HomeMy WebLinkAboutGATEWAY AT HARMONY ROAD PUD, 2ND FILING - FINAL - 1-88D - REPORTS - RECOMMENDATION/REPORT W/ATTACHMENTSITEM NO. 16
PLANNING AND ZONING BOARD MEETING OF yarc:h 77, icm
STAFF REPORT
PROJECT: Gateway at Harmony Road P.U.D., Filing Two - Final, #1-88D
APPLICANT: Paul Heffron
c/o Gefroh/Hattman Inc.
145 W. Swallow Road
Fort Collins, CO. 80525
OWNER: Paul Heffron
1221 Pearl Street
Boulder, CO. 80302
PROJECT PLANNER: Joe Frank
PROJECT DESCRIPTION: A request for final PUD and subdivision plat
approval for a fast food restaurant with drive-thru window (McDonalds) on
1.64 acres, located on the northwest corner of the intersection of Harmony
Road and College Avenue, zoned HB, Highway Business District.
RECOMMENDATION: Approval.
EXECUTIVE SUMMARY: On February 27, 1989, the Planning and Zoning
Board approved the preliminary PUD with certain conditions. The final PUD
plan is in substantial compliance with the approved preliminary plan and
satisfies the conditions for approval.
DEVELOPMENT 300 LaPorte Ave. • P.O. Box 580 • Fort Collins, Colorado 80522 • (303) 221.6750
SERVICES, PLANNING DEPARTMENT
Gateway at Harmony Road PUD, Filing Two - Final - #1-88D
March 27, 1989 P&Z Meeting
Page 2
COMMENTS:
1. Background:
The surrounding zoning and land uses are as follows:
N: HB; undeveloped (proposed restaurant uses in the rest of the Gateway at
Harmony Road P.U.D.)
S: HB; undeveloped (proposed retail/office uses in the Arbor Plaza P.U.D.)
E: HB; existing gasoline service station
W: HB; Wickes Lumber
On February 27, 1989, the Planning and Zoning Board approved the
preliminary P.U.D. plan of the Gateway at Harmony Road with certain
conditions (see below).
2. Land Use
The proposed land use consists of a 5,000 sq. ft. fast food restaurant with
drive-thru window. The land use is consistent with the approved preliminary
plan.
3. Design
Generous landscape setbacks are provided along College Avenue, Harmony Road
and Mason Street frontages. Setbacks range in width between 17 and 50 feet.
Street trees, 3 foot high landscape berms, and shrubbery combine to provide
low level buffering and visual variety along the public streets. Landscaped
parking islands have been provided interior to the site. Approximately 37% of
the entire site is in landscaped area.
The exterior materials of the fast-food
restaurant will match
other buildings on
the site.
The building will be gray
and charcoal toned
brick with colored
aluminum
door and window frames.
Glass will be clear
or tinted bronze.
Roofs will
be pitched and flat. The
roof material will be
dark gray shingles.
The trash
enclosures and ground mounted signs will also utilize
gray brick.
The roof will include lighted beams that have been limited to a single lamp
design which is 1 /2 the intensity of typical McDonald restaurants elsewhere.
4 Conditions for Approval:
At their February 27, 1989 meeting, the Planning and Zoning Board approved
the preliminary plan of the Gateway at Harmony Road P.U.D. with certain
conditions. Attached is a memorandum from the applicants responding to each
of these concerns. The conditions for approval are as follows:
Gateway at Harmony Road PUD, Filing Two - Final - #1-88D
March 27, 1989 P&Z Meeting
Page 3
a That the signage be more in compliance with the level of signage that was
approved on the proiects in the vicinity of Shields Street and Drake Road.
Staff Response: This condition applied to the gasoline service
station (Filing 1). All signs are in compliance with City code.
b That the applicants provide more information on the impact of storm water
quality and volume of storm water that will be released into Mail Creek.
Staff Response: The applicants have responded with more
information on the water quality and volume impacts on Mail Creek.
Also attached is a copy of the final drainage report. The proposed
storm water design is in compliance with City Codes and
requirements.
c That the access language as recommended by the Assistant City Attorney be
a condition for approval regarding required State and City approval of medians
in College Avenue and the right turn -in -only access point.
