HomeMy WebLinkAboutDrainage Reports - 05/05/2017I
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April 25, 2017
City of Fort Col ' s Approved PI ns
Approved b_
Date: - S/S •z0(7
FINAL DRAINAGE AND
EROSION CONTROL REPORT FOR
JEFFERSON AND LINDEN RESTAURANT
Fort Collins, Colorado
AThis Drainage Report is consciously provided as a PDF.
' Please consider the environment before printing this document In its entirety.
When a hard copy Is absolutely necessary, we recommend double -sided printing.
Prepared for:
Blue Ocean Enterprises
401 W. Mountain Ave.
Fort Collins, CO 805211
Prepared by:
NORTHERN
ENGINEERING
260 South College Avenue, Suite 10
Fat Collins, Colorado 80524
Phone: 970.221.4158 Fas: 970.221.4159
w .noMemenglneedng.mm
Project Number: 838-014
North ernEnnineerina.corn 11 970.221.4159 -
' INORTHERN
ENGINEERING
April 25, 2017
' City of Fort Collins
Stormwater Utility
700 Wood Street
Fort Collins, Colorado 80521
RE: Final Drainage and Erosion Control Report for
JEFFERSON AND LINDEN RESTAURANT
' Dear Staff:
Northern Engineering is pleased to submit this Final Drainage and Erosion Control Report for your
' review. This report accompanies the Final Plan submittal for the proposed Jefferson and Linden
Restaurant Project.
' This report has been prepared in accordance to Fort Collins Stormwater Criteria Manual (FCSCM),
and serves to document the stormwater impacts associated with the proposed project. We
understand that review by the City is to assure general compliance with standardized criteria
contained in the FCSCM.
' If you should have any questions as you review this report, please feel free to contact us.
' Sincerely,
NORTHERN ENGINEERING SERVICES, INC.
Aaron Cvar, PhD, PE
' Senior Project Engineer
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301 N. Howes Street, Suite 100, Fort Collins, CO 80521 I 970.221.4158 I www.northernengineering.com
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■V NORTHERN
ENGINEERING
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TABLE OF CONTENTS
I.
GENERAL LOCATION AND DESCRIPTION................................................................... 1
A.
Location.............................................................................................................................................1
B.
Description of Property .....................................................................................................................2
C.
Floodplain..........................................................................................................................................3
II.
DRAINAGE BASINS AND SUB-BASINS.......................................................................4
A.
Major Basin Description....................................................................................................................4
B.
Sub -Basin Description.......................................................................................................................5
III.
DRAINAGE DESIGN CRITERIA................................................................................... 5
A.
Regulations........................................................................................................................................5
B.
Four Step Process..............................................................................................................................5
C. Development Criteria Reference and Constraints............................................................................6
D. Hydrological Criteria.........................................................................................................................6
E. Hydraulic Criteria..............................................................................................................................6
F. Modifications of Criteria................................................................................................................... 6
IV. DRAINAGE FACILITY DESIGN.................................................................................... 6
A. General Concept...............................................................................................................................6
B. Specific Details..................................................................................................................................7
V. CONCLUSIONS........................................................................................................7
A. Compliance with Standards..............................................................................................................7
B. Drainage Concept..............................................................................................................................8
Id»4zI>114 '11111111
APPENDIX
A.1
APPENDIX
A.2
APPENDIX
B
APPENDIX
C
APPENDIX
D
APPENDIX
E
MAP POCKET:
Drainage Exhibit
- Hydrologic Computations
- Hydraulic Computations
- USDA Soils Information
- LID Design Information
- Master Basin Modeling Summary
- Erosion Control Report
' Final Drainage Report
■V I NORTHERN
ENGINEERING
LIST OF FIGURES:
Figure1 — Aerial Photograph................................................................................................ 2
Figure2— Proposed Site Plan................................................................................................ 3
Figure 3 — Existing Floodplains............................................................................................. 4
MAP POCKET:
Proposed Drainage Exhibit
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Final Drainage Report
■� NORTHERN
ENGINEERINQ
Restau
I. GENERAL LOCATION AND DESCRIPTION
A. Location
1. Vicinity Map
LOCATION NORTH
2. The project site is located in Block 7 of Fort Collins, which is within the northwest
quarter of Section 12, Township 7 North, Range 69 West of the 6"' Principal
Meridian, City of Fort Collins, County of Larimer, State of Colorado.
3. The project site is located just north of the intersection of Linden Street and Jefferson
Street.
4. The project site lies within the Old Town Basin, and would typically detain and
release at the Historic 2-year release rate. However, based on master basin modeling
completed with this report, and newly constructed improvements to storm
infrastructure within Jefferson Street, detention is not required for the site. Please see
further discussion in Section ILA, below. Additionally, the site still must provide
water quality treatment. Water quality treatment methods are described in further
detail below.
5. As this is an infill site, the area surrounding the site is fully developed.
Final Drainage Report
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' NORTHERN
ENGINEERING
Jefferson and Linden Restaurant
6. No offsite flows enter the site.
B. Description of Property
1. The development area is roughly 0.57 net acres.
Figure 1 — Aerial Photograph
2. The subject property is currently a park. Existing ground slopes are mild to moderate
(i.e., 1 - 6±%) through the interior of the property. General topography slopes from
northwest to southeast.
3. According to the United States Department of Agriculture (USDA) Natural Resources
Conservation Service (NRCS) Soil Survey website:
http://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx,
the site consists of Paoli Fine Sandy Loam, which falls into Hydrologic Soil Group A.
4. The proposed project site plan is composed of the development of a restaurant.
Parking for the restaurant will be provided offsite. Associated landscaping, water and
sewer lines, and other improvements will be constructed with the development.
