HomeMy WebLinkAboutDrainage Reports - 09/23/1993Wa
--a—AM ®� Final Approwed Rep,
1704T CoLufti UTEL rms
DRAINAGE AND EROSION CONTROL REPORT
LOT 11, CREGER PLAZA SECOND REPLAT
PREPARED
FOR
COMER CONSTRUCTION, INC.
PREPARED
BY
STEWART & ASSOCIATES, INC.
103 SOUTH MELDRUM STREET
FORT COLLINS, COLORADO 80521
303/482-9331
SEPT 21l 1773
DRAINAGE AND EROSION CONTROL REPORT
LOT 11, CREGER PLAZA SECOND REPLAT
-SITE LOCATION AND EXISTING CONDITIONS
Lot 11 of Creger Plaza Second Replat (the site) is located on the west
side of South Mason Street and about 600 feet south of Horsetooth Road.
The gross area of the site, including one—half of South Mason Street,
is 0.738 acres. The site is presently covered with some vegetation. The
Burlington Northern Railroad runs along .the west side of the site, and
approximately 5000 square feet of the railroad right—of—way contributes offsite
flow to Lot 11. The southwest corner of Lot 11 is presently a low spot, and
runoff from the west two of the lot now runs.to this low spot, which
then drains to the south across Lot 10.
South Mason Street, which is improved with curb, gutter and pavement,
lies along the east line.of Lot 11. The center of Creger Drive is located
opposite the southeast corner of Lot 11, and the center of Creger Drive is
the high point of South Mason Street. Mason Street drains north into the
Foothills Basin from the high point and south to Mail Creek from the high point.
Lot 11 is located at -the break between the Foothills Basin and Mail Creek,
but it will drain to Mail Creek via an outfall pipe into an existing storm
drain manhole located at the Creger Drive and South Mason Street intersection.
This manhole drains south to Mail Creek. The runoff from that part of the
South Mason Street right—of—way located along the frontage of Lot 11 will
continue to flow north to Horsetooth Road and the Foothills Basin.
DEVELOPED CONDITIONS
After grading and development, the site will drain to a detention pond
located on the paved parking lot along the east and south sides of the building.
The building will be located on the north central portion of the site.
The developed site will consist of 15,000 s.f. building and pavement,
4,640 s.f. landscaping, 9,500 s.f. roadbase turn —around, and 900 s.f. driveway
pavement on Lot 10. The developed runoff coefficient will be 0.63. The
building will be a karate -school.
The parking .lot pond will detain runoff from 0.669 ac. net area of Lot
11, 0.115 ac. offsite area from the railroad right—of—way, and 0.021 ac. of
paved entrance drive to be constructed on Lot 10. The runoff from the west
half of South Mason Street adjacent to the site cannot be drained into the
detention pond because the high water line of the pond is above the flow line
of the street gutter opposite the northeast corner of Lot 11. The pond high
water line elevation is controlled by the grade of the existing storm drain
in South Mason Street.
We hereby request a variance from being required to divert the South Mason
Street flow into the Lot 11 detention pond. This street flow quantity which
is not being put into the detention pond is being partially compensated for
by the offsite railroad right—of—way runoff which is being put into the pond,
and also by the 900 square feet of offsite entrance driveway pavement which
is draining to the pond.
Lot 11, Creger Plaza Second Replat
Page 2
The design of the storm drainage facilities complies with the City of
Fort Collins Criteria for Mail Creek Basin, which specifies that the detention
volume be the difference between the 100—year developed runoff and a release
rate of 0.50 c.f.s. per acre of site. We have used the net site area of 0.669
acres to calculate a release rate of 0.334 c.f.s. The required detention volume
calculates to be 4,732 cu.ft.
The proposed detention basin will have an area inlet at the low spot in
the parking lot which will be the pond outlet. A restriction plate shall be
placed in the area inlet to control the outflow to the allowable release rate.
A 15—inch RCP will carry the outflow to the existing manhole at the intersection
of South Mason Street and Creger Drive. Runoff from the gravel turn —around
located on the west part of the lot will drain east and then onto the paved
parking and then into the detention pond area.