Staff response: The following wording has been noted on the
final site plan and is legally sufficient to address the concerns of
the Board and Staff regarding the South College Avenue Access
Plan, installation of medians in College Avenue, and the approval of
the right turn -in -only access point:
"If prior to the request for the first building permit, a South
College Avenue Access Plan is established by the City and the State
that includes the installation of raised medians then the developer
shall install all raised medians as shown on this P.U.D. plan and
shall obtain the State's approval of the median installation and
accesses as shown on this P.U.D. plan. The P.U.D. plans shall
address to the satisfaction of the State and City all street and
traffic requirements which are necessary to off -set the impacts of
the proposal. If, however, prior to the request for issuance of the
first building permit, no South College Avenue Access Plan is agreed
upon by the City and the State or a Plan is agreed upon that does
not include the installation of raised medians, then, this P.U.D. plan
is approved on condition that the developer obtain the approval of
the State Highway Department including but not limited to the
proposed right turn -in -only access point and meets the requirements
of the State and City regarding street and traffic improvements
which are necessary to off -set the impacts of the proposal."
d That the applicants provide more information and iustificat-ion of the roof
lighting of the McDonald's restaurant And that the applicants provide
additional information on the intensity of lighting and downward orientation
of lighting of the gas station.
Staff response: The applicants have responded with additional
information and justification of the lighting of the project.
Gateway at Harmony Road PUD, Filing Two - Final - #1-88D
March 27, 1989 P&Z Meeting
Page 4
RECOMMENDATION:
The final plan is in substantial compliance with the approved preliminary
plans. The conditions for approval have been satisfied. All applicable criteria
of the Land Development Guidance System have been met. Therefore, staff
recommends approval of the final P.U.D. plan and subdivision plat of the
Gateway at Harmony Road P.U.D., Filing Two.
:1 2 :
Planning Owner
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LANDSCAPE PLAN °�'""Vol
ELEVATIONS
9
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FINAL DRAINAGE REPORT
THE GATEWAY TO HARMONY ROAD P.U.D.
PREPARED BY
STEWART & ASSOCIATES, INC.
FEBRUARY 8, 1989
0 •
FINAL DRAINAGE REPORT
THE GATEWAY TO HARMONY ROAD P.U.D.
SITE LOCATION: The site, originally known as Harmony P.U.D., is now
The Gateway at Harmony Road, P.U.D. The site is located at the Northwest
corner of the intersection of South College Avenue and West Harmony Road.
The site is bordered on the North by Kensington Drive, on the South by
Harmony Road, on the West by South Mason Street, and on the East by South
College Avenue. It is situate in the Southeast oof Section 35, Township
7 North, Range 69 West of the Sixth P.M., City of Fort Collins, County
of Larimer, State of Colorado.
EXISTING CONDITIONS: The site has a gross area of 5.45 acres and a net
area of 4.43 acres. Filings I and II of The Gateway at Harmony Road
P.U.D. are 2.6 acres of this total site. All of the streets around the
site have been constructed. Revisions to College Avenue will be required
to allow for a continuous right -turn lane. The existing topography slopes
from Northwest to Southeast at approximately 1.8% grade. There is no
offsite runoff entering the site. The 42" Mason Street Interceptor line
storm drain is located along the East side of this site. At present,
the site is covered with native grasses. There are three large cottonwood
trees along the East side of the site.
DESIGN: It is our proposal to detain the 100 year runoff on site in
the proposed parking areas. There are seven ponding areas with a total
capacity of 41,050 cubic feet. This exceeds the required capacity of
40,900 cubic feet as determined by the mass diagram shown on sheet one
of the calculation sheets. The average depth of the ponds will be 1.3
feet when at capacity. The outlet for the ponds will be into the 42
inch Mason Street Interceptor line. The approved amount of runoff into
this line is 0.5 c.f.s. per acre. The total runoff allowed from this
site is 2.73 c. f. s.
There are to be three points of release into the interceptor
line. The release rates at these points were determined by the size
of the ponds. At manhole 1 the release rate is 0.25 c.f.s.; at manhole
2 the release rate is 1.35 c.f.s.; and at manhole 4 the release rate
is 1.14 c.f.s. Each pond will have a restriction plate placed over the
outlet pipe to control the rate of release. The sizing of the outlet
plates is shown on sheets 3 and 4 of the calculations.
CONSTRUCTED: When this project is constructed as designed, it will meet
the City of Fort Collins Specifications.