Onsite water quality treatment is proposed and will consist of several features which
are discussed in Section IV, below.
Final Drainage Report 2
NORTHERN
ENGINEERING
Jefferson and Linden Restaurant
Figure 2— Proposed Site Plan
5. There are no known irrigation laterals crossing the site.
6. The proposed land use is a restaurant.
C. Floodplain
1. The project site is not encroached by any FEMA or City designated 100-year
floodplain.
Final Drainage Report 3
NORTHERN
ENGINEERING
Jefferson and Linden Restaurant
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Figure 3 —Area Floodplain Mapping
II. DRAINAGE BASINS AND SUB -BASINS
A. Major Basin Description
FEI.IA High Risk - Floodway
CI FEIdA High Risk- 100 Year
ED FEMA Moderate Risk -100 / 500
The project site lies within the Old Town Basin. In this basin, typical detention
requirements are to detain the difference between the 100-year developed inflow rate
and the historic 2-year release rate. We have been in discussion with City Staff on
the possibility of releasing all developed site drainage undetained into the newly
constructed storm system in Jefferson Street. The site is located within the study area
identified in the "Downtown River District (DTRD) Final Design Report", by Ayres
Associates, dated February 2012. The site lies within several master plan sub -
basins, specifically Basins 110, 111, 206, and 210, as shown in DTRD Plan noted
as "Exhibit B-Future Development Map for DTRD Area" (Provided in Appendix E). As
discussed with City Staff, this project would take portions of Basins 110, 111, and
210, with a sum total of 0.40 acre, and incorporate these portions into Basin 206.
In doing so, we will be routing the project site into the recently completed Downtown
River District "Storm Line B". Thus, we are introducing an additional 0.40 acres of
undetained drainage area into this system. Based on the modeling summary provided
in Appendix E, the site will not be required to detain developed flows. Briefly put, the
modeling we have completed adequately addresses any potential concerns related to
storm line capacity in the recently completed Downtown River District "Storm Line B".
The study shows there is negligible impact due to the proposed minor adjustments to
master plan Basins 110, 111, 206, and 210.
Final Drainage Report
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' ■V NORTHERN
ENGINEERING Jefferson and Linden Restaurant
' B. Sub -Basin Description
' 1. The subject property historically drains overland from northwest to southeast. Runoff
from the majority of the site has historically been collected in the existing storm
systems within Linden Street and Jefferson Street.
1 2. A more detailed description of the project drainage patterns is provided below.
III. DRAINAGE DESIGN CRITERIA
1 A. Regulations
There are no optional provisions outside of the FCSCM proposed with the proposed
' project.
B. Four Step Process
The overall stormwater management strategy employed with the proposed project utilizes
the "Four Step Process" to minimize adverse impacts of urbanization on receiving waters.
The following is a description of how the proposed development has incorporated each
step.
Step 1 — Employ Runoff Reduction Practices
' Several techniques have been utilized with the proposed development to facilitate the
reduction of runoff peaks, volumes, and pollutant loads as the site is developed from the
current use by implementing multiple Low Impact Development (LID) strategies including:
Conserving existing amenities in the site including existing vegetated areas and
mature trees.
r� Providing vegetated landscape islands in the parking lot to reduce the overall
' impervious area and to minimize directly connected impervious areas (MDCIA).
Step 2 — Implement BMPs That Provide a Water Quality Capture Volume (WQCV) with
' Slow Release
The efforts taken in Step 1_will facilitate the reduction of runoff; however, urban
development of this intensity will still generate stormwater runoff that will require
' additional BMPs and water quality. The majority of. stormwater runoff from the site will
ultimately be intercepted and treated using extended detention methods prior to exiting the
site.
Step 3 — Stabilize Drainageways
There are no major drainageways within the subject property. While this step may not
' seem applicable to proposed development, the project indirectly helps achieve stabilized
drainageways nonetheless. By providing water quality treatment, where none previously
existed, sediment with erosion potential is removed from downstream drainageway
' systems. Furthermore, this project will pay one-time stormwater development fees, as
well as ongoing monthly stormwater utility fees, both of which help achieve City-wide
drainageway stability.
Step 4 — Implement Site Specific and Other Source Control BMPs.
The proposed project will improve upon site specific source controls compared to historic
conditions:
Nm The proposed development will provide LID and water quality treatment; thus,
eliminating sources of potential pollution previously left exposed to weathering and
runoff processes.
Final Drainage Report 5
■y NORTHERN
ENGINEERING Jefferson and Linden Restauran'
' C. Development'Criteria Reference and Constraints
' The subject property is surrounded by currently developed properties. Thus, several
constraints have been identified during the course of this analysis that will impact the
proposed drainage system including:
1 Existing elevations along the property lines will generally be maintained.
As previously mentioned, overall drainage patterns of the existing site will be
maintained.
' Elevations of existing downstream facilities that the subject property will release to
will be maintained.
' D. Hydrological Criteria
-1. The City of Fort Collins Rainfall Intensity -Duration -Frequency Curves, as depicted in
Figure RA-16 of the FCSCM, serve as the source for all hydrologic computations
' associated with the proposed development. Tabulated data contained in Table RA-7
has been utilized for Rational Method runoff calculations.
2. The Rational Method has been employed to compute stormwater runoff utilizing
coefficients contained in Tables RO-11 and RO-12 of the FCSCM.
3. Three separate design storms have been utilized to address distinct drainage
' scenarios. A fourth design storm has also been computed for comparison purposes.
The first design storm considered is the 80"' percentile rain event, which has been
employed to design the project's water quality features. The second event analyzed is
the "Minor," or "Initial" Storm, which has a 2-year recurrence interval. The third
event considered is the "Major Storm," which has a 100-year recurrence interval.
The fourth storm computed, for comparison purposes only, is the 10-year event.