Lot 12, which lies just north of the site, is presently being designed
for Mountain Plains Constructors by Dennis Messner. Lot 10, which lies just
south of the site, is undeveloped. Fill dirt.has been placed on Lot 10, so
its central area is slightly higher than Lot 11. This is shown by the contours
on the included plan. There will be a slight berm placed along the south side
of Lot 11 which will stop any offsite flows from Lot 10. The outside edge
of this berm along the..south property line and also of the berm along the north
property line will drain' offsite; .but the area draining offsite is small, and
the berms are not hard surface so the flow quantity will be negligible.
A shared driveway will be constructed between Lot 10 and 11 (the site),
which will amount to 900 square feet of pavement being placed on Lot 10. We
have sloped this 15—foot by 60—foot asphalt strip to the north so that all
runoff from it will go into the site detention pond, and no additional runoff
generated by the new hard surface will go onto Lot 10.
Calculations for the historic site runoff, allowable release rate,
restricted opening size, required detention volume and provided detention pond
volume are shown on the included sheets.
EROSION CONTROL
This site is in a moderate wind erodibility zone and in a high rainfall
erodibility zone. This site is small and will all be overlot graded at one
time. The grading will form a ponding area which will act as a sediment trap
during construction. A straw bale filter shall be placed over the pond outlet
before paving, and a gravel filter shall be placed over the pond outlet after
paving. This outlet filter shall remain in place, to prevent sediment from
entering the storm drain system until the project is complete and erosion
control measures are established. The site is narrow (100 feet wide in a
north —south direction), so construction of the building and rainfall erosion
procedures will provide adequate wind erosion control barriers. �p��plilYf�i��
This report complies with City of Fort Collins Criteria.
a
*a 4502
Phillip Robinson, P.E. & L.S.
:�'•.`P0y.o F & tie.''
U U J U a• U0 �`U t• I 1� r. ;
F N S
oU u o o rontle�I �1 oo iyhthawkC\ o �� 4iP m
v Cf.o by Dr 1 �l I w - lmdo °P Q v p o
o a a E �u C t. ❑ .`
U D m
U W. swallow Rd. E. Swallow Rd o o
c o v
0 0s� . 2unr I o Bo olink w, co
0 0° co Cir• u
pro 004 G�' u C . Ro in'Ct. (: \\5 Pkw
T e � Q 1K y•
i 90° o a�Qi B� Y Card Ct:'.. I o°•
c F
Homes agle rn
v .�e ° o Ave, C °d.... C\._ _Bluebird f°°
' a Oc1�, fit• pK w
n ��' v
Justice Dr. m
Cann/� ¢ E. Monroe
Dr. abo v doe Ave. Ave.
a\1C Affirmed Ct Sic
o �.
o p\. W. Monroe Ave.
kE
oFE
Cx
3 E
W. Horsetoot Rd. -'-d +..N t
> �, q - n_
I . ,� ...\ �� 3 S/o, pritl C,
Arbor Ave. = a,• ,�
c � Aoo �,
0 t a^ a ro Cr
Bonita Ave. o z
o- O t Leeward Ct rJl )F
cos �da o Ave: Jasrndn Dr. = ;
CA Ge t e I \ BoWine Cl.
0
o� ' c'i o Dennisonone
o
ru` Y '']' (� o o�
8 moo° t Cf. ble m m u m 11 1-,. �� yQ°�^ ?
c u o <
WMler o a C IbOard ° F° G`' Crawi
ct. c3 ro AI �' �% I ` G o\ t Nest
Dr
gg
Marble Dr br.
�oposh St. E 4 I Boardwalk 14 Ln.
High'
m Point =
o
Butte Pass Dr. O uu m tarlin t ` r
O� 0 i °'i a � Greal Plains Cf. h I .. / o�0r G c
ui I O
u t9vo U Trou\n`0n?k 0�z vc`i
soc o c itemoel ~ Trout an P v
aJk
ccLL H o •' I I \ 3
o emm in9 ear I I.Thr skier o c C /)
Deer Crecy Black Gran f o S 4 0 M
one- Hawk CCt.
