HomeMy WebLinkAboutDrainage Reports - 04/03/1992Final nnroved Report
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THIS PRELIMINARY AND FINAL DRAINAGE STUDY AND REPORT FOR SUNSTONE
VILLAGE 6TH SUBDIVISION (FILING 6) WAS PREPARED BY LAND
DEVELOPMENT SERVICES USING THE CITY OF FORT COLLINS STORM
DRAINAGE DESIGN CRITERIA, dated May, 1984.
The results of this drainage study are reported in the enclosed
text and supporting documents, and are shown in further detail on
the Utility Plans submitted concurrently with this report. This
report is a revision of the original report dated July 1, 1991.
Signed this 121h_d,2Y_Q£_March, 1992.
Dennis L. Donovan, P.E.
Land Development Services
309 W. Harmony Road — Unit A
Fort Collins, Colorado 80526
Phone (303) 225-9244
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SUNSTONE VILLAGE 6TH SUBDIVISION P.U.D.
PRELIMINARY AND FINAL STORM DRAINAGE REPORT
I. GENERAL INFORMATION
Sunstone Village 6th Subdivision P.U.D. (6th filing) is a
proposed single family subdivision in the City of Fort Collins,
Colorado. The site is generally located east of Timberline Road
and north of Harmony Road in southeast Fort Collins.
The Sunstone Village 6th filing is a part of the Timberline
Farm P.U.D., which consists of the West 1/2 of the Southwest 1/4
of Section 32, T7N, R68W, Sixth Principal Meridian, Larimer
County, Colorado. The proposed development consists of 34 lots
on 9.76 acres, which is consistent with the approved Master Plan.
The 6th filing is bounded on the north by Sunstone Village
5th Subdivision P.U.D. (5th filing), on the east by Harmony
Village Mobile Home Court, and on the south and west by
undeveloped land that is also a part of Timberline Farm P.U.D.
The 6th filing is a part of the property identified as
Timberline Farm — Phase B on the Master Drainage and Utility Plan
prepared for the City by Engineering Professionals, Inc. (EPI) of
Fort Collins. EPI also prepared the Master Drainage Report for
Timberline Farm P.U.D. and both the Preliminary and Final
Drainage Reports for Sunstone Village 5th Subdivision P.U.D.
All of the 6th filing is a part of Drainage Basin 2, as
identified in the Master Drainage Report.
The Sunstone Village development includes four filings that
are located outside of the Timberline Farm P.U.D. boundaries.
The 5th filing ,was the fist development within Timberline Farm
P.U.D. All of the Sunstone Village and Timberline Farm property
is located within reach 2 of the City designated Fox Meadows
Drainage Basin.
The 6th filing has historically been used for agricultural
purposes. It is part of a larger basin that drains to the
north. The site has slopes of 1/2% to 1 and 1/2%. Off —site
drainage onto the site consists of sheet flow from the
undeveloped area to the west. There are no active irrigation
ditches within the site.
A drainage swale and detention system exists downstream from
the 6th filing within the 5th filing. The existing swale in the
northeast corner of the 6th (and southeast corner of the 5th)
filing provides a storm water discharge point for the easterly
portion of the site.
Most of the westerly portion of the site will drain
northerly and then westerly into the streets, storm sewer system
and, ultimately, the detention facilities in the 5th filing. The
remainder of the site consists of back yard areas that will flow
easterly onto developed lots and along lot lines to the drainage
improvements in the 5th filing. All of the storm drainage
systems are in general accordance with the Master Drainage Plan.
SUNSTONE VILLAGE 6TH SUBDIVISION P.U.D.
PRELIMINARY AND FINAL STORM DRAINAGE REPORT
The storm water detention system downstream in the 5th
filing was designed to accommodate direct (undetained) storm
runoff from the 6th filing. Accordingly, no detention facilities
are provided within the 6th filing. Additionally, no basin —wide
improvements for the Fox Meadows Drainage Basin are required for
the 6th filing.
A preliminary street and grading plan was prepared for the
off —site area to the south of the 6th filing in order to estimate
the impact of storm runoff after future development to the storm
drainage system in the 6th filing. This area of Timberline Farm
P.U.D. — Phase B will probably be developed in 1992 as the 7th
filing.