' 4. No other assumptions or calculation methods have been used with this development
that are not referenced by current City of Fort Collins criteria.
' E. Hydraulic Criteria
1. As previously noted, the subject property maintains historic drainage patterns.
' 2. All drainage facilities proposed with the project are designed in accordance with
criteria outlined in the FCSCM and/or the Urban Drainage and Flood Control District
(UDFCD) Urban Storm Drainage Criteria Manual.
' 3. As stated above, the proposed project does not propose to modify any natural
drainageways.
' F. Modifications of Criteria
1. The proposed development is not requesting any modifications to criteria at this time.
' IV. DRAINAGE FACILITY DESIGN
A. General Concept
1. The main objectives of the project drainage design are to maintain existing drainage
patterns, and to ensure no adverse impacts to any adjacent properties.
2. Onsite water quality treatment will be provided, and is discussed further below.
3. Drainage patterns anticipated for drainage basins shown in the Drainage Exhibit are
Final Drainage Report 6
■� (NORTHERN
ENGINEERING Jefferson and Linden Restaurai
' described below. Drainage basins have been defined for preliminary design purposes
' and are subject to change at Final design; however, general drainage patterns and
concepts are not expected to be significantly altered.
Basin 1
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Basin 1 consists of landscaped areas, and will generally drain via sheet flow across
the existing sidewalk running along the north side of Jefferson Street in to the adjacent
curb and gutter of Jefferson Street. Water quality for this area will be maintained by
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sheet flow through grass buffer areas. It is noted that this basin has minimal new
impervious area introduced by the new 4-foot wide sidewalk along the north side of
the basin, and runoff from this new sidewalk will traverse 50 to 90 feet of grass buffer
prior to entering Jefferson Street Right of Way. This basin does not have any roof
area. All rooftop area is directed by a roof drain system to the southeast into the
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underground LID treatment chamber system in Basin 2.
Basin 2
Basin 2 will consist of landscaped areas, rooftop, and a decorative concrete patio
area. Storm runoff will be directed primarily via roof piping systems and surface flow
into an underground LID treatment chamber system as shown on the Drainage Exhibit.
Please see further discussion of water quality and LID features in Section IV.B, below.
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Basin 3
Basin 3 consists of a small strip of landscaped area along the north side of the
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proposed building that will sheet flow onto the neighboring railroad right of way.
A full-size copy of the Drainage Exhibit can be found in the Map Pocket at the end of
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this report.
B. Specific Details
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1. The prime LID feature that has been incorporated in the design of the
proposed site consists of an underground LID chamber system. The majority
of the proposed impervious area (mainly rooftop area, and decorative concrete
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patio area) will be conveyed into the proposed underground LID chamber
system located under the decorative concrete patio at the southeast corner of
the site. This chamber system will outfall to the newly improved storm line
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system within Jefferson Street.
2. Current City of Fort Collins code minimums are being met with the current site
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plan as summarized in the LID Design information provided in Appendix C.
3. The drainage features associated with the proposed project are all private
facilities, located on private property, with the the site outfall, which will be a
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storm line tie-in within Jefferson Street Street Right of Way.
' V. CONCLUSIONS
A. Compliance with Standards
' 1. The drainage design proposed with the proposed project complies with the City of Fort
Collins' Stormwater Criteria Manual.
' 2. The drainage design proposed with this project complies with requirements for the Old
Final Drainage Report 7
' ■� NORTHERN
ENGINEERING Jefferson and Linden Restaurant
' Town Basin. As noted in Section ILA, the site will not detain flows based on
' modeling submitted for this project.
3. The drainage plan and stormwater management measures proposed with the
proposed development are compliant with all applicable State and Federal regulations
' governing stormwater discharge.
B. Drainage Concept
' 1. The drainage design proposed with this project will effectively limit any potential
damage associated with its stormwater runoff by providing detention and water
quality mitigation features.
2. The drainage concept for the proposed development is consistent with requirements
for the Old Town Basin.
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' Final Drainage Report 8
WI NORTHERN
ENGINEERING
Jefferson and Linden
References
1. Fort Collins Stormwater Criteria Manual, City of Fort Collins, Colorado, as adopted by Ordinance No.
174, 2011, and referenced in Section 26-500 (c) of the City of Fort Collins Municipal Code.
2. Larimer County Urban Area Street Standards, Adopted January 2, 2001, Repealed and
Reenacted, Effective October 1, 2002, Repealed and Reenacted, Effective April 1, 2007.
3. Soils Resource Report for Larimer County Area, Colorado, Natural Resources Conservation
Service, United States Department of Agriculture.
4. Urban Storm Drainage Criteria Manual, Volumes 1-3, Urban Drainage and Flood Control
District, Wright -McLaughlin Engineers, Denver, Colorado, Revised April 2008.
Final Drainage Report
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1 APPENDIX A.1
1 Hydrologic Computations
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APPENDIX A.2
Hydraulic Computations
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APPENDIX B
USDA Soils Information
USDA United States
A product of the National
Department of
Cooperative Soil Survey,
Agriculture
a joint effort of the United
States Department of
N
RCS
Agriculture and other
Federal agencies, State
Natural
agencies including the
Resources
Agricultural Experiment
Conservation
Stations, and local
Service
participants
C.
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,.I:
Custom Soil Resource
Report for
Larimer County
Area, Colorado
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September 26, 2016
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Preface
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Soil surveys contain information that affects land use planning in survey areas. They
highlight soil limitations that affect various land uses and provide information about
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the properties of the soils in the survey areas. Soil surveys are designed for many
different users, including farmers, ranchers, foresters, agronomists, urban planners,
community officials, engineers, developers, builders, and home buyers. Also,
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conservationists, teachers, students, and specialists in recreation, waste disposal,
and pollution control can use the surveys to help them understand, protect, or enhance
the environment.