�• a r. o $ I ?e I/
or
S rkY t. Y Lane bunN e ' vi Pavilion /
o
c C�� _ ( `
U v,4, Ln. ^ s Owl C�huk `:� o
CG
ii „ Ct. �. - Kedein n i
kk o c o in c ;,, Dr.. , m
bin in Nbodland Nvr Towhee
-`
Vl C1IVfTY Iv -��
Nickl us a
/ rr= / 000 q Palm �� v
I St. ,
v o
t I
Rochelle Cir. %^
ato
s H Pa\n't o
STEWART&ASSOCIATES
Consulting Engineers and Surveyors
103 S. MELDRUM, FORT COLLINS, CO 80521
PH. 482-9331 FAX 482-9382
By: hl R Date: 28 93 Client: Co 4 1,er Cons-} , Sheet No. of
Project: Kara�e- er- plaZC' Zh�
Subject: --S-Vora U ra f'Ic
_�G_coss�_ ifs re�i 1 dui SiC _� Hai- 'lli _ ' I 7-3 /4 -' sF 10.669 i4c
Tv TA L: - ! U. 73 6 14-
- --1
4r i
;3Z0' 0.5� d,
3,4'�I•,
I i ! i .S 3 � i •I i i_ I I f
Qi r4IS7 - +clA _ i(0-10)(�.25)�0.73�)
I i _
aloa 141 s-) G > G1 9 �/.2���4, .Z�)�3.75)�0.73�� O. 69Z' G1 s
0.15GFS ,PER ACR;;
1066 AIE7- ',9RjFA 01:
�0.663�CO3reea� I
1 I � i t
re I ee,se ra :c 4 0, 33t. r-4-1 r-
Ic
r ,
0.<e! Qr-F-I.c( �privyCA� IL/= 0. :Z 1 - (� _i A V
0,33 4-
'Ofir! I S
!.GpCJ-e Ili 4ee
/
cj►� d/JCn? i^j
U , �j I
, I � I
I ( I
i lrei Gam.'
r
STL V VARTKASSOCIATES . PH 482 93 1 F X 482 9 $OLLINS, CO 80521
Consulting Engineers and Surveyors.
By: nl 1 Z Date: J 2d' 3 Client: Co 41 e r Coh r�- /n C • Sheet No. _
Project: Kara � Lo I1 Co'C�2r Mato, 2rt— Kcal-�
Subject: De -i e J i c n Llo me, ffAfg V ire d
of
j At'eo.l..
Flow+ui�.
Z- ��LI-oi
illl= 1Zi/ q
SF1 I !
�_ O G6t /�c
_!
I i Q Sits raiihvw�
=, So00
SIB
I
P�,,eJ!enfrCwnce dri've
on W 10 =-900;
SP�t�
�eve ope
0.8o5
Y IZai,
rcad �
5-000
SF I W ZU
1b1�► I�!p„�1-=15900;
rod, � bG J e
a
5 5UU
SF 1 0 � 50
�i
ISoda(o•ZUl
t
0.9��+(¢G4G1�O.2�
(9�aV)(o.s��
I
! T j .I
I
c Fcsa'. ; I +� I.
!
i ✓ I
f
IZeI �c r c
I
' Dc %e��; oh
lU
7.0
ZGG
'20 '
S 2
( ;0.6!34-
! 3.301
I
2,2,Z
1
I 532G _
i
_' �UZ-
sa E
3,0
j j,yo
5-70Ci
-(G i_
i
2•< !
5939-
-I
!
!lio2
+ j ¢-732 �—
76 I
2. 3
i ,
;
! l i'J-(j
; 61z9-
4-0 2-
' 9-7ZZ
G?3q¢
4Z�
.C(e (
I
jZQ'U�
I 4Z I4-
18U �
!
l 01>'
i ?
I
! I 0.6 7'
7110
i I
13 6 U7
I 3 sF3 Z
111
-
lC.