II. Proposed Storm Drainage Plan
The proposed drainage plan for the 6th filing is in general
compliance with the Master Drainage Report. The site has been
divided into eight (8) sub basins for design purposes. In
addition, three off —site sub —basins were identified as being
contributory to the storm runoff design considerations within the
6th filing.
The 8 sub basins within the 6th filing are identified at
Exhibit A, which is the Grading and Drainage Plan (Sheet 7 of 8)
of the Construction Drawings for the 6th filing. Exhibit B
(identified as the Overall Drainage [lap) is also included at the
end of this report showing the three off site sub basins, as well
as the 8 on —site sub basins.
Sub basins #1,#2 and the westerly one—third of #3 will drain
to the intersection of Stoney Creek Drive and the cul—de—sac
serving Lots 16 through 27. There, the runoff will be joined by
future flows from off —site sub basin #0-1 and on site sub basin
#4, which will drain from the south in Stoney Creek Drive to the
intersection. The flows from sub basins #0-1 and #4 entering the
6th filing in Stoney Creek Drive from the south (after future
development) are identified at Exhibit A as Design Point A.
The storm runoff
intersection from the
runoff from the north
filing to comprise all
Storm runoff from the
tract on the east side
Point B on Exhibit A.
reaching the Stoney Creek Drive/cul—de—sac
west and south will be joined by storm
from off —site sub basin C-6 in the 5th
of the storm runoff at this intersection.
intersection to the east into the drainage
of the 6th filing is identified as Design
According to the Master Drainage Report,
Timberline Farm P.U.D. area south and west of
drain to and along the Drainage Tract on the
more -of the
the 6th filing will
east side of the 6th
SUNSTONE VILLAGE 6TH SUBDIVISION P.U.D..
PRELIMINARY AND FINAL STORM DRAINAGE REPORT
filing. However, a storm water detention facility to be
constructed within the off —site area will limit the discharge
during a 100 year design storm to 8 cubic feet per second (cfs).
The Master Drainage Report identifies a pipe culvert and
overflow swale to carry storm runoff in the Tract on the east
side of the 6th-filing between the proposed detention facility to
the south and the existing detention facility in the 5th filing.
The swale connecting the existing and proposed detention
facilities is identified on Exhibit A as Section B—B.
However, the 5th filing Final Drainage Plan and Report did
not include the pipe culvert. Considering the low design
discharges to be contained within the drainage tract on the east
side of the 6th filing, only a drainage Swale is proposed in this
location.
Since the slope of the drainage swales are less than two (2)
percent, a two foot wide concrete low flow pan has been designed
and included to protect both swales (Section A —A and B—B) invert
from damage from nuisance flows.
On —site sub basins #5,#69 and #8 will drain to the
intersection of Stoney Creek Drive and Summerstone Court.
Additionally, off —site sub basin # 0-2 will contribute storm
runoff to this location, which is identified at Exhibit A as
Design Point C.
The Hydrologic Characteristics for the on —site and off —site
sub —basins, as well as for the combined sub basins at the three
Design Points are included oh,the following page as Table I.