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Various land use regulations of Federal, State, and local governments may impose
special restrictions on land use or land treatment. Soil surveys identify soil properties
that are used in making various land use or land treatment decisions. The information
is intended to help the land users identify and reduce the effects of soil limitations on
various land uses. The landowner or user is responsible for identifying and complying
with existing laws and regulations:
Although soil survey information can be used for general farm, local, and wider area
planning, onsite investigation is needed to supplement this information in some cases.
Examples include soil quality assessments (hftp://www.nres.usda.gov/wps/portal/
nres/main/soils/health/) and certain conservation and engineering applications. For
more detailed information, contact your local USDA Service Center (http://
ofriices.sc.egov.usda.gov/locator/app?agency=nres) or your NRCS State Soil
Scientist (http:/twww.nres.usda.govtwps/portal/nres/detail/soils/contactus/?
cid=nres142p2_053951).
Great differences in soil properties can occur within short distances. Some soils are
seasonally wet or subject to flooding. Some are too unstable to be used as a
foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic
tank absorption fields. A high water table makes a soil poorly suited to basements or
underground installations.
The National Cooperative Soil Survey is a joint effort of the United States Department
of Agriculture and other Federal agencies, State agencies including the Agricultural
Experiment Stations, and local agencies. The Natural Resources Conservation
Service (NRCS) has leadership for the Federal part of the National Cooperative Soil
Survey.
Information about soils is updated periodically. Updated information is available
through the NRCS Web Soil Survey, the site for official soil survey information.
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs
and activities on the basis of race, color, national origin, age, disability, and where
applicable, sex, marital status, familial status, parental status, religion, sexual
orientation, genetic information, political beliefs, reprisal, or because all or a part of an
individual's income is derived from any public assistance program. (Not all prohibited
bases apply to all programs.) Persons with disabilities who require alternative means
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for communication of program information (Braille, large print, audiotape, etc.) should
contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a
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complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400
Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272
(voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and
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employer.
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Contents
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Preface....................................................................................................................2
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How Soil Surveys Are Made..................................................................................5
Soil Map..................................................................................................................7
SoilMap................................................................................................................8
Legend..................................................................................................................9
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Map Unit Legend................................................................................................10
MapUnit Descriptions........................................................................................10
Larimer County Area, Colorado......................................................................12
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81—Paoli fine sandy loam, 0 to 1 percent slopes.......................................12
References...................... '...................................................................................... 14
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How Soil Surveys Are Made
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Soil surveys are made to provide information about the soils and miscellaneous areas
in a specific area. They include a description of the soils and miscellaneous areas and
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their location on the landscape and tables that show soil properties and limitations
affecting various uses. Soil scientists observed the steepness, length, and shape of
the slopes; the general pattern of drainage; the kinds of crops and native plants; and
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the kinds of bedrock. They observed and described many soil profiles. A soil profile is
the sequence of natural layers, or horizons, in a soil. The profile extends from the
surface down into the unconsolidated material in which the soil formed or from the
surface down to bedrock. The unconsolidated material is devoid of roots and other
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living organisms and has not been changed by other biological activity.
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Currently, soils are mapped according to the boundaries of major land resource areas
(MLRAs). MLRAs are geographically associated land resource units that share
common characteristics related to physiography, geology, climate, water resources,
soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically
consist of parts of one or more MLRA.
The soils and miscellaneous areas in a survey area occur in an orderly pattern that is
related to the geology, landforms, relief, climate, and natural vegetation of the area.
Each kind of soil and miscellaneous area is associated with a particular kind of
landform or with a segment of the landform. By observing the soils and miscellaneous
areas in the survey area and relating their position to specific segments of the
landform, a soil scientist develops a concept, or model, of how they were formed. Thus,
during mapping, this model enables the soil scientist to predict with a considerable
degree of accuracy the kind of soil or miscellaneous area at a specific location on the
landscape.
Commonly, individual soils on the landscape merge into one another as their
characteristics gradually change. To construct an accurate soil map, however, soil
scientists must determine the boundaries between the soils. They can observe only
a limited number of soil profiles. Nevertheless, these observations, supplemented by
an understanding of the soil -vegetation -landscape relationship, are sufficient to verify
predictions of the kinds of soil in an area and to determine the boundaries.
Soil scientists recorded the characteristics of the soil profiles that they studied. They
noted soil color, texture, size and shape of soil aggregates, kind and amount of rock
fragments, distribution of plant roots, reaction, and other features that enable them to
identify soils. After describing the soils in the survey area and determining their
properties, the soil scientists assigned the soils to taxonomic Gasses (units).
Taxonomic classes are concepts. Each taxonomic class has a set of soil
characteristics with precisely defined limits. The classes are used as a basis for
comparison to classify soils systematically. Soil taxonomy, the system of taxonomic
classification used in the United States, is based mainly on the kind and character of
soil properties and the arrangement of horizons within the profile. After the soil
scientists classified and named the soils in the survey area, they compared the
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Custom Soil Resource Report
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individual soils with similar soils in the same taxonomic class in other areas so that
they could confirm data and assemble additional data based on experience and
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research.
The objective of soil mapping is not to delineate pure map unit components; the
objective is to separate the landscape into landforms or landform segments that have
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similar use and management requirements. Each map unit is defined by a unique
combination of soil components and/or miscellaneous areas in predictable
proportions. Some components may be highly contrasting to the other components of
the map unit. The presence of minor components in a map unit in no way diminishes
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the usefulness or accuracy of the data. The delineation of such landforms and
landform segments on the map provides sufficient information for the development of
resource plans. If intensive use of small areas is planned, onsite investigation is
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needed to define and locate the soils and miscellaneous areas.
