/sec) (hr)
0.004
0.001
0.023
Time of Concentration 0.1
WinTR-55, Version 1.00.10 Page 1 9/11/2017 11:37:51 AM
Dan Norman Robert Bouvia Bldg
Lot 8, Eriksen Subdivision - Proposed Drainage
Washington County, Nebraska
Sub -Area Land Use and Curve Number Details
Sub -Area Hydrologic
Identifier Land Use Soil
Group
--------------------------------------------------------------
Al Open space; grass cover > 75% (good) C
Paved parking lots, roofs, driveways C
Gravel (w/ right-of-way) C
Total Area / Weighted Curve Number
Sub -Area
Area
(ac)
.62
.12
.04
.78
Curve
Number
74
98
89
78
WinTR-55, Version 1.00.10 Page 1 9/11/2017 11:37:51 AM
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ATTACHMENT NO 6 - EXISTING SITE
DIRECT RUNOFF, 100 YR STORM
1 4 6.55 � � 10 11 12
Rainfall lP), inches
a
7
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cri
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0 4.046
0
C
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ATTACHMENT NO 7 - PROPOSED SITE
DIRECT RUNOFF, 100 YR STORM
6 6.55 7 11' 12
Roinfall (P), inches
➢=i s e r�-'! f,�,r , iie::�r�� �ieienkicaai 9�a �n m suing ror rainfall and II1' ATTACHMENT NO. 8
DETENTION BASIN SZE
.6.
qo = 3.86 cfs, qi;= 4.06 cfs
---- _ qo/qi = 3.86/4.06 = 0.95
VsNr = 0.124
Vr = 53.33Q(A)
Vr = 53.33(4.06-3.86)(0.0012) = 0.013 ac -ft.
— --- - -Vs = 0.124(0.013)=-0.0016 ac -ft. - - -- -
= 70 cubic feet
NOTES: Q = DIFFERENCE BETWEEN EXISTING
C AND PROPOSED.
_ LES ---
� �} � A--AREA-IN-SQUARE-MI'
'D CD STORAGE VOLUME REQUIRED = 70 C.F.
-- — --
I
2 --
EXTRAPOLATED
0.124
.1
1 .4 .5 6 .i
Peak inf1o,.v discharge � G
fr- " (_' 1'0 -11 -TR -55, :ter'ond F[L,.,f-unv 1W)