PAGES
HYDROLOGIC
CHARACTERISTICS
SUNSTONE VILLAGE 6TH FILING
2 YEAR 100 YEAR
BASIN
AREA C
VALUE TIME OF TIME OF 12-YR
i
100-Y
Q 2-YR Q
100-YR DESIGN
DESIGNATION
CONCEN- CONCEN-
IGN
NT
TRATION TRATION
(ACRES)
(MIN) (MIN) (in/hr)
(in/hr
(CFS)
(CFS)
ON -SITE
#1
1.79
0.4 14.2 11.4
2.2
6.7
1.6
6.0
#2
2.19
0.5 18.3 14.7
1.9
6.0
2.1
8.2
03
1.35
0.5 13.9 12.3
2.2
6.5
1.5
5.5
#4
0.15
0.25 10.0 10.0
2.5
7.2
0.1
0.3
#5
1.23
0.6 11.0 10.0
2.4
7.2
1.8
6.6
#6
1.26
0.6 10.8 10.0
2.4
7.2
1.8
6.8
#7
1.40
0.25 10.0 10.0
2.5
7.2
0.9
3.2
#8
0.40
0.8 10.4 10.0
2.5
7.2
0.8
2.9
OFF -SITE
#0-1
#0-2
#C-6
COMBINED
FLOWS
#0-1 & #4
#2,#3,W1/3
OF #1,#4,
#0-1 & #C-6
#5,#6,#8,
& # 0-2
2.62 0.6 13.1 10.0 2.2 7.2 3.5
0.30 0.5 10.0 10.0 2.5 7.2 0.4
0.80 0.5 15.1 12.0 2.1 6.6 0.8
2.77
0.6
13.1
11.4
7.61
0.54
18.3
14.7
3.19
0.63
16.9
13.1
2.2
6.7
3.7
1.9
6.0
7.8
2.0
6.5
4.0
12.6
1.4
2.9
13.9 A
30.8 B
16.3 C
Pa6F �
SUNSTONE VILLAGE 6TH SUBDIVISION P.U.D.
PRELIMINARY AND FINAL STORM DRAINAGE REPORT
The Time of Concentrations were determined using the
equation for overland flow in the design manual, and then by
adding the time of gutter flow - which was estimated to be at a
velocity of 1.5 feet per second for the 2 year storm and 2 feet
per second for the 100 year storm - to the point of discharge
from the particular sub basin.
The formula for Time of Concentration is:
Tc = [1.87 (1.1 - CCf) D1/21 / S1/3
The following
is a
summary
of the
2 year,
or Minor
Storm,
Hydrologic
calculations
for the
eight sub
basins (i.e.
Cf = 1.0):
Overland
Flow
Gutter
Flow
Total Time
Sub basin
L
Delta
H S
Tc
L
Tc
Tc
ft
ft
%
min
ft
min
min
1
60
1.6
2.7
7.3
620
6.9
14.2
2
230
4.2
1.8
14.0
390
4.3
18.3
3
160
3.6
2.2
9.7
380
4.2
13.9
4
minimum
10.0
5
115
2.1
1.8
8.2
250
2.8
11.0
6
120
2.6
-2.2
7.9
260
2.9
10.8
7
minimum
10.0
8
270
1.9
0.7
10.4
N/A
10.4
The following is a summary of the 100 year, or Major Storm,
Hydrologic calculations for the eight sub basins (i.e. Cf =
1.25):
Overland
Flow
Sub basin
L
Delta
H S
ft
ft
%
1
60
1.6
2.7
2
230
4.2
1.8
3
160
3.6
2.2
4
minimum
5
minimum
6
minimum
7
minimum
8
minimum
Gutter Flow
Tc
L
Tc
min
ft
min
6.2
620
5.2
11.1
390
3.6
8.6
380
3.7
Total Time
Tc
min
11.4
14.7
12.3
10.0
10.0
10.0
10.0
10.0
The Time of Concentration for combined sub basins was
determined using the longest time of concentration for any of the
sub basins contributing at that point.
III. DESCRIPTION OF STREET FLOWS AND DRAINAGE IMPROVEMENTS
Due to the relatively small areas of the on -site sub basins
and the off -site sub basins that will contribute storm runoff to
the 6th filing, the concentration of discharges in the street
gutters will be somewhat minor. /' '# 61= E
SUNSTONE VILLAGE 6TH SUBDIVISION P.U.D.
PRELIMINARY AND FINAL STORM DRAINAGE REPORT
The largest flow in a gutter will be from the combined sub
basin #,s 5.6 and 8. There a 2 year "minor" design discharge of
4.0 cfs is estimated, and a 100 year "major" design discharge of
16.3 cfs is estimated. The slope of the street at that location
is 0.8 percent.
According to Figure 4-1 of the design manual and using the
following criteria: Cross Slope of 2 %, so a Reciprocal (Z) of
50; a Roughness Coefficient (n) of 0.016 from Table 4-3; and an
allowable depth of flow in the gutter of 6 inches during a two
year storm, the gutter will carry about 25 cfs before exceeding
City criteria. That capacity is about one and one—half times
the 100 year storm discharge at Design Point C. Obviously, street
flow encroachment is not a problem.