Soil scientists make many field observations in the process of producing a soil map.
The frequency of observation is dependent upon several factors, including scale of
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mapping, intensity of mapping, design of map units, complexity of the landscape, and
experience of the soil scientist. Observations are made to test and refine the soil -
landscape model and predictions and to verify the classification of the soils at specific
locations. Once the soil -landscape model is refined, a significantly smaller number of
measurements of individual soil properties are made and recorded. These
measurements may include field measurements, such as those for color, depth to
bedrock, and texture, and laboratory measurements, such as those for content of
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sand, silt, clay, salt, and other components. Properties of each soil typically vary from
one point to another across the landscape.
Observations for map unit components are aggregated to develop ranges of
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characteristics for the components. The aggregated values are presented. Direct
measurements do not exist for every property presented for every map unit
component. Values for some properties are estimated from combinations of other
'
properties.
While a soil survey is in progress, samples of some of the soils in the area generally
are collected for laboratory analyses and for engineering tests. Soil scientists interpret
'
the data from these analyses and tests as well as the field -observed characteristics
and the soil properties to determine the expected behavior of the soils under different
uses. Interpretations for all of the soils are field tested through observation of the soils
'
in different uses and under different levels of management. Some interpretations are
modified to fit local conditions, and some new interpretations are developed to meet
local needs. Data are assembled from other sources, such as research information,
production records, and field experience of specialists. For example, data on crop
'
yields underdefined levels of management are assembled from farm records and from
field or plot experiments on the same kinds of soil.
Predictions about soil behavior are based not only on soil properties but also on such
variables as climate and biological activity. Soil conditions are predictable over long
periods of time, but they are not predictable from year to year. For example, soil
scientists can predict with a fairly high degree of accuracy that a given soil will have
'
a high water table within certain depths in most years, but they cannot predict that a
high water table will always be at a specific level in the soil on a specific date.
' After soil scientists located and identified the significant natural bodies of soil in the
survey area, they drew the boundaries of these bodies on aerial photographs and
identified each as a specific map unit. Aerial photographs show trees, buildings, fields,
' roads, and rivers, all of which help in locating boundaries accurately.
I
1
1
1
Soil Map
1
The soil map section includes the soil map for the defined area of interest, a list of soil
map units on the map and extent of each map unit, and cartographic symbols
1
displayed on the map. Also presented are various metadata about data used to
produce the map, and a description of each soil map unit.
1
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Custom Soil Resource Report
7
I
I
1
1
Map Unit Legend
� -
"�Larimer County Area, Colorado (C0644)
E
MapUnk
Map Unit Name "Aeres''InkA01
Percent,of
Symbol
81
Paoli fine sandy loam, 0 to 1 0.7
100.0%
percent slopes
Totals for Area of Interest
0.7
100.0%
Map Unit Descriptions
The map units delineated on the detailed soil maps in a soil survey represent the soils
or miscellaneous areas in the survey area. The map unit descriptions, along with the
maps, can be used to determine the composition and properties of a unit.
A map unit delineation on a soil map represents an area dominated by one or more
major kinds of soil or miscellaneous areas. A map unit is identified and named
according to the taxonomic classification of the dominant soils. Within a taxonomic
class there are precisely defined limits forthe properties of the soils. On the landscape,
however, the soils are natural phenomena, and they have the characteristic variability
of all natural phenomena. Thus, the range of some observed properties may extend
beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic
class rarely, if ever, can be mapped without including areas of other taxonomic
classes. Consequently, every map unit is made up of the soils or miscellaneous areas
for which it is named and some minor components that belong to taxonomic classes
other than those of the major soils.
Most minor soils have properties similar to those of the dominant soil or soils in the
'
map unit, and thus they do not affect use and management. These are called
noncontrasting, or similar, components. They may or may not be mentioned in a
particular map unit description. Other minor components, however, have properties
and behavioral characteristics divergent enough to affect use or to require different
'
management. These are called contrasting, or dissimilar, components. They generally
are in small areas and could not be mapped separately because of the scale used.
Some small areas of strongly contrasting soils or miscellaneous areas are identified
by a special symbol on the maps. If included in the database for a given area, the
contrasting minor components are identified in the map unit descriptions along with
some characteristics of each. A few areas of minor components may not have been
observed, and consequently they are not mentioned in the descriptions, especially
where the pattern was so complex that it was impractical to make enough observations
to identify all the soils and miscellaneous areas on the landscape.
'
The presence of minor components in a map unit in no way diminishes the usefulness
or accuracy of the data. The objective of mapping is not to delineate pure taxonomic
classes but ratherto separate the landscape into landforms or landform segments that
have similar use and management requirements. The delineation of such segments
'
on the map provides sufficient information for the development of resource plans. If
intensive use of small areas is planned, however, onsite investigation is needed to
define and locate the soils and miscellaneous areas. _
'
10
Custom Soil Resource Report
An identifying symbol precedes the map unit name in the map unit descriptions. Each
description includes general facts about the unit and gives important soil properties
and qualities.
Soils that have profiles that are almost alike make up a soil series. Except for
differences in texture of the surface layer, all the soils of a series have major horizons
that are similar in composition, thickness, and arrangement.
Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity,
degree of erosion, and other characteristics that affect their use. On the basis of such
differences, a soil series is divided into soil phases. Most of the areas shown on the
detailed soil maps are phases of soil series. The name of a soil phase commonly
indicates a feature that affects use or management. For example, Alpha silt loam, 0
to 2 percent slopes, is a phase of the Alpha series.
Some map units are made up of two or more major soils or miscellaneous areas.
These map units are complexes, associations, or undifferentiated groups.
