HomeMy WebLinkAboutDrainage Reports - 05/27/1990 (3)n
STORM DRAINAGE REPORT
FOR
ONE PROSPECT P.U.D
PREPARED FOR
W.W. REYNOLDS COMPANIES
APRIL 7.•1990
PREPARED BY
STEWART & ASSOCIATES. INC.
STORM DRAINAGE REPORT
ONE PROSPECT P.U.D.
SITE LOCATION
One Prospect P.U.D. is a replat of Lots 1, 2, 13, 14, 15 and 16 of
Prospect Park East P.U.D. It is located in the Northwest a of Section
20, Township 7 North, Range 68 West of the Sixth P.M., City of Fort
Collins, County of Larimer, State of Colorado, and is bounded by East
Prospect Road on the north, Midpoint Drive on the south, Specht Point
Road on the west, and Prospect Parkway on the east. The site is located
in the Spring Creek drainage basin.
EXISTING SITE CONDITIONS
The existing site is covered with sparse vegetation, and the surrounding
streets are all paved and have curb and gutter. There is an existing
drain swale running west to east through the site. Concrete drain pans
are existing across Specht Point Drive on the west and across Prospect
Parkway on the east, which channel runoff water into and out of the
existing swale. The entire One Prospect P.U.D. site drains to this swale.
There is no storm water detention provided on developed sites or proposed
on new sites in the Prospect Park East P.U.D. development. This is
because the development is adjacent to the Cache La Poudre River, and
drainage swales have been provided to carry runoff to the river.
OFFSITE DRAINAGE ONTO THE SITE
,IDvJ�Tract "A" of Centerpoint Park, which
wig a developed in the future under
d°� J across the One Prospect P.U.D. site.
surrounding streets which will contri
acres o is total will drain direct
acres to drain thr
is presently undeveloped, but which
HB zoning, drains through the swale
The area of Tract "A", plus the
bute runoff. is 13. acres_ 7
the One
reek, leaving a
P.U.D. swale.,
Un�,,�� ��us-h &4 Und r � o4s
According to Engineering Pr essiona7s March 1988 Spring Creek drainage
study, the 100 year storm,will produce more flow, by 75 c.f.s., than
can be passed through the Burlington Northern railroad bridge. This
71 c.f,s. overflow will run southeasterly along the west side of the_
Burlington Northern tracks, and will cross the tracks in the vicinity
QL Timberline Road. Calculations on sheet 4 of this reoort %show that
17 c. f, s o t-ie-15"c, f. s. overflow will flow to the ea
Timberline Road, and will possibly add to the 100 year flow thro
One Prncnact P U D swale. )heet 6 of this report is an aerial
of the Burlington Northern railroad ine im er oa
s oa eva ions o —IlieF`5�7road and pavement. ,
DEVELOPMENT OF SITE
This site will be developed as buildings and paved parking lots as shown
on the plan at sheet 10 of this report. The site has three drainage
sy b—basins. The west basin plus the offsite flow must be carrie etween
the west 'ldin s in a drainage channel. Sheet 9 of this report shows
e channel section and calculate low depths.
ico<y
eal8ns>
One Prospect P.U.D. Storm Drainage Report
April 7, 1990
Page 2
the central basin runoff is calculated on sheet 7 of this report. The
central basin plus the west basin and the offsite flow must pass through
t e draina a channel between the east buildings. This channel section
and the calculated flow depth are shown on sheet 9 of this report.
The third basin is t
This runoff will ha
runoff from the west
t buildini roof drainage and east
to-Abje-of f site Trom the west aeon
is calculation is shown on sheet
g wit
f1 ow
this
i
We have designed the site so that the offsite and onsite flow will pass
between the buildings without endangering the buildings, and also so
that there will not be a water depth of more than 1.5 feet in the oarki
lot.
Phillip I. R inson, P.E. & L.S.
/emu /" 'z a lazz)
'ado' X-fX
al D
rt�
yJ1,A/7 Z
AW--4 71)1 1;W �•�
L,JMPUTATIONS
Stewart & Associates, Inc. 214 N. Howes St. Ft. Collins, CO 80521 (303) 482-9331
By: PIE Date 5%2 Client: W_ VV, 1 e in o1 S' Sheet No. 3 of 10
Chkd By: Date Project: On e f TOSDec'i �. u. D
Subject-Sficlrr�, DTGl/IO�P — DSITP ��0�✓•
e lD,or•,
Gas r r are 9.7 G cres loee of t Q�' l�ist9l�llkl�
LORinS = H13 .✓
J :. G de✓els�ecl = 1 ,O�qs-r' I tl.Ld.
L _ goo"
' ol
_ r i 1 nG UU 5.'
�2Z- G i is)(t.G� 9I-7 ? Z4.O � r
i
q1ao= c
s (/:)(-1)(77) = 67,`1 c7S
Poss i fj'e S�l in Cf-eeI{i over-;-Riw 3 i ol--. ^/es o
wl,icj. will not Hass under �e
ra 0&0';
f roM En51^eer1n pro�ez!oIf pr-� o{ /�Grc%� i`1Pi�� fire
C
0�Ier- �o�✓ �vof-fir l5 S C- .