For the streets at 0.5 percent gutter slope, the capacity is
about 20 cfs at 6 inches deep. The largest gutter flow in a
street at this minimum slope is only about 2 cfs. Obviously,
street gutter flows in the 6th filing are well within City of
Fort Collins criteria.
Storm drainage facilities, or improvements, for the 6th
filing include cross pans at the intersections, a 12 foot cross
pan across Stoney Creek Drive, a 12 foot sidewalk culvert from
Stoney Creek Drive to the drainage tract between Lots 30 and 31,
and open channel/swale improvements in the drainage tracts.
Because of a lack of positive drainage in the abutting lots
in the existing 5th filing, drainage swales with concrete pans on
the rear of 6th filing Lots 5, 10, 11, 15, 17 & 18 will be
required to intercept flows from the 6th filing. A portion of
the flows will drain to the existing drainage swale/easement
between Lots 67 & 68 of the 5th filing. The remainder will flow
to a new 10 foot sidewalk culvert into Stoney Creek Drive at the
northeast corner of Lot 15 in the 6th filing. Cross Section C—C
is provided at Exhibit A that provides hydraulic characteristices
of the swales along the rear lot lines.
Cross Sections A —A and B—B are shown at Exhibit A that
provide the hydraulic characteristics of the open channels that
are to be constructed in the drainage tract. For the reach from
Stoney Creek Drive downstream between Lots 30 and 31, the Swale
will carry 37.9 cfs at a depth of 1.8 feet. The 100 year storm
discharge is estimated to be 30.8 cfs, so the channel section is
adequate to pass the major storm discharge.
The larger channel running south to north in the drainage
tract on the east side of the 6th filing will carry 52.7 cfs at
the minimum depth of 2.0 feet. The major storm near the north
end of the channel (where it will tie into the existing channel
in the fifth filing) is estimated to be only 39.6 cfs. The
channel section will easil.y handle the 100 year storm.
FA G E
SUNSTONE VILLAGE 6TH SUBDIVISION P.U.D.
PRELIMINARY AND FINAL STORM DRAINAGE REPORT
During the interim time prior to development of the 7th
filing and the proposed detention pond in the southeast corner of
Sunstone Village, the Swale along the east side (Section B—B)
will be adequate to pass the 100 year historic flows from the
area to the west. Maybe two acres of crop land will drain into
the swale. That equates to only 3 or 4 cfs. Most of the area
that will be routed through the proposed detention facility flows
southeasterly to a natural swale that does not pass trough the
6th filing.
When completed, landscaped, and subject to a warranty period
for the improvements, the City of Fort Collins has agreed to
accept ownership of the drainage tract for future maintenance of
the integrity of the drainage capacity.
In summary, the proposed storm drainage for the Sunstone
Village 6th filing is rather minor in scope, and the resulting
storm drainage system should adequately protect life and property
on the site.
40-rF : Ne�(T
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INTERMILL LAND SURVEYING, INC.
1301 North Cleveland Avenue
LOVELAND, COLORADO 80537
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INTERMILL LAND SURVEYING, INC.
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LOVELAND, COLORADO 80537
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THIS PRELIMINARY AND FINAL EROSION CONTROL PLAN REPORT FOR
SUNSTONE VILLAGE 6TH SUBDIVISION (FILING 6) WAS PREPARED BY LAND
DEVELOPMENT SERVICES USING THE CITY OF FORT COLLINS EROSION
CONTROL REFERENCE MANUAL for Construction Sites, dated January,
1991.
The results of this erosion control study are reported in the
enclosed text and supporting documents, and are shown in further
detail on the Utility Plans.submitted concurrently with this
report. This report is a revision to the original report dated
July 1, 1991.
Signed this 1$£h_daY_Q£_February, 1992.
Dennis L. Donovan, P.E.
Land Development Services
309 W. Harmony Road — Unit B
Fort Collins, Colorado 80526
Phone (303) 225-9244
SUNSTONE VILLAGE 6TH SUBDIVISION P.U.D.