:I�!�IQ lilli f.�
, r
STEWART&JkSSOCIATES PH 48z 9 31 FA FORT
COLLINS, CO 80521
Consulting Engineers and Surveyors By: P/jam_ Date: Z 3 Client: Cogim'- Sheet No. of
I fr,
Project: _<a r-GY-C wC f t-- to 4- l ( cr-e.= Alt
Subject: 0e4e n4 l o h �po ^ � �,.� St'
VOL(/M F 0F�
17-,)4-I L/Ply~
1
1-�
3J4,V
I
{.
G 0 / 0 Cv F-T
�337U
✓01(//n e-
I /00 r
`�
I/-Wl, �' , �608 �ajZ 3C.5
i i
35
I
L
I
,
I
I�
I'illllll
;';
PROJECT:
COMPLETED
DEVELOPED
SUBBASIN
To TAL-
sl7E
RAINFALL
------------
LOT /I Cr<
BY- ---- ---
IERODIBILITY
ZONE
µ'S
PERFORM
jer Plg
Asb
(ac)
mm
CJ.G90
H�
0
a3
r'
he
w
WE STA
z a Su
Lsb
(ft)
IDARD EVI
.off fZe
Ssb
M .
UATION
oaf- ---.
Lb
(feet)
3 Zo �-
----------------
iTANDARD FORM A
)ATE:--
Sb 1 PS
M I (o)
64.377 72^5j
I
EFFECTIVENESS
---------- ---------------------
CALCULATIONS
7
PROJECT: Lo-t /! Crc�e�
P1 az�.•
-------------- --------=---------------
Seca�d f�ePlaf STANDARD FORM B
COMPLETED BY: 1?!>t
UAIE:
Erosion Control
C-Factor P-Factor—
Method
-------------------
Value
Value Comment
----------------
-BQ re.
------------------------
•— -- oval e)- �1 I �c r ..
- .... .
too
raAdbasc 71/r�-arovne�
0.1a,
•I,00
-
MAJOF
BASIP
TrlL
51TF
P S.
a
io )
72,5
SUB
BASIP
AREA
(Ac)
o. C9
CALCULATIONS
------------ --- - ---- -----------
0. G
�a �e •5o r )
c Onr- b��� �ac� G, 03 A(-
ro ad bosc -urn- ar v%/ O.
gravel. base. in �t2W 4c
Q�
G = 1U.186J(1)t ��.133XO.0/)+(o•16S%(•7)t(0.20G�[,
vGy
c- = 0133. .
..F = 0,80-
FFF 0. 8) x 100 73. 6�
0
i
CONSTRUCTION SEQUENCE
PROJECT: -_Lo-r // rr -e r 171oza 2e-r/niFelp(oF STANDARD FORM C
!ZFQUENCE. FOR 19gLl± ONLY.: • COMPLETED BY: '_-pf7Z- -DATE:
indicate by use.of m 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
MONTH
----------------------
OVERLOT GRADING
WIND EROSION CONTROL
Soil Roughing
Perimeter Barrier
Additional Barriers
Vegetative Methods
Soil Sealant
Other Fdn•
RAINFALL EROSION CONTROL
STRUCTURAL:
Sediment Trap/Basin
Inlet Filters
Straw Barriers
Silt Fence Barriers
Sand Bags
Bare Soil Preparation
Contour Furrows
Terracing
Asphalt/Concrete Paving
Other Roadbase
VEGETATIVE:
Permanent Seed Planting
Mulching/Sealant
Temporary Seed Planting
Sod Installation
Nettings/Mats/Blankets
Other
STRUCTURES: INSTALLED BY MAINTAINED BY
VEGETATION/MULCHING CONTRACTOR
DATE SUBMITTED APPROVED BY CITY OF FORT COLLINS ON
H. SF-C:1989
STEWART&tSSOCIATES 103 S. ME482-9331LDRFUMAX , FORT COLLINS, CO 80521
PH. 482-9382
Consulting Engineers and Surveyors
By: Date: Client: Co4fer- Ccly)c�, InC Sheet No. of
Project: LVT r- P, Cz zc,, S_e_CC;KCJ_ F/.C(A
Subject: rO-5)0r) C O'n 0/ GOyt
00
'300
i"4
L.,
off'
CO-+
C*1
j f x� nl u rt co SO
ii�
!