A complex consists of two or more soils or miscellaneous areas in such an intricate
pattern or in such small areas that they cannot be shown separately on the maps. The
pattern and proportion of the soils or miscellaneous areas are somewhat similar in all
areas. Alpha -Beta complex, 0 to 6 percent slopes, is an example.
An association is made up of two or more geographically associated soils or
miscellaneous areas that are shown as one unit on the maps. Because of present or
anticipated uses of the map units in the survey area, it was not considered practical
or necessary to map the soils or miscellaneous areas separately. The pattern and
relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha -
Beta association, 0 to 2 percent slopes, is an example.
An undifferentiated group is made up of two or more soils or miscellaneous areas that
could be mapped individually but are mapped as one unit because similar
interpretations can be made for use and management. The pattern and proportion of
the soils or miscellaneous areas in a mapped area are not uniform. An area can be
made up of only one of the major soils or miscellaneous areas, or it can be made up
of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example.
Some surveys include miscellaneous areas. Such areas have little or no soil material
and support little or no vegetation. Rock outcrop is an example.
11
I
Custom Soil Resource Report
' Larimer County Area, Colorado
81—Paoli fine sandy loam, 0 to 1 percent slopes
'
Map Unit Setting
National map unit symbol: jpxx
Elevation: 4,800 to 5,600 feet
Mean annual precipitation: 13 to 15 inches
'
Mean annual air temperature: 48 to 50 degrees F
Frost -free period. 135 to 150 days
Farmland classification: Prime farmland if irrigated
'
Map Unit Composition
Paoli and similar soils: 85 percent
Minor components: 15 percent
'
Estimates are based on observations, descriptions, and transacts of the mapunit.
Description of Paoli
'
Setting
Landform: Stream terraces
Landform position (three-dimensional): Tread
'
Down -slope shape: Linear
Across=slope shape: Linear
Parent material: Alluvium
'
Typical profile
HI - 0 to 30 inches: fine sandy loam
H2 - 30 to 60 inches: fine sandy loam, sandy loam, loamy sand
H2 - 30 to 60 inches:
'
H2 - 30 to 60 inches:
Properties and qualities
Slope: 0 to 1 percent
'
Depth to restrictive feature: More than 80 inches
Natural drainage class: Well drained
Runoff class: Very low
'
Capacity of the most limiting layer to transmit water (Ksat): High (2.00 to 6.00 in/hr)
Depth to water table: More than 80 inches
Frequency of flooding: None
'
Frequency of ponding: None
Calcium carbonate, maximum in profile: 15 percent
Salinity, maximum in profile: Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm)
'
Available water storage in profile: Very high (about 16.5 inches)
Interpretive groups
Land capability classification (irrigated): 1
Land capability classification (nonirrigated): 3c
'
Hydrologic Soil Group: A
Ecological site: Overflow (R067BY036CO)
Hydric soil rating: No
Minor Components
Caruso
t
Percent of map unit: 6 percent
1
12
Custom Soil Resource Report
'
Hydric soil rating: No
Table mountain
Percent of map unit: 6 percent
Hydric soil rating: No
Fluvaquentic haplustolls
Percent of map unit: 3 percent
Landform: Terraces
'
Hydric soil rating: Yes
13
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
References
American Association of State Highway and Transportation Officials (AASHTO). 2004.
Standard specifications for transportation materials and methods of sampling and
testing. 24th edition.
American Society for Testing and Materials (ASTM). 2005. Standard classification of
soils for engineering purposes. ASTM Standard D2487-00.
Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of
wetlands and deep -water habitats of the United States. U.S. Fish and Wildlife Service
FWS/OBS-79/31.
Federal Register. July 13, 1994, Changes in hydric soils of the United States.
Federal Register. September 18, 2002. Hyddc soils of the United States.
Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils
in the United States.
National Research Council. 1995. Wetlands: Characteristics and boundaries.
Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S.
Department of Agriculture Handbook 18. http:/twww.nres.usda.govtwps/portal/nres/
detail/national/soils/?cid=nres 142p2_054262
Soil Survey Staff.1999. Soil taxonomy: A basic system of soil classification for making
and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service,
U.S. Department of Agriculture Handbook436. http://www.nres.usda.govtwps/portal/
nres/detail/national/soils/?cid=nres 142p2_053577
Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of
Agriculture, Natural Resources Conservation Service. http://www.nres.usda.govtwps/
portal/nres/detail/national/soi Is/?cid=n res 142p2_053580
Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and
Delaware Department of Natural Resources and Environmental Control, Wetlands
Section.
United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of
Engineers wetlands delineation manual. Waterways Experiment Station Technical
Report Y-87-1.
United States Department of Agriculture, Natural Resources Conservation Service.
National forestry manual. http://www.nres.usda.govtwps/portal/nres/detail/soils/
home/?cid=nres 142p2_053374
United States Department of Agriculture, Natural Resources Conservation Service.
National range and pasture handbook. http://www.nres.usda.gov/wps/portal/nres/
detail/national/land use/rangepasture/?cid=stelprdb 1043084
14
Custom Soil Resource Report
'
United States Department of Agriculture, Natural Resources Conservation Service.
National soil survey handbook, title 430-VI. http://www.nrGs.usda.gov/Wps/portal/
'
nres/detail/soils/scientists/?cid=nres142p2_054242
United States Department of Agriculture, Natural Resources Conservation Service.
