HomeMy WebLinkAboutLot Certifications - 05/28/2019
FORT COLLINS: 301 North Howes Street, Suite 100, 80521 | 970.221.4158
GREELEY: 820 8th Street, 80631 | 970.395.9880 | WEB: www.northernengineering.com
Water Utilities Engineering August 15, 2018
700 Wood Street
Fort Collins, Colorado 80522
Re: 237 McKinley Street Redevelopment
Drainage Evaluation
Dear Staff:
The owners of the residence at 237 McKinley Street in Fort Collins would like to reconstruct the home on
their property for personal use. Building permit plans are being submitted to the City for approval. It was
requested of us to provide a grading plan for the home and evaluate the change in drainage from the property.
The property falls near the basin line between the Old Town and the West Vine Master Drainage Basins. The
property resides within the Reclamation Village Subdivision near Maple and Shields, just south of Putnam
Elementary. Currently, this property is developed as a single-family residence. The subdivision would have
been developed under the criteria in place at the time of platting.
According to the attached calculations, the overall lot impervious area is increased by approximately 360-sf.
bringing the imperviousness of the lot from 18% to 24% including any future expansions of the front walk to
4’ from street flowline.
We have attached the impervious calculations for your reference.
We trust that this letter will satisfy the requirement for evaluation showing that the proposed expansion is
within impervious limits used for drainage design within the City.
Please contact Northern Engineering with any questions or concerns regarding this matter.
Sincerely,
Ryan Banning, P.E.
Project Manager
08.15.18
237 McKinley Street
CHARACTER OF SURFACE1:
Runoff
Coefficient
Percentage
Impervious Project:237 McKinely - 1518-001
Streets, Parking Lots, Roofs, Alleys, and Drives:Calculations By:R. Banning
Asphalt ……....……………...……….....…...……………….…………………………………………………………..0.95 100%Date:
Concrete …….......……………….….……….………………..….……………………………………………………..0.95 90%
Gravel ……….…………………….….…………………………..………………………………………………………0.50 40%Total Lot Area
Roofs …….…….………………..……………….………………………………………………………………………0.95 90%0.14 Acres
General Single Family …………………………...………………..……………………………………………………..0.60 50%
Lawns and Landscaping
Sandy Soil
Flat <2% ………………………………………………………………………………………………………………0.10 0%
Average 2% to 7% …………………………………………………………………………………………………..0.15 0%
Steep >7% ……………………………………………………………………………………………………………0.20 0%
Clayey Soil
Flat <2% ………………………………………………………………………………………………………………0.20 0%
Average 2% to 7% …………………………………………………………………………………………………..0.25 0%
Steep >7% ……………………………………………………………………………………………………………0.35 0%2-year Cf = 1.00 10-year Cf = 1.00100-year Cf = 1.25
Runoff Coefficients are taken from the Fort Collins Stormwater Criteria Manual, Table RO-11
Basin ID Basin Area
(s.f.)
Area of
Concrete
(sq ft)
Area of
Gravel
(sq ft)
Area of
Roofs
(sq ft)
Area of
Single Family
(sq ft)
Soil Type and
Average Slope
Area of
Lawns and
Landscaping
(sq ft)
2-year
Composite
Runoff
Coefficient
10-year
Composite
Runoff
Coefficient
100-year
Composite
Runoff
Coefficient
Composite
% Imperv.
Imperv.
Area (sqft)
Existing Site 5960 105 325 970 0 Clayey | Flat <2%4560 0.35 0.35 0.44 18%1097.50
Proposed Site 5960 430 240 1080 0 Clayey | Flat <2%4210 0.40 0.40 0.50 24%1455.00
Difference (sf imperviousness)357.50
COMPOSITE % IMPERVIOUSNESS AND RUNOFF COEFFICIENT CALCULATIONS
August 15, 2018
Composite Runoff Coefficient with Adjustment
8/15/2018 10:00 AM D:\Projects\1518-001\Drainage\Hydrology\1518-001_Proposed_Rational_Calcs_Single-Family.xlsx\Composite Runoff Coefficient
N89°48'00"E 120.00'
S0
0
°
1
2
'
0
0
"
E
5
0
.
0
0
'
S89°48'00"W 120.00'
N0
0
°
1
2
'
0
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"
W
5
0
.
0
0
'
(37.22
)
(39
.
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)
(39
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7
)
38.5
(37
.
3
9
)
Mc
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30
.
0
'
36.0'
30
.
0
'
36.0'
10.0'
10.0'
54.0'30.0'
38.9
38.5
37.8
37.
8
HP
(38.3)
38.2
(38
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)
(39
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)
(38
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)
(38
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(38.
4
)38.3
EX. MOUNTABLE
CURB
EX. 2.7' WALK
RECLAMATION VILLAGE
DATE: 5/9/18BG:DRAWN BY: LMS
DATEBYREVISIONNo.