��
!iii�i�i�iii
A
F
N VIxo) .c300)
II
Way At aft,
p
AIR Aft VAR
tl ,fat)
"Aft
(y1;
O¢
Q
/
�'
W
/
f /
g
L
!
w
g
_
/
2
T
I "�
MJ
j '
We
O
We
IX(30)
-,: , —
ISG
I
art
i
7 G
.pan .�3fn >I3f31
�a
�A
N ale N f0aW 293.12
/
a
\
/ON
/
1
l
G THICAVaNa
CTEP
TORKI
pAooASE TURN
ARW1'O
/
\\
SI'33f)
MIN. BO
OIAMETLR
QU.f)
/
______________________
ss j
A
±
v
\
Si00e
ITS It
FLOOR = 503Z50
G is
TUATTION ILO,
,Of
1
M_ICYN5T
oa
A N T
NL
3S.0
INV SLOW I
xv
43L4
1
p„)
�i0,
eauoSrRlu3 s GLRf
z
TYG MICO
qi 1
'FC`
34.1
I.
�3G3
/IJ
--
G
OY,
DEALT e
N.
At
oO
Jf
I
Ill I
L&j
w
I
a
h u
L-r.L
Ey
2 'llco
OI:
{a r.IOGG FROM PYVEO _
O FIFS ITE RUNOSF cRON Tg
V RVELOPoO LOT ;Y 3SVTRTO` ENRA14Nu To N LOTb A --�/ Jl0
ESYT a� N To 11 OfT ypNP ST
�ovOgRep OAT THE ROAR _ �100 F FbVeol �'� -
/ / I F LOT _IOI
O all_ t — _ _ — DETGNTY4 POND
/ I f193L j OVERFLOW RT 42y 3CB
e ',� z ^roe wL,lum, fb
R`
/ a iM1L � iev G'or1; 34G
II ,(SV ]i '/ TIS45i ♦I�il Iyi
(3il) / ,ISLSJ iA5t11]` fl]fF) I s1
� � . R Ina IT
LEGEND :
- - -----. _ _ f. __ _._E4•i-__ 0XISTNVc cbOWI
3L-- GIN 6N CO NTOVT
ESISTIN6 500T ILLVM104
-- • 3G.] Grr.i lir. SPOT HLX✓ loam
- - -- - N -I - SHAOEO AREA STURM of pCTENTON irNO
of
- OOVNOg4Y OF OHfNION 4aNOESMT.
mmammoof
Z — .
-—s- _- ORHINAGE SUMMARY:
1. SITE ORgrNS TO MAIL GRCCK 3ASIAI
Z- 4R053 IDTC AR[A_ O. r3B i10. NET SITC a O.GL)KJ
J. Huro arc- o.w
__ -- - _ --'- - -- 0. OEVGLOPEO c i O. Gz
R -IP- S. RGLEASE RATE• O.S CFS/.f[ c �O. SJ�O'G%Ja O.l3i CF1
C OETENTON REQUIREq = 9465 cV. FL
2 DETENTION PROVIOCpc GOrO ZV. FT.
of I
76
a ' GRA3560 6fEM lywtE 0O \
To 19M,a D.O \ ORMSEO C[RM
F FL=36.0 \FLLOOS'3Ts OP aan
1 >o
ExIfT GR:%o' 3$ TS J TV iSO
n ycF
3ENCH FOARK = 5035.33
NE.OB F.H. sW COR. -
�LSCTOOTN AI mii
SECTION A -A SWALE r9LONG
NORTrN srpE OF SECTION g-P_ (S E RM_BLO(JG__
(; UILDIN6 SOVTN PROaERry tWE
so
m
RIMOVC Eb Ht CVMT A$MY NfClffr aY
REPLACE PVMT
INSTALL
IT PEN LIIICS LINES NM
T✓RIGµ RIM[rvT:
mgsVN STR{Er r
NOS TAVIL FROM]s r, bat
POINT
ur AT THE J. G• Iall P4
__ CR EGEct DRIVE
All L
$ALL
A. off Coeval_.
l.O MM
..), uenaum it m mm..6'Al.p rroTn Ns aATIe.x.n.O-
.M.... 1be.CIO V91mr.