2006. Land resource regions and major land resource areas of the United States, the
'
Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296.
http://www. nres.usda.govtwps/portal/nres/detail/national/soils/?
cid=nres142p2_053624
United States Department of Agriculture, Soil Conservation Service. 1961. Land
capability classification. U.S. Department of Agriculture Handbook 210. http://
www.nrcs.usda.gov/lntemet/FSE—DOCUMENTS/nrcsl42p2_052290.pdf
1
1
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1
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15
I
' APPENDIX C
' LID Design Information
1
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■� NORTHERN
ENGINEERING
Project Title
Project Number
Client
Basins
Jefferson & Linden Restaurant
838-014
Vaults
WQCV=a 0.9V3 _1.19d2+0
WQCV = Watershed inches of Runoff (inches)
a = Runoff Volume Reduction (constant)
i = Total imperviousness Ratio (i = I,q/100)
0
0.5
0.45
m 0.4
r
c 0.35
u 0.3
r
u 0.25
3 0.2
> 0.15
u
Cr 0.1
3
I4!
0
Date: March 1, 2017
Calcs By: A- Reese
Drain Time 12 hi
a = 0.8
i = 58.00%
WQCV = 0.184 in
Water Quality Capture Volume
WQCV=a O.9k3-1.19f2+0.7&) --�—�.
0 0 0 0 0 0 0 0 0 0
C F+ N W A In T �I Oo iD O
O O C O O O O O O O O
Total Imperviousness Ratio (i = Iwa/100)
Figure EDB-2 - Water Quality Capture Volume (WQCV), 80th Percentile Runoff Event
V _ ( WQCV A A= 1 0.28ac ,
Il
12
V = I 0.0042ac-ftl 184 cu. ft.
V = Water Quality Design Volume (ac-ft)
WQCV = Water Quality Capture Volume (inches)
A = Watershed Area (acres)
I
1
1
1
I
I
I
■� NORTHERN
ENGINEERING
Chamber Volume Calculation I FAA Method
Project: Jefferson & Lindei
Project Location: Fort Collins, Colorado
Calculations By: A. Boesr Date: March 1, 2017
Basin No.: 1
Input Variables
Results
Design Point 1
Design Storm WQ
Developed "C" = 0.88
Area (A)= 0.28 acres
Max Release Rate = 0. - 1 Cfs
Required Storage Volume
Quantity Storage 108 ft3
Time
Time
Ft.Collins
WQ
Intensity
Q2
Inflow
(Runoff)
Volume
Outflow
(Release) Volume
Storage
Detention
Volume
(mins)
(secs)
(in/hr)
(cfs)
(ft)
(ft)
(ft )
5
300
1.43
0.4
105
33
72
10
600
1.11
0.3
163
66
97
15
900
0.94
0.2
207
99
108
20
1200
0.81
0.2
238
132
106
25
1500
0.72
0.2
264
165
99
30
1800
0.65
0.2
288
198
90
35
2100
0.59
0.1
1 303
231
72
40
2400
0.54
0.1
316
264
52
45
2700
0.50
0.1
329
297
32
50
3000
0.46
0.1
340
330
10
55
3300
0.44
0.1
354
363
-9
60
3600
0.41
0.1
364
396
-32
65
3900
0.39
0.1
370
429
-59
70
4200
0.37
0.1
378
462
-84
75
4500
0.35
0.1
383
495
-112
80
4800
0.33
0.1
390
528
-138
85
5100
0.32
0.1
396
561
-165
90
5400
0.31
0.1
406
594
-188
95
5700
0.29
0.1
407
627
-220
100
6000
0.28
1 0.1
1 414
1 660
-246
105
6300
0.27
0.1
419
693
-274
110
6600
0.26
0.1
423
726
-303
115
6900
0.26
0.1
434
759
-325
120
7200
0.25
0.1
435
792
-357
' 1. Release rate governed by flow through geotexile. See StormTech Data and Chamber Summary for additional information.
1
D:IProjectsl838-0141DrainagelLID1838-014 FAA_Chamber.xlsml
' APPENDIX D
' Master Basin Modeling Summary
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' INORTHERN
ENGINEERING
' Modeling Summary Report
' Date: January 11, 2017
Project: Jefferson and Linden Restaurant
' Fort Collins, Colorado
Attn: Mr. Shane Boyle
'
Fort Collins_ Utilities
700 Wood Street
'
Fort Collins, Colorado 80524
' Dear Mr. Boyle: -
This modeling summary report is intended to supplement the PDP and FP Drainage reports for
' the Jefferson and Linden Restaurant project. The proposed development site is located just
northwest of the intersection of Jefferson Street and Lindon Street in Fort Collins, Colorado.
The site is located within the study area identified in the "Downtown River District (DTRD) Final
Design Report", by Ayres Associates, dated February 2012. The site lies within several master
' plan sub -basins, specifically Basins 110,111, 206, and 210, as shown in on the attached "Exhibit
B-Future Development Map for DTRD Area" (Please see Attachment 1). As we have discussed
with you, we would like to take portions of Basins 110,111, and 210, with a sum total of 0.40
' acre, and incorporate these portions into Basin 206. In doing so, we will be routing the
Jefferson and Linden Restaurant project site into the recently completed Downtown River
District "Storm Line B". Thus, we are introducing an additional 0.40 acres of undetained
' drainage area into this system.
Hydrologic modeling was completed in this report utilizing the computer program EPA SWMM
' S. Specifically, the proposed site is located within SWMM Basin 206, and the updated modeling
completed for this study incorporates an additional 0.40 acres as discussed above. We note
' that Basin 206 had an assumed percent impervious value of 90% in the original Ayres model,
and we have not changed this parameter. The proposed site plan will 'not exceed this percent
impervious assumption. Please see the disk provided in Attachment 3 for an electronic copy of
' the modified master plan SWMM Model.
Table 1, below, summarizes changes in Peak 100-year discharge at SWMM Links B6 (site tie-in
' point) through B3 (several links downstream of the site). Table 2, below. summarizes changes
in 100-year HGL at SWMM Manholes MHB6 through B3. Please see Attachment 2 for selected
portions of the Downtown River District "Storm Line B" plan set, and we note that the minor
1
increases in HGL summarized in Table 1, below will not bring HGL above junction rim elevation
at any junction.