I i
SFF sNEET ¢FOR c1-:)LC.ULAT)OA1' Or �n/NE7zF 11-41S 7SG�f GOES
TO-%cc1 OFFS)TE
-Hi rovc3
CA
CC wa = 6 7. Pr✓s 17,
ProsPecf-
s wole
%,OMPUTATIONS
Stewart & Associates, Inc. 214 N. Howes St. Ft. Collins, CO 80521 (303) 482-9331
By: P Date ) Client: 1,J. V✓ Sheet No. 4- of/o
Chkd By: Date Project: _Q n 2 17 .
Subject S Or/%n Drc, na - S in C. «4 vLi& JaW ov T 13vrlr,7on tVoOern R.R.
! o p of ra dS n'04tiwtsi' o� Mb
f! I
,3Tv T/ 1 7
v i
�SEGTIjO/i
I4TzLJ Rfal L�
O 1 1 A 1 1 -1.
%I^verine IZd.
Per1r vn er v !be wee^
2..Z(/ x S0� U � X i . (� 1715
el
eni ��
!
// -`� . t'r, U en i n Jl%8er rck df
vse
0r4 icr
(c.. uP46 U-
O. Gh=03
ll -
p, 6 �4.4 '(U. sl
_I t
- �. 7J
'
�h
the 30 c-Fs t^Jtfl drain ,vj��ey- I�-�e rai�S be�wPP-� ��� fi�S
and will a/I re�r,ca!;� �,.ves}} aF Tt�^l�erl!�(' TZda� awe, dra?.
no r-4-6, to
=oliowlns is ovel 4;-\e r-O is
b� vse o4- I'kC wcl r !far vlc.+ Gt GdY3' 13N2/t
To rani /6,43 Qi'TiNSerirh�
H = 0.16 Max
7-he !1 c--Fs v. iO) aba rte a1i,, d„ f e ,Lle-Si- Sides a
u�d w►ll ciT'•a;i-A;n;or}h +0, SP �+ns cree,�f
t
7-11Kl e r l i Ae Re -
To r.4L ov�t<Fc ! PEtz 'ENG+NEEi`�IMG i'7ZDFI=SS/pn/f�l.S' TKEPOR7
75 - ��U-t 3'4- JS add'onCz ove-40pf!�S o�- il•e rc�)ir���.
/t is OL5:5 ecl 4h a4-' cX �- %earl + Z o -
rG'r,G�lr e' vic3 ; sl / aid fow rnv
- -v S,t7rJn-a Cr-ee. ; i-A _✓-eFo�r ,� , 44,
Flow Ona ii�roslpec
4ket-, V2- 1 or- 1-7 c S „✓il
»*41�1
try � X � ti+? /�- 9( - �'"� �• ��
of
2 N 49 0
X49//.QA.t 14.9
It
14r
too Pd/
' . f - i X�\ ' ; `� E L EV :of T7r.berlr.. e
49/2.
n. X q
�id Q.j �X 49/0.co
4/� t��.� 1
.. �, o i I z3. u> I. .�+a
14,41
Ay
`W1jy+� �"l{�'.1.� \ ` 1'�,II • ••�W �ry�' L��lr'ly*i��s
49/4 6
;�t E:
XQ,.•J.. W Mti'. �, '�� !� `! ,,•;.�r.�r �` r+J
w I>� 1•1Y({, � ,�� " �I 1 I I :4' tr' •, ��"` '• � b •• 9,01]'(�';. r�R
�4�� .Ir l �' ! � li�l'A , ( , Ih. rL s 1 i (S• Sh.` ' •'
,—'�; �� # I � i � i'1_.`r�I .It t I I ' r i + t � 1r.' r • { � , .�2 � ,` r '• ;•%��r,• T ..
wy It •; • • t'� I � a a t , � j( �2 � ���' • 16!� T` "-..A+, , .
X
;l; wok ► a� c r,. fit. ,��o �
�2.8' ►6.4k
�; ti
X 49/1. �1 5 rr:: I � � : �
i ') s '�= •' ;fit � � � _ rti= � ,�5' ..f iG�.
k
• 1 r i , r'��S M , •rji � 1 { 1?A 4t�/ �' 'f '�� �'f�" � � I � A,:, _ 7• }j�';*�4'•, �`k'�
.
41
if
to
49
�.�,. __... oF
I'
.. .Qr rn n l •
WMPUTATIONS
Stewart & Associates, Inc. 214 N. Howes St. Ft. Collins, CO 80521 (303) 482.9331
By: P11Z Date_Client:_ W- w• R evn ol�r Sheet No. 6 of 10
Chkd By: Date Project: 00 e 7rQ5f2 ��- !�. U,
Subject-S�ol'rx Dr ci/r)e
7-U-7,9L .AfZEA O.'F
sl51I7h �, (c
v�e c=r
�O�f.ZO1
O, YS
14 l s4-o r-IG ro'n o
(o Z'U
IQ = cry` �;.�ri I i
Gl �vv C-�1A: _ A106
U.2�) I
De �L/00 J ru no I i
1 9� T! OC/
GZ z G►/3 = O:9S�(3.1} (�r.GI) �_� iz;s,:3 �j�S
�10U-. G�cl/a = (► )� '7I� ! .�.� i= I t�O.Z cis.