Rq, 36.0
itYl
HSf
rNV4i.ar
_____ MXM
... -
In__I_/IOIN I_o
a IA___I_n___I_S__IJI
...
worm. m
____
AlIT
fit tight"
PMVI
Altnal
Cal LrwLH
RAINFALL _.. m.Ts
11 All
Aftl
Im fill. AIR, Kati. `n ':wiltial
lawLbe A LL
4 aft
I.. .... a i'ek. flatrrT e,
W ...xun.
M.
I Calla'. J..' N..1rr
At
Way:: w:..L,.' T1. Irf. >..I..II
V N. XNi. ...n. nln IOF a Lm 5 flat na..amn.v I. 5.5 (.at..al
a
m. , ,. 51.._.... N « ,.
n LMlrtmol urarm n CITY OF rtn mu "al., ao mat su .n avwn
rouv.cnw
EROSION CONTROL NOTES]
I. THC cAbnr TR ACTOrs 5Na LL GLEAN OFF
MVD NO PERRI5 T4q C(EO ONTO P/,VfMENT.
2. p S' RU at STRAW !FACE AOFf WLET FILTER
TO VEMENT INSTALLATON 044CH
51OAyL 6E III A ORiCVEIL )IJLET
F)IJI AFTCR PaVIN6. FILTER TO REMgw PoR
OVKp l*O OF PROJECT CfmISi RVCTION.
S
u
�
2
Z
q
Q
W
Uq
NU
u
Q
Wp
OeiO
At
3"
kfa
a
Q �
lu
0
��
D
QW
L'f-
R
Yo
yya�0
U
r
O
J
ONE Of TWO
A
On
w AWI37
mor
UPPOw
.h nOPPROPPOT
TO
�•
mcmSPECTIVE VIEW
ROW On On
Clio
NO
w_
SIECTIOg A -A
v IT
Mrrq
Ea
NOR ur•. r. mri
NEW DRIVEWAY APPROACH DETAILS
VERTICAL CURB AND GUTTER
CITY OF FORT COiCOLORADO
END SEE91NG
DCECION
WE EALE WE' UNION 3 LEND 0 On.
IL WECCE 0 Owl
mrnox ALA ..,,.a,.=arm,.R ..RcOWL wWm..........".
nw...... w....mm nr.
IF IWITY POLL LY
.........[.�.
..r �a ,..
P1AN LIFW.1
POP
uw w
CRUET SECTION
OWL Ill EPPLEM LOT .1
-POPE
-1 T—CaNR&a[1
Urr�YMwl
['�.11
T Ruxvw TTwC CEO,
u�... _. T—F
R.vR G�wei FiN..
FEE WE
9VCPANA A
.w=�•�xw. x[...... x...�am AREA INLET FILTER
DOE
- 7
E � i
iT
9sIT
�l
_tt 3s
rie.i4
"n
is iA�33"_
Cn r 3
si
is As,SP
s,ID
Ai
ij:g.ira"
lye : Isis e;
a� _
a tag E?cPii
wAw
II�IIIIII.
R
PLAN vl M
as sal
[m.n e.[�,wKnaN YA ...
ITIVIIIEVE
MRmmwa w.wa wum�ilaen
�vlm IMIII LED /Z-
P w¢ LID
1m1kIF BITTER PIT MILE
�m RICO
0I OPT
III NICOLL In I
0 PLO I AND OF owl PI 1.
In WE 11 IT I
TWE
RECEN
if LEPLELTIPI .I.
o
maul 01 .,s
wl�.
PER
b
COMPUTED' W
w N•
lv
#p
STANDARD EXTEPIOR SETTING
FOR 'J/dam 8 1� WATER MFTEFS
CITY Of f7.COLLIN9,COLORADU
wmm n.
L LET
= =117 7
PEROT
TIE POLL IrW I
PRO I Dr PER I IMLLUL
IMP
NO
...,vxYET
OWL
IT OR WILIMARY PLY LE
SEWER JOINT ENCASE MENT
u.�smr m mow° SEWER U[T11t5UCTpN r nay � PLTLY
a
N O
M.
Ff toILL
G
� a
E
P