PRELIMINARY AND FINAL EROSION CONTROL PLAN REPORT
The erosion control concepts and general design
consideration for the Sunstone Village 6th Subdivision P.U.D.
(6th filing) are outlined in the following paragraphs and shown
in further detail on Exhibit A. The exhibit is the same as for
the storm drainage report, and is Sheet 7 of 8 of the
Construction Drawings titled OVERALL GRADING, DRAINAGE & EROSION
CONTROL PLAN.
It was determined from the reference manual and a Wind
Erodibility Zone Map that the Erodibility Zone for both Rainfall
Erosion and Wind Erosion is moderate for the site. Standard Form
A "RAINFALL PERFORMANCE STANDARD EVALUATION" follows this text.
It identifies the two areas of concern for an erosion control
plan and identifies their pertinent basin characteristics..
Sub basins 1,2 and 3 will drain to the northeast corner of
the site and exit into the existing Swale and detention facility
in the 5th filing. That area requires a Performance Standard of
78.0 percent from Table 5-1 of the manual.
Sub basins 5,6 and 8 will flow to the 5th filing at the
intersection of Summerstone Court and Stoney Ridge Drive. Table
5-1 indicates a required Performance Standard of 76.0 percent.
Sub basins 4 and 7 are not needing to be disturbed with grading,
so they can be left in their current situation planted with
crops.
Standard Form B "EFFECTIVENESS CALCULATIONS" follows Form A
and identifies the recommended erosion control measures and their
effect on the site.
Sub basins 1,2 &3 contain
will be concrete and pavement.
will not have to be disturbed
Rainfall erodibility deterents
culvert at Stoney Creek Drive,
tract at the northeast corner,
swale as it daylights into the
5.33 acres, of which 0.81 acres
About one—third of the remainder
during the grading activities.
include a filter over the sidewalk
a sediment basin in the drainage
and hay bales at the bottom of the
5th filing Swale.
The sediment basin is sized to accommodate 348 cubic yards
of sediment. The bare ground covers 3.03 acres, and the sediment
basin size is larger than the 300 cy of available volume required.
at 100 cy per acre.
The combination of the improvements for sub basins 1,2 &3
yields an Effectiveness of 81.1 :, which is more than the 78.0
Performance Standard required.
In sub basins 5,6 and 8, the area is 2.89 acres. Of that, a
relatively large area of 1.33 acres will be sidewalk and paving
(there are lots on only one side of the streets in much of the
L
SUNSTONE VILLAGE 6TH SUBDIVISION P.U.D.
PRELIMINARY AND FINAL EROSION CONTROL PLAN REPORT
area). By planting the disturbed area in temporary crop cover
after grading, an effectiveness of 82.0 : is achieved. This is
in excess of the Performance Standard required.
To minimize wind erosion from the site it is recommended
that the northwest perimeter of the site be provided barriers of
some type. Snow fence, hay bales, windrows perpendicular to the
northwesterly winds would each be a helpful improvement.
The construction schedule for the project is to begin
grading (with the sediment basin and drainage swales to the basin
being at the beginning with the grading activities) in early
March, 1992. It is a relatively small phase of development, so
it is anticipated that grading should only take 4 to 5 weeks.
The seeding activities required should occur in May. During
construction, adequate watering of haul roads and areas being
graded during construction should also be provided.
Standard Form C Follows Form B to identify the Construction
Schedule and timing for installation of erosion control measures.
The erosion control measures should be maintained by the
developer until the majority of homes and landscapede lawns have
been completed and the developer is allowed by the City
Engineering Inspector to remove the sidewalk culvert filter and
the hay bales, and to fill in and landscape the sediment basin.