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Franklin D. Blake, P.E. & L.S.
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P.U.D.
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NVaE VJ.tIt "�'N'•ceNT2
PLANNING OWNER
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MAR 2 31989
CITY MANAGER
5317 Gail Creek Lane
Ft. Collins, CO 60525
March 20, 1989
Ms. Laurie O'Dell, Chairperson
Planning and Zoning Board
Ft. Collins, CO
Dear Ms. O'Dell:
We write as a follow-up to the February 2-17 meeting of
the board, and in Further reaction to the proposed
development on the NUJ corner of Harmony and S. College.
We are concerned about the accuracy of projections of
traffic increases. For the Mc Donald's project the
statement was made that people only stop there on impulse
when they pass by, so no increase in traffic would occur.
That says people don't go there purposely to eat, and that
doesn't seem credible. In the recent meeting about the
Carpet Exchange we were told that most of the customers
would be decorators and architects, so that there would be
little increase in traffic. But later, when an entrance
only From the north was proposed, we were told that these
people would only be about 20 of the traffic. We don't
know what to believe.
Uery truly yours,
Ruth M. Soar
Robert S. Soar
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Mr. Bob Smith
Storm Water Utility
Ft. Collins, CO
Dear Mr. Smith:
5317 Mail Creek Lane
Ft. Collins, CO BOS25
March 21, 19BS
We Write as a follow-up to the February 27 meeting of the P&Z
board on the proposal for the NW corner of Harmony and S. College.
Since our lot backs on Mail Creek, we are specially concerned
about the degregation of water quality in it. The comments of the
Mc Donald's representative about how grease is handled were
reassuring, but we worry about the parking lot and the filling
station. Cars leak their vital fluids, all of which are serious
pollutants. People, with the best of intentions, do spill
liquids. Even a few drops of oil will make a film over a
considerable area of water. Walk around any parking lot and look
at the puddles of oil and in summer antifreeze, waiting to be
Flushed away by the next rain. Mr. Swopes's (Fairway Estates)
comments about the lack of concern for water quality by the city
were not reassuring. Clearly water quality in Mail Creek has
already been degraded, and the proposed development is certain to
degrade it further.
The present lack of qualitu standards by the city is a major
concern. There was mention of federal standards to be imposed in
the future, but it seems a shame to create problems now which will
be more difficult to deal with later.
We also continue to worry about the quantity of runoff permitted
by the present standards. It seems clear that they have not
protected Fairway Estates. We suspect that this proposed
development will multiply the problem, followed by the Carpet
Exchange as another multiplier, followed by Weberg furniture,
Followed by who knows what other multipliers. If the standard is
too low, and the evidence suggests it is, then each additional
roof and paved area will aggravate downstream problems.
Residents who have lived here longer than we tell us that we
already have significant flooding problems, and that they are `t or
5, not 100 year events. Please, let's not make them worse.
Uery truly yours,
Robert S . Soar v
Ruth M. Soar
CC: Laurie O'Dell
City Council Members
0 •
URBAN RUNOFF QUALITY
IN THE
DENVER REGION
EXECUTIVE SUMMARY
Denver Regional Council of Governments
2480 West 26th Avenue, Suite 200E
Denver, Colorado 80211
Preparation of this document was partially financed by an Areawide Water
Quality Management Planning Grant from the U.S. Environmental Protection
Agency.
EXECUTIVE SUMMARY
Urban runoff is one of a number of sources of water pollution referred to
as nonpoint sources because of their diffuse nature. The Denver Regional
Council of Governments (DRCOG) and the U.S. Environmental Protection
Agency (EPA) noted in the mid-70's that nonpoint sources would need to be
controlled if the clean water goals of the region and nation were to be
obtained. This report presents the conclusions of an intensive effort by
DRCOG, with help from a number of agencies, to understand the character-
istics of urban runoff and potential control measures in the Denver region.
The 1977 DRCOG Clean Water Plan expressed concern about nonpoint source
pollution and suggested that for some pollutants urban runoff exceeded
municipal treatment plants as a source. EPA reached the same conclusion
after receiving areawide plans from many parts of the country. Congress,
in 1978, directed EPA to conduct a National Urban Runoff Program to build
upon pertinent prior work and to provide additional pertinent information
and insights. DRCOG was selected as one of 28 agencies to participate in
this program.