I I
i
TO-r/+L. Dr.'va U, 0pFD 1 .IZ✓N0r-C 05 P1�0�PEGL PARKw/�1�
II�
41e �r arJ
�vi{ie �s.6 e4r
i 1ri
atov = 8¢.'y c:" 0: F4-t'i+C I�,Ivs ��.-� L S . �!rd•� SAC I ¢S.l Ctf
i
I
i
' j
AMPUTATIONS
Stewart & Associates, Inc. 214 N. Howes St. Ft. Collins, CO 80521 (303) 482-9331
By: E) K Date 5 -7 90 Client: Sheet No. 7 of
Chkd By: Date Project: 011 f Y JiOSf72C�
Subject S51'or-M Drainacr _ - _Ruho�P f-hrouciA s wcieS -6P eo/'n
S�✓c�(e be¢ ,,.ec, �✓s
I buil.
' S
y TV'evela. rUnc��
vvesl
Q ld - ¢�.S GTfS
0let, - 8�.� GTS,
Onsi� e cUn-I--r bvrUk,.I
i ...�
:.....
;
:
Li
7-c= l•Fr7�Lj .4 �: 99Q r i,;-
I I %G
IOU!'' nnin
QZ.. cii/�� - d,pti[S�•L�I�)() �i
5,'y
I Gfs
�l0 - Gj/ f �..1+��4�1��;Z•.Z�
.,
t j0•2
o 7A Lr-LO r1 _rL_t/ ^/.` Ll"dif
'1,73, V
I i
a-L = Z -+ .9 r
;
Quo= 4r.5-f10.2-
,I
;I
,I i i� ji►1�
i IIIi �jji
i i i I i i
i
I
�ii
�,
WMPUTATIONS
Stewart & Associates, Inc. 214 N. Howes St. Ft. Collins, CO 80521 (303) 482-9331
By:_P1TZ DateTClient: v-1- -Sheet No. _0 of�
Chkd By: Date Project: 0 r\ P PrOSDco<•i•" • (/ . �,
Subject S5hOv--A 17rarn9,i - %Zl )eI74 14'prvtlr�_s�✓c,)eS bed- ee,, �vi(c�ingt
svv(:R )e %e e<n sif 4 t)=�.d'r n s - tie✓eld e�i r`v�oTl
�jiil� II 1 i,�
7 c') itchn s
,
Ok w t Sl. 7 G r I I I I
Otw - /Oa, 3 c_:�-.S
r>nsi �-e; conri�c�
otcireS ILj=
�Uo` �! 4•4-�^,r`�
QiU GI/4d�
.I
ToTr-)L. FLot.✓f r"E-1.0s
L D ni
-31
C� wv 4 too. 3
I t I
� � I
t i' j � t i i i i i ! �� •
1 +
I
)IdI'n-�si-
WMPUTAT IONS
Stewart & Associates, Inc. 214 N. Howes St. Ft. Collins, CO 80521 (303) 482-9331
By: P ] R Date Client: _
1n/ W.
R e v n o/ S
Sheet No. of 10
Chkd By: Date Project: -
00 e
Frospec
P. U, (%,
Subject S
L✓
10o yr{ L
1 i � I I -� •.� z.i,s dip ,
n_ O OZO i I f
Z. fi i9 l 15., I , j P =13.4 1� _ ��P=
12)' 1 400 S)! �� 57, 7 !
1
Tr- cue f� Z.Z /� - U7, g- SF i P:- ►3.£f R -' P = n 3 �' c.Z
V (7a.s (1•z6)V3�?,vor)Yi : G:1 �t . ,a,✓� (17, 6 r io 6.1 c_fj
Tr d-cPP�4 = z. l � .•..ter 1 G . Z s i? =' 13. G 1z'
Vz (74.3)(!•Iq����o!ani)yZc 5.4 GjrV=�IG.2)(S.9)= 9S�t
100 yr retu(res Ja".3 el C�
r
Cc S4
1- - - -. [.o - -
ad
I o
Try deP h = Z= zS sF I i I 6.7-1--- 1,7
V; 1. 4-� G Rz�3 .S ��z = �� � I.16�'Yi
h oZ
v= (Zs)(S.ejt 14s �S j
Try d= I,5��/20 s;= 0.73
✓ SS
= �743)iU.73���(o.00S� %L ¢..3 G(_'� =I(1 i�(¢•3)= G4 S c_7 S
�
Td /-7 '
r` •• �= !`'2' 'S�= •�lt9 =0.fr7'
V 74-,3)(0. �� JZ�'�o.00s)'lz : ! �. =.�V: (r z c�1
! I
T►-y C4 1•1 H = :L3 SF, r< _ �jp = = r.U�
V= �74-.-3 1.0!q-)�`3 (0, 061s)Y; Z = i s r s ! G[ � /�r V= C S. 1Z7 <--VI
100 yr- re vI r-ef I/T If Lis efe�ore
�6
3