RAINFALL PERFORMANCE STANDARD EVALUATION
---------------------------------------------------------------------
PROJECT: 3u►J5T-otJ E UI LL AC g �j' STANDARD FORM A
COMPLETED BY: O L,Ip DATE:
---------------------------------------------------------------------
IDEVELOPED ERODIBILITYI Asb Lsb Ssb Lb I Sb I PS
�SUBBASIN-+ -_ZONE---_-(ac)(ft)_- -_(%)_ (feet) I _(%)- I -(_)--
I .5.3 3 1 6Z 0 i), v 1 (0Z o! I, 1 19. 6
'15, 41a llg l�o�era�� -Z63 1 ego 1 6.8 { 8. 1 0,? I -7�. 0
u
DI/SF-A:1989
EFFECTIVENESS CALCULATIONS
PROJECT: 6UN5'i0 N� 711-t-A'{GE (CTH STANDARD FORM B j
+COMPLETED BY: %LLD DATE: 7-1-21 1
Erosion Control
C-Factor
P-Factor
Method
ValueValue
Comment
R"D5/IA/ VILKS
6.61
---•---- ----------
110 I
GRAVEL FI L.'TERS
1.6
6"a
5-rAA 1v BA LE5
1.6
6.8
'T E MPCROP
o.y5
1.6
E5TAB,GRq S•
S�.0tMENT RAP
110
----------------------------------------------------------------------I
MAJOR I
PS SUB AREA
BASIN
(`%)
I BASIN
(Ac)
-----
------
`
------
5.33
--------------CALCULATIONS
RoAp6
b.'eI RG �ST,4e,6RASS / 49
I
-76,b
.C3ARI: GRouND 3,D3Ac
WTD C-FAGToP-27= JEO,01 X0.91)+-(419Y0,67)
�� /
�'VT') P FgGToR 0.8xb.8X0'5
EFF=�—(D,5':?.x0,32]fl o D 8 1 ,1 % 6 K
Avo-rE: U51Nr- GRAYELA"r
5iD`=WALK CuLYER'r�NAY BALES
Ai NE GORNF-P` da SEDiAi5&ST I
13A51AJ IN EAS'rERLy pRR/nJA(gr-F
RoRD-5 J,33,4G CSTAB GRASS 0.5A
/ fZ£ GRoulll� I.D614G
WTD C'1-AcToR = �(0,6111.33)4-k.5X6,6i
E F F = LI — (6,38X I,o)]x10o = 6Z,o%
AFDD GRDUiISb CovER To D157U► 6-5L
AREA
WrIDC—FAcre2 = [(D,o1%X.1.33)iCO,SXo,o7�
EFF=�—(o.ISX 1.0��YIDD—SZ,OxoOK
I0D Rol�IoN WILL- BE AtipRu75.5E4D C31 TFfr= GRoui
OVER IPLAqTING iA NO BARR 1 E-R5 ALoNG'T+JC M6J?THW&5-j
1=RIM+TER 10r TNI-- 517-61
---------------------------------- ------------- -----------------------
DI/SF-8:1989
2.89
to
CONSTRUCTION SEQUENCE
PROJECT:. Sutil5'T[1 w F V LL L 4G 1= 6Tfi Fl L I N 16 STANDARD FORM C
gEQUEYCE. FOR 19 9Z� ONLY COMPLETED BY: l?L p DATE: 2—8 Z
Indicate by use of a bar line or symbols when erosion control measures will be installed.
Major modifications to an approved schedule may require submitting a new schedule for
approval by the City Engineer.
YEAR
1r19Z
MONTH
IF IMI�►
i��Iv iv l ISI
---------- --------- ---------
OVERLOT GRADING ✓------E
----
------------
-------- ---------------------
1iT1 t-i-r'Y 1 nl5-rALLA f 10
✓
�----�
WIND EROSION CONTROL
Soil Roughing i/
.....
Perimeter Barrier
Additional Barriers
'
Vegetative Methods
Soil Sealant
Other
vi
RAINFALL EROSION CONTROL
STRUCTURAL: '
Sediment Trap/Basin
f"�
✓
Inlet Filters K,H
Straw Barriers
Silt Fence Barriers
Sand Bags
Bare Soil Preparation
Contour Furrows
Terracing
Asphalt/Concrete Paving
Other
VEGETATIVE:
Permanent Seed Planting'
Mulching/Sealant
Temporary Seed Planting
Sod Installation
Nettings/Mats/Blankets
Other
011JID
-------------------------------- -------------------------------------------- -------------�
STRUCTURES: INSTALLED BY �%V�[_pp E r2 MAINTAINED BY
VEGETATION/MULCHING CONTRACTOR
DATE SUBMITTED
HDI/SF-C:1989
APPROVED BY CITY OF FORT COLLINS ON
40.