As summarized in this report, DRCOG, with help from the United States
Geological Survey, monitored several small basins in the region to determine
the characteristics of urban runoff. Also, the South Platte River was sam-
pled both during storms and dry periods to estimate the effect of urban
runoff on this major water resource. Based on this information, various
tools for predicting urban runoff characteristics were developed. Finally, a
number of local governments and the Urban Drainage and Flood Control Dis-
trict tested various options for controlling urban runoff quality. The major
findings of these .,various tasks are outlined below.
RUNOFF CHARACTERISTICS
Urban runoff was monitored from nine urban basins representing various
land uses and intensities of development. Runoff was analyzed for 15 con-
stituents of concern along with EPA priority (toxic) pollutants. Concen-
trations of constituents were calculated and compared to concentrations in
secondary wastewater effluent. Concentrations and unit -area loads of con-
stituents were related to land use, basin imperviousness, and hydrologic
parameters to determine if relationships existed between these variables.
Also, a pervious detention basin was studied as a control measure for
reducing runoff pollutant loads.
Average event mean concentrations of total lead and zinc were greater in
rainstorm runoff from all basins than secondary wastewater. Concentrations
of total copper were greater in runoff from two basins. Most forms of the
nutrients monitored, expecially total Kjeldahl nitrogen and total phosphorus,
0 •
had much greater concentrations in wastewater. Only nitrite -nitrate nitro-
gen was found in higher concentrations in runoff from several basins.
Very few EPA priority pollutants were detected in runoff samples. Organic
pollutants found were particularly sparse, and the most commonly occurring
one detected was a pesticide. The most significant non -priority pollutant
found was 2,4-D which is a herbicide. Sources of these pollutants include
domestic herbicide and pesticide usage and possible improper disposal,
though verification of sources was not made.
Pollutant loading per runoff amount was not found to be well related to
basin imperviousness or land use. Vague relationships between event mean
concentrations and imperviousness were noted, but proved statistically
insignificant. Concentrations of pollutants did not vary in a predictable
pattern, or to what was anticipated. It was determined that loading was
primarily a function of the quantity of runoff generated at a site. The
portion of rainfall occurring as runoff was found to be well related to basin
imperviousness. As a result, pollutant loading per rainfall amount was
related to basin imperviousness.
The detention basin analysis concluded that the one basin studied was
effective in reducing loads of certain constituents. It was most effective
for reducing loads of metals, chemical oxygen demand, ammonia and dis-
solved phosphorus. Total suspended solids were not greatly reduced on
the average.
EFFECTS ON THE SOUTH PLATTE
A receiving water assessment was included in the program to denote the
effects of urban runoff on the major waterbody in the region. The South
Platte River is the ultimate receiving water for both wastewater effluent and
urban runoff generated within the Denver metropolitan area. Significant
amounts of sediment, bacteria, nutrients, organic matter and heavy metals
were found to enter the river during storm events compared with dis-
charges from wastewater treatment plants over the same time period.
The investigation of the effect of urban runoff on receiving waters involved
three considerations. These were: 1) comparison of pollutant concentrations
monitored in the South Platte River during storm events with those occur-
ring during ambient streamflow, 2) comparison of the relative amounts of
pollutant loads entering the river from storm runoff with those from munici-
pal wastewater sources, and 3) comparison of pollutant concentrations dur-
ing periods of storm runoff and ambient streamflow with water quality
standards in effect for the study segment of the South Platte River.
Several water quality constituents had mean concentrations greater during
storm runoff than during ambient streamflow. Suspended sediment and
fecal coliform bacteria exhibited much greater concentrations during storm
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events, as did oxygen -demanding substances and heavy metals. Total
metals concentrations for lead, zinc, copper, cadmium, iron and manganese
during storm -runoff periods were greater than mean ambient concentrations
and exceeded established stream standards 100 percent of the time. Effec-
tive control of urban runoff to reduce the concentration of these constitu-
ents would improve the quality of water of the South Platte River.