'
TABLE 1- Summary of Changes in Peak 100-year Flow
Original Ayres Revised Model Change In
'
Link
Model Peak Peak 100-yr Peak 100-yr
100-yr Flow Flow Flow (CFS)
B3
302.49 304.01 1.52
84
285.26 287.26 2
'
BS
151.59 153.22 1.63
66
109.55 111.64 2.09
TABLE 2 - Summary of Changes in 100-year HGL
Original
Original Revised
Ayres Model
Ayres Model Peak
'
Peak 100-yr
Model 100-yr Revised Manhole
Change
Manhole
100-yr HGL Manhole Model 100- Rim Elev.
100-yr
Node
Depth (FT)
(FT) Depth (FT) yr HGL (FT) (FT) ,
HGL (FT)
M H B2
4.07
4961.39 4.13 4961.45 4965.03
0.06
MH133
SA
4964.02 5.49 4964.11 4968.21
0.09
M H B4
6.02
4964.9 6.09 4964.97 4969.1
0.07
'
MH85
6.26
4966.78 6.39 4966.91 4970.39
0.13
MH86
6.11
4969AS 6.3 4969.64 4974.19
0.19
' In summary, the modeling provided adequately addresses any potential concerns related to
' storm line capacity in the recently completed Downtown River District "Storm Line B". This
study shows there is negligible impact due to the proposed minor adjustments to master plan
Basins 110,111, 206, and 210.
Please feel free to contact me with any questions you may have.
Sincerely
NORTHERN ENGINEERING
' Aaron Cvar, PhD, PE
Senior Project Engineer
2
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Attachment 1
Annotated Exhibit B-Future Development Map for DTRD Area
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' Modified Master Plan SWMM Model (on Disk)
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' APPENDIX E
' Erosion Control Report
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' (NORTHERN
ENGINEERING
' EROSION CONTROL REPORT
' A comprehensive Erosion and Sediment Control Plan (along with associated details) has been
included with the final construction drawings. It should be noted, however, that any such Erosion
and Sediment Control Plan serves only as a general guide to the Contractor. Staging and/or phasing
' of the BMPs depicted, and additional or different BMPs from those included may be necessary
during construction, or as required by the authorities having jurisdiction.
' It shall be the responsibility of the Contractor to ensure erosion control measures are properly
maintained and followed. The Erosion and Sediment Control Plan is intended to be a living
document, constantly adapting to site conditions and needs. The Contractor shall update the
' location of BMPs as they are installed, removed or modified in conjunction with construction
activities. It is imperative to appropriately reflect the current site conditions at all times.
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The Erosion and Sediment Control Plan shall address both temporary measures to be implemented
during construction, as well as permanent erosion control protection. Best Management Practices
from the Volume 3, Chapter 7 — Construction BMPs will be utilized. Measures may include, but are
not limited to, silt fencing along the disturbed perimeter, gutter protection in the adjacent roadways
and inlet protection at existing and proposed storm inlets. Vehicle tracking control pads, spill
containment and clean-up procedures, designated concrete washout areas, dumpsters, and job site
restrooms shall also be provided by the Contractor.
Grading and Erosion Control Notes can be found on the Utility Plans. The Final Plans contain a
full-size Erosion Control sheet as well as a separate sheet dedicated to Erosion Control Details. In
addition to this report and the referenced plan sheets, the Contractor shall be aware of, and adhere
to, the applicable requirements outlined in the Development Agreement for the development. Also,
the Site Contractor for this project will be required to secure a Stormwater Construction General
Permit from the Colorado Department of Public Health and Environment (CDPHE), Water Quality
Control Division — Stormwater Program, prior to any earth disturbance activities. Prior to securing
said permit, the Site Contractor shall develop a comprehensive StormWater Management Plan
(SWMP) pursuant to CDPHE requirements and guidelines. The SWMP will further describe and
document the ongoing activities, inspections, and maintenance of construction BMPs.
Final Erosion control Report
I
' MAP POCKET
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NOTES:
1. REFER TO THE Rinsed.WUWME a EPOegN CplRW liITRr FOR JEREP501+
May UNDENRAUBBI By N ORIHERK EMWEERWG.MMMN By 201T
FOR ES
PROJECT BENCHMARKS
RIOJELT DATUM: Ni BB
BENCHM4RRNY.
Cod FMCdlins BenCllrek B : ort topot otN at IM Ypnel we Nesm
tln NMllweat cane• of Unch $k aMJaBersun St.
Elevation: 4978.05
BENCHNIANI
City of Fort Colima Benchmark 113: Sou01we9 Comer W College Ave. and
Maple $t, on a anorete petlk agree Ease.
Elevation: 497975
Pleev Note: This plan set IB using NAVGB3far a vertical di Surroun itq
Oevalcpmenta Mve used NGVD29 Unadjusted for their venal deWms.
IF NGVD29 Unadjusted datum is happeed or any Wtpst. Me following
WiNdon shwld We Feel
NGVDYB Unadjusted - NRVCBB-3.1B (BM BWj
Ni Unadjusted - Nhi W -3.1T (BM 1-13)
Basis of Bxtima
$mAhMtelly Ilne of Block T. City of Fort Collins Be time Sol 41-BY 33'
West
FOR DRAINAGE REVIEW ONLY
NOT FOR CONSTRUCTION
MLL VNtT NMEM,.IIDN CENaR C(
K abflglo Call
you
111e�rr3w.desq.
City of Fort Coll -
UTILITY PLAN
CHECKED BY:
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Data
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CHECKM BIC
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C600
14 of 16