HomeMy WebLinkAboutMASON STREET INFRASTRUCTURE PROJECT - FDP230016 - SUBMITTAL DOCUMENTS - ROUND 2 - Variance Request (2)
NORTHERNENGINEERING.COM | 970.221.4158 VARIANCE REQUEST: MASON STREET INFRASTRUCTURE
FORT COLLINS | GREELEY 1 | 2
VARIANCE REQUEST
October 4th, 2023
City of Fort Collins
Development Review
281 N College Ave.
Fort Collins, CO 80524
RE: MASON STREET INFRASTRUCTURE
STREETS VARIANCE REQUEST – SANITARY SEWER VERTICAL CRITERIA
NORTHERN PROJECT #1971-001
City staff:
The following is an official variance request to Section 4.06.B.6 & Section 4.06.G.6 in the Fort Collins Utilities
Water and Wastewater Design Criteria Manual. Section 4.06.B.6 states the minimum slope for a 12” pipe shall be
0.22% and section 4.06.G.6 states manholes shall have a minimum of 0.2 foot drop between incoming and
outgoing invert elevations. General information about the project is presented below and detailed information
about the nature of this request follows.
General Information
The project site is located along N Mason Street in between Hickory Street and Hibdon Court in Fort Collins.
The site is currently vacant with an interim N Mason Street alignment and road section. The proposed
development will include a regional detention pond, 2 lots for future commercial development and the
ultimate N Mason Street alignment.
Variance Description
The criteria in question is Section 4.06.B.6 regarding the minimum slopes of sanitary sewer pipe. The table
states that 12” sanitary sewer shall have a minimum slope of 0.22%. This variance request is to allow the
Mason Street Infrastructure project to reduce the minimum slope of the 12” sanitary sewer to 0.18%.
The other criteria in question is Section 4.06.G.6 regarding the required 0.2 foot drop between incoming
invert elevations and outgoing invert elevations. This variance request is to allow the Mason Street
Infrastructure project to provide no drops in elevation through proposed manholes. The minimum
requested slope will still be proposed through the manholes. See the attached exhibit showing the
locations of the requested modifications.
Justification
This project will construct a new 12” sanitary sewer alignment through N Mason Street and Hibdon Court.
This sanitary sewer alignment has been requested by the City of Fort Collins and will bypass a section of
existing sewer adjacent to N College Ave. Once completed the existing sewer along N College Ave will be
abandoned. Due to the realignment of the sanitary sewer, there is an additional 617-Linear Feet of extra
pipe added in between the two existing connection points. With the added pipe distance, the proposed 12”
sanitary sewer slope does not meet the city wastewater slope design requirements. To mitigate the flat
slopes the request to remove drops within manholes would provide an additional 1-ft that can be used to
increase the overall slope. The requested slope minimum slope of 0.18% is a small 0.04% reduction in slope
from the required 0.22%. These modifications will not be detrimental to the overall function of the sewer
system.
NORTHERNENGINEERING.COM | 970.221.4158 VARIANCE REQUEST: MASON STREET INFRASTRUCTURE
FORT COLLINS | GREELEY 2 | 2
VARIANCE REQUEST
This variance requested in this letter will not be detrimental to public health, safety, or welfare. The
variance will provide the best connection between existing sewer lines and overall improve the sanitary
sewer system through this area. The requested variance will not have an adverse impact on the City’s
capital and maintenance costs, nor are they expected to reduce the design life of the roadway
improvements.
Thank you for your consideration and attention to this request.
If you have any questions, please feel free to contact me directly.
Sincerely,
NORTHERN ENGINEERING SERVICES, INC.
MASON RUEBEL, PE
Project Engineer
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QR INC.
200 HICKORY STREET
FORT COLLINS, CO
GRATITUDE LLC
1303 N. COLLEGE AVENUE
FORT COLLINS, CO
1311 N. COLLEGE LLC
HIBON CT.
FORT COLLINS, CO
WOOD RONALD G/ JENNIFER
L/ WILLARD E
122 HIBDON COURT
FORT COLLINS, CO
THOMPSON PROPERTIES LLC
1319 N. COLLEGE AVENUE
FORT COLLINS, CO
D AND S MOTELS INC
1405 N. COLLEGE AVENUE
FORT COLLINS, CO
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EXISTING WATER MAIN
PROPOSED WATER MAIN
PROPOSED STORM SEWER
LEGEND:
NOTES:
1.THE SIZE, TYPE AND LOCATION OF ALL KNOWN UNDERGROUND UTILITIES ARE
APPROXIMATE WHEN SHOWN ON THESE DRAWINGS. IT SHALL BE THE
RESPONSIBILITY OF THE CONTRACTOR TO VERIFY THE EXISTENCE OF ALL
UNDERGROUND UTILITIES IN THE AREA OF THE WORK. BEFORE COMMENCING NEW
CONSTRUCTION, THE CONTRACTOR SHALL BE RESPONSIBLE FOR LOCATING ALL
UNDERGROUND UTILITIES AND SHALL BE RESPONSIBLE FOR ALL UNKNOWN
UNDERGROUND UTILITIES.
2.ALL SANITARY CONSTRUCTION SHALL BE PER THE CITY OF FORT COLLINS
STANDARDS, LATEST EDITION.
3.MANHOLE RIM ELEVATIONS ARE TO BE ADJUSTED TO 14" BELOW FINISHED GRADE. IF
NECESSARY, CONE SECTIONS SHALL BE ROTATED TO PREVENT LIDS BEING LOCATED
WITHIN VEHICLE OR BICYCLE WHEEL PATHS.
4.UTILITY SERVICES ARE SHOWN IN A SCHEMATIC FASHION ONLY. EXACT LOCATIONS
SHALL BE PER THE REQUIREMENTS OF THE RESPECTIVE UTILITY PROVIDERS, AND
ARE SUBJECT TO CHANGE IN THE FIELD.
5.MAINTAIN 10' HORIZONTAL AND 18" VERTICAL MINIMUM SEPARATION BETWEEN ALL
STORM DRAINS, SANITARY SEWER MAINS, WATER MAINS, AND SERVICES.
6.ALL SANITARY MANHOLES TO BE 4'Ø UNLESS NOTED OTHERWISE.
7.REFER TO THE PLAT FOR LOT AREAS, TRACT SIZES, EASEMENTS, LOT DIMENSIONS,
UTILITY EASEMENTS, OTHER EASEMENTS, AND OTHER SURVEY INFORMATION.
W
EXISTING STORM SEWER
SPROPOSED SEWER SERVICE
EXISTING SANITARY SEWER SS
PROPOSED AREA STORM INLET
PROPOSED CURB & GUTTER
PROPOSED SANITARY SEWER
PROPOSED FIRE HYDRANT
EXISTING FIRE HYDRANT
PROPOSED LOT LINE
PROJECT BOUNDARY
EXISTING RIGHT OF WAY
W
EASEMENT LINE
PROPOSED RIGHT OF WAY
PROPOSED COMBO STORM INLET
PROPOSED TYPE-R STORM INLET
PROPOSED WATER SERVICE
NORTH
CALL 2 BUSINESS DAYS IN ADVANCE BEFORE YOU
DIG, GRADE, OR EXCAVATE FOR THE MARKING OF
UNDERGROUND MEMBER UTILITIES.
CALL UTILITY NOTIFICATION CENTER OF
COLORADO
Know what'sbelow.
before you dig.Call
R
(F
U
T
U
R
E
)
KEYMAP
FOR REFERENCE ONLY
SEE UTILITY PLANS FOR APPROVED
SANITARY SEWER DESIGN