Concentrations of nitrite, nitrate and un-ionized ammonia did not exceed
stream standards during storm periods and will not pose problems for aquat-
ic life. Monitoring data indicated temperature, pH and dissolved oxygen
limits were never exceeded during either storm or ambient periods. Fecal
coliform bacteria exceeded the standard 31 percent of the time during ambi-
ent streamflow and 100 percent of the during storm periods. Un-ionized
ammonia also exceeded the standard 31 percent of the time during ambient
conditions but, due to the effect of dilution, did not exceed the standard
during storms. The levels of bacteria and un-ionized ammonia occurring
during low -flow conditions should be considered further as to their effect
on maintaining beneficial uses of the river.
A comparison of the relative loading from point sources, baseflow and urban
runoff was necessary to denote the effects of urban runoff on the South
Platte River. Results indicated that municipal wastewater discharges con-
tributed the greatest amount of nitrogen, phosphorus, and organic carbon
to the river on an annual basis. Total suspended solids and lead loading
were shown to be predominantly influenced by contributions from urban
runoff .
The effects of urban runoff on beneficial uses are difficult to quantify.
Effects tend to relate more to the protection of the fishery. Recreational
effects are considered to be minimal since little recreation occurs during
storm events. High concentrations of sediment, bacteria and dissolved
metals in urban runoff should be considered as to their effect on the fish-
ery status of the South Platte River and downstream withdrawals of water
for municipal and agricultural uses.
PREDICTING URBAN RUNOFF CHARACTERISTICS
The relationships described above were developed into models which can be
used to predict urban runoff characteristics and effects on the South Platte
River and its tributaries. Information gathered from these models may be
useful in storm water management plans for a preliminary evaluation of the
effects of urban runoff on water quality.
Relationships between rainfall, runoff, unit -area loading and basin charac-
teristics were developed into a nomograph and figures which can be used to
predict urban runoff quantity and quality from small urban basins with spe-
cified characteristics. The use and limitations of these models are dis-
cussed, along with several practical examples. These models are easy to
3
•
0
use and can provide reasonable estimates of
based upon rainfall and land use. Results
ning-level analysis.
runoff quantity and quality
from them are suitable for plan -
Three methods were presented for predicting receiving water character-
istics: 1) regression equations relating loading to streamflow, Z) an empir-
ical method of extrapolating the small basin models to the larger South
Platte River Basin, and 3) a computer -based water quality model. Results
from the first two methods were compared to measured data and were con-
cluded to be within a reasonable margin of error. The last method
described is the use of Hydrologic Simulation Program - FORTRAN (HSPF)
to predict receiving water characteristics. This effort is currently in the
hydrologic calibration phase. Once completed, this model will be used in
planning efforts.
Both of the first two methods described to predict receiving water charac-
teristics employ regression equations with few variables required. A disad-
vantage of using the equations for relating storm flow to loads is that
information on storm volume in cubic feet is required. A drawback of using
the empirical method of extrapolating small basin models to large basins
such as the South Platte River is that this procedure fails to account for
the numerous factors and processes which determine receiving water loads
going from small sites to large basins.
The final prediction tool developed in the program uses weather radar to
estimate the spatial and temporal distribution of rainfall within the DRURP
study area. Radar intensity information was ground-truthed to a network
of raingages, and curvilinear relationships were derived which were used to
predict rainfall amounts. Another element of the weather radar involved
the identification of preferred thunderstorm tracks in the Denver area.
It was concluded that it is possible to define the spatial and temporal dis-
tribution of rainfall through weather radar. However, much more research
is needed to produce "accurate maps of expected rainfall in the region. It
was also concluded that both north and south preferred thunderstorm
tracks do exist in the study area. Areas beneath these tracks are more
likely to receive intense rainfall from thunderstorms.
It was hoped that the radar information could be used to define urban run-
off control priority areas to provide a method for allocating limited funding
to high intensity areas. While potentially useful, radar mapping needs a
much larger data base before areas of greater rainfall can be determined.
Instead, priority areas were based on other characteristics, especially the
amount of construction activity. A hierarchy of control areas is described
beginning with areas experiencing urbanization and continuing to areas
undergoing redevelopment, areas containing existing detention structures,
areas where new flood control structures are being installed, and areas of
greatest runoff potential as determined by degree of development. It is
expected that water bodies would experience the most benefit if control of
urban runoff followed this sequence.