PROJECT #: 1518-001
NOTES:
1. BUILDING IMPROVEMENTS SHOWN ON THIS PLOT PLAN ARE CONCEPTUAL FOR THE SOLE PURPOSE OF OBTAINING A BUILDING PERMIT. REFER TO
APPROVED ARCHITECTURAL PLANS FOR CONSTRUCTION OF BUILDING IMPROVEMENTS.
2. ELEVATIONS AND CONTOURS ARE AS SHOWN ON THE ORIGINAL CITY APPROVED GRADING PLAN. DUE TO CIRCUMSTANCES WHICH ARISE SUBSEQUENT
TO THE PREPARATION OF THIS SITE PLAN, CONTRACTOR IS ADVISED THAT ELEVATIONS SHOWN HEREON SHOULD BE VERIFIED PRIOR TO CONSTRUCTION.
3. ALL DRAINAGE ARROWS AND PERCENTAGES ARE SHOWN WITHIN DRAINAGE EASEMENTS AND ARE SHOWN FOR CLARITY PURPOSES AND ARE DESIGNED
TO HAVE CENTERLINE OF DRAINAGE SWALES INLINE WITH PROPERTY LINE, UNLESS OTHERWISE NOTED.
MODEL: BASEMENT: NO GARAGE: NO
CITY: FORT COLLINS COUNTY: LARIMER LOT TYPE:
MINIMUM SETBACKS:Front= 20' Side= 5' Rear= 5'
AP GENERAL CONTRACTING
1" = 20'
0
LEGAL DESCRIPTION: LOT 20, RECLAMATION VILLAGE,
ADDRESS: 237 McKINLEY STREET
PLOT PLAN
FOR
E N G I N E E R N GI
EHTRON R N
PHONE: 970.221.4158
www.northernengineering.com
301 North Howes Street, Suite 100
Fort Collins, Colorado 80521
FG = FINISHED GRADE
TF = TOP OF FOUNDATION
FF = FINISHED FLOOR
TOW = TOP OF WALL
FOG = FRONT OF GARAGE
BOG = BACK OF GARAGE
202010X
FG = 39.5
TF = 40.2
08.15..18ROBADD CONCRETE PATIO (REAR)1
XXXX
X X X X
N89°48'00"E 120.00'
S0
0
°
1
2
'
0
0
"
E
5
0
.
0
0
'
S89°48'00"W 120.00'
N0
0
°
1
2
'
0
0
"
W
5
0
.
0
0
'
1 Story Wood &
Vinyl w/Crawlspace
32.0'
28
.
0
'
36.5'
16
.
5
'
4.5'
11
.
5
'
FF=39.56
MOE=38.50
CHAIN LINK
FENCE
WOOD FENCE
38.
0
37.
2
2
39.
5
39.
7
37.
3
5
37.3
3
38.
2
38.
3
38.1
37.
9
38.
3
38.
2
38.
4
38.
2
37.
3
9
Mc
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LEGAL DESCRIPTION: LOT 20, RECLAMATION VILLAGE,
CITY OF FORT COLLINS, COUNTY OF LARIMER, STATE OF COLORADO,
ADDRESS: 237 NORTH McKINLEY STREET
PRECONSTRUCTION SURVEY
for AP GENERAL CONTRACTING
-FINISHED FLOOR SPOT ELEVATIONS
No.REVISION BY DATE
DATE: 04/27/18DRAWN BY: MAKPROJECT #: 1518-001.03
SCALE 1" = 20'
LEGEND:
THE ATTACHED DRAWING SHOWS THE ELEVATIONS AND DRAINAGE PATTERNS THAT ARE THE REGISTERED LAND SURVEYORS
CERTIFIED FINDINGS OF THE FINISHED GROUND GRADES FOR THE ABOVE DESCRIBED PROPERTY ON THE DATE PROVIDED
ABOVE. THE ELEVATIONS AS DEPICTED HEREON MAY CHANGE SUBSEQUENT TO THE DATE OF THE SURVEY DUE TO NATURAL
AND/OR ARTIFICIAL ACTIONS.
COLORADO P.L.S. NO. 38316
MATT E. LOCKWOOD, PROFESSIONAL LAND SURVEYOR DATE
_____________________________________ ________________
-MINIMIUM OPENING SPOT ELEVATIONS
INFORMATION RECORDED ON: APRIL 23, 2018
-TOP OF FOUNDATION:
-FINISHED FLOOR: 39.56 -GARAGE:
-MOE: 38.50
NOTICE: ALL BEARINGS, DISTANCES, AND
EASEMENTS ARE PER THE SUBDIVISION PLAT
UNLESS OTHERWISE NOTED
E N G I N E E R N GI
EHTRON R N
AP GENERAL CONTRACTING
PHONE: 970.221.4158
www.northernengineering.com
FORT COLLINS: 301 North Howes Street, Suite 100, 80521
GREELEY: 820 8th Street, 80631