DETENT/oN
POND A/0 1 .
lop
.41
% % A Q,-- -
-
1p
4.17
000
/
Q
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/
e
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tv�-
&EA%AI O,eGA✓AgB PNOnJ QB74/4
5tGT/O.J C-C
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e' k £Nv'
Jlwvx< Cfuvicer /Auer /toTG0 rf4U
ron]ff)
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.av9s � of ,:3dkAR7 eRe
k ee kFf l,]d3 kw'..
Ga]E Oeroka A.w k 4
ouk/�nkA. GarcE:�
Gp.JGILJE y/e/✓G6f P✓ �Gl/2
zz�e eRe 4ESN%IAR
eAm &6,1 AA6 4,A)
A -A Kts.)
AN1 • e.316
✓ • 0455%
�tiR��-c .<.a au,.am ,a✓
eXER
av w .L.efl
OR p,y9 I ........
p, ,y.q' ✓. oRs�
Oey.,/j . BB o9h
able Mw y4aR..e. 31cfs _i e
Gu /✓/ne 4•e.Gp+d•6ch m_ eo'
/ech/
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a1f11 ,L.S.R.
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/A:.6' T �i JG S.vwcE (n.kfi
A/0.6OceP S/(.f/O.aI O'G
N• ofQ.H. 1IIL��a''L
cT
A.e
INTERMILL
LAND
SURVEYING,
INC
N CIb4u0
SUNMERSTONE
/ COURT
0 L9 w io0
SCALE I'=5O'
CONTOUR INTERVAL: I FOOT
LEGEND
MR CONTOUR. WSW---•
MtA] Gb' p.� Ir
F M•.e Y:/Yql.
i EXIST CONTOURS _�At1W
♦RO4160
PROP. FINISH [
SPOT ELEVATIONS jo
r.. MINIMUM TOP Of DS B
/ FOUNDATION ELEVATION
\ FLOW DIRECTION ARROW
GAb4V.J �ieMTLOL F
\Y.
' 1 E A XVOPO�W IE VILLAGE
IERIFILIN
VILLROE 6]X FILING •
=e / 3 YERP rW AM
SIN NER O/NM TIES OF IM I£ 1 R-YR 1 IW-Y O a-YM 0 IM-YR IIEPOINTT
msi mnm COVLEN- CO EN-
/ ]RA]101 TRA71M
ACRES) 01N) IMINI. IIN6e) Un/R) ICES) KFS)
/0 SITE
1 I.10 0.5 I4.3 14.6 a.9 6.0 1.1 e'0
a - SI] 0.5 I3.9 16.] .9 6.5 3.1
3 1.15 0-0 10.0 13.3 34 6.3 01 S.0.3
1.IS 0.25 .6 11.0 20.0 LS ].3 O.1 6.6
S IS3 0.6 11.0 0.0 3.6 ]4 I.I '6
1.36 0.6 10.10.0 3.R ]f 6'6
.40D10.0io'702,90oe :o 2.5 .2 0:
OlSITE
-1 O.w 0.5 15.1 12.0 23 6:6 3.9 12.6
0." 0.5 10.0 0.0 3.3 .3 .f 1.6
O.RO 0.5 I5.1 Ip.O 3.1 6.6 0.® 7'9
cm PINES
I AN
so' 6 .a 3.77 0.6 13.1 11.6 33 6.] a.f 19.9 A
93 .nn 7.61 0.56 18.3 .] 1.9 6.a '].n 30.e O
OF 1 .94.
P 6 9N
45.1 1.06, 3.19 0.63 169 13.1 3.0 6.5 4.0 16.3 [
3 y3 '10....
�Xhilar
GENEVA HOMES I OVERALL GRADING DRAINAGE
8 EROSION CONTROL PLAN
4,E-,N AE4L / ?�r/9 t.
NA
ELT XO IWO 01 SNLE 6 RO,LCT N
7 1 8 1P-91-1700