4
•
MANAGING URBAN RUNOFF
The issue for an area such as the Denver region is whether or not it is
cost-effective to develop an urban runoff quality control program. The
DRURP did conclude that certain pollutants may be present in runoff in
sufficient quantities to exceed stream standards. Therefore, it may be
more cost-effective to control nonpoint sources rather than upgrade waste-
water treatment plants to achieve the same stream standard.
Managing urban runoff can be accomplished by implementing structural and
nonstructural Best Management Practices (BMPs) at the local government
level. During the three-year DRURP, Adams County, the City of Engle-
wood, and the City of Littleton participated in a Model Implementation Pro-
gram, where site -specific control measures were developed, followed by a
program to implement the results. The three local governments focused on
either effect -oriented structural controls or cause -oriented nonstructural
controls.
Detention was found to be an effective structural control for removing pol-
lutants such as total phosphorus, lead, Zinc, and total nitrogen. Costs of
detention range from 5200-S400 per acre of drainage area. Another form of
detention, percolation pits, was investigated by Adams County. These pits
remove pollutants by capturing runoff and filtering it through substrate
soils. Costs of percolation pits are estimated to be $5,600 per impervious
acre for one-half inch of runoff. The City of Englewood found detention
basins followed by infiltration pits to be the most cost-effective control mea-
sure for removing pollutants in runoff in order to protect McLellan Reser-
voir. The cost of this system was estimated to be S1 million, which is less
than the cost of diverting the runoff around the reservoir via a pipeline.
Nonstructural controls such as ordinances and maintenance of existing
drainage facilities can help to control sediment carried in urban runoff.
The City of Littleton investigated these two nonstructural control measures
and determined them to be effective. Maintenance of drainage facilities
would reduce flooding problems and allow for proper conveyance of stormwa-
ter, thus eliminating sediment accumulation and providing better detention.
The cost for a maintenance program would range from S150,000 to $200,000
annually. An erosion control program for the City would cost $5,000 and
$10,000 annually. Such a program would control sediment from construciton
sites, thereby reducing pollutants attached to the sediment.
CONCLUSION AND RECOMMENDATIONS
The three-year DRURP effort has been an attempt to quantify urban runoff
effects on water quality in the Denver area. Much has been learned and
5
areas where additional
of recommendations are
the need for additional
resear:h is needed have
made concerning control
research.
been identified. A number
of the region's runoff and
The study has shown that urban runoff is a significant source of some
water pollutants. The most obvious pollutant is total suspended solids.
This was true regardless of the existence of major land disturbances caus-
ing erosion. Urban runoff was also a significant source of fecal coliform
bacteria, oxygen demanding substances, and metals during storms. In
addition, nutrients from urban runoff are and will be a problem for lakes
and reservoirs.
Non -storm urban runoff was also identified as a source of pollutants. This
was not expected and was determined indirectly in the study analysis.
This should be investigated directly to evaluate the magnitude of this
source of pollution and methods for its control.
The DRURP did evaluate two control measures for urban runoff quality and
found both to provide benefits. Detention basins and percolation pits can
both be effective. With this information and some recommendations on prior-
ities, the following steps should be taken to begin an urban runoff quality
control program:
• existing detention ponds throughout the region, but especially in highly
developed areas, should be modified to improve their performance as
treatment mechanisms;
• urban runoff quality control should be coordinated with urban flooding
control. This may mean expanding the responsibilities of the Urban
Drainage and Flood Control District to include quality as well as quanti-
ty. Such a change may require legislative action. However, examples
of quantity and quality agencies exist in other NURP projects -such as
Salt Lake County, Utah and Bellevue, Washington;
• local governments should pursue implementation of drainage ordinances
that incorporate water quality aspects. This may include detention
design, percolation pits and erosion control;
• a central element of local implementation projects is interdepartmental
coordination between planning, engineering and building departments.
Without such coordination, no drainage improvement program will be
successful; and,
• continued maintenance of drainage facilities is needed to achieve opti-
mum performance. A detention basin will not function when accumulated
sediment is not regularly removed.
The implementation of these actions will not totally control pollution from
urban runoff. It will represent an initial step toward the elimination of a
significant source of pollutants.
0
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This study has not answered every question about urban runoff, and in
some cases, the answers presented have led to new questions. To more ful-
ly understand urban runoff, the following issues should be addressed:
• detention basin characteristics. This study was not able to explore, as
thoroughly as originally anticipated, the ability of detention basins to
remove pollutants. Various types of detention need to be tested such
as wet versus dry ponds. Outlet modifications need to be studied to
determine optimum design. Size requirements and holding times should
be developed into design criteria;
• impact assessment. While the DRURP has demonstrated that urban run-
off causes stream standards to be violated, the actual impact on benefi-
cial uses has not been determined. Do the elevated levels of total
suspended solids and various metals during and after a storm harm
aquatic life? Are recreational and water supply uses impaired because
of storm runoff? Questions such as these need to be dealt with before
major implementation costs are incurred;
• point/nonpoint tradeoffs. The concept of nonpoint source control as a
replacement for advanced waste treatment at a domestic or industrial
plant has only been touched upon in this report. This topic should
continue to receive attention so that it can become a normal element of
facility planning; and
• trickle flows. It became obvious during preparation of this report that
stormwater is not the only source of urban runoff. The daily flows
into the region's streams from urban areas due to lawn watering, car
washing, and other activities in some cases are significant contributors
of pollutants. This may mean that point -source treatment and stormwa-
ter control together may still not achieve water quality goals. This is a
significant, new element of the pollution control equation. More infor-
mation is needed about the quality of this dry -weather trickle flow, the
sources of the pollutants within this flow and any methods for control.
After three years of study and evaluation, the Denver area now has a bet-
ter understanding of urban runoff. While more questions exist, enough is
known to begin controlling the quality of urban runoff. The suggestions
made here for implementation and further study will enable the area to move
one step closer to meeting its water quality goals.
7
M n n
Gn
GEFROH HATTMAN INC.
ARCHITECTS/PLANNERS
CONSTRUCTION MANAGEMENT
135 West Swallow Road
Fort Collins, CO 80525
March 23, 1989 (303) 223-7335
Mr. Joe Frank
City of Fort Collins
Planning & Development
Box 580
Fort Collins, CO 80522
RE: GATEWAY @ HARMONY P.U.D.
FILING TWO
Dear Joe:
The following remarks are in response to the conditions placed on the
final P.U.D. by the Board that were not addressed by your comments.
ITEM ONE: SIGNAGE
A. The ground sign, as detailed in the documents, is in conformance to
the size of sign approved at Raintree or C.A.T. 10.
ITEM TWO: WATER VOLUME AND QUALITY
A. Peak flow rate from the site will not change as flow will be re-
leased at the historic rates as defined in the Mail Creek/Fossil
Creek Basin Study.
B. The duration of the peak flow rate will be extended due to deten-
tion. Detention will be adequate to contain the 100-year storm
volume on site.
C. The quality of the water released from the site is to be controlled
by several means. The water will flow from the surface to catch
basins and underground conduit. The catch basins restrict the flow
into the conduit of objects larger than 12" in diameter. The con-
duit being subterranean prevents foreign objects from flowing into
the basin. Policing of the property by the proprietary on an hour-
ly basis as required by his contract with McDonald's reduces the
possibility of foreign objects flowing into the system. In addi-
tion the Developer has agreed that he will work with the Storm
Drainage Department on a pilot project to control and monitor water
quality that flows from the site. This system will be a chambered
manhole which will collect sediment, greases, and oils and prevent
them from flowing down stream.
ITEM THREE: ACCESS PERMIT REQUIREMENTS
A. The language as stated by the City Attorney regarding access permits,
access plans right -in only and procedures has been added to the site
plan as a part of the development requirements.
0 •
Mr. Joe Frank
GATEWAY @ HARMONY P.U.D. - FILING TWO
March 23, 1989
Page 2
ITEM FOUR: LIGHTING
A. The light beams found on the roof of the McDonald's building are of
a level which is one half the intensity of the lighting intensity of
the beams found on the two current McDonald's locations in town.
This reduction replaces the intensity of these roof elements as a
light source and serves to accent the roof and modulate the linear
appearance of the roof element. The beams break up the visual plans
of the roof and provide visual variation both day and night. As an
architectural feature, these elements provide scale to the horizon-
tal mass of a single -story building.
B. The photometrics of the site lighting, directionality, and light
dispersement have been provided to Staff through the cut sheets re-
lating to the specific light fixtures. In summary the data indi-
cates that four feet behind the post the lighting layer is two foot
candles. At the curb line light from the site will be zero. Light-
ing levels on driveways will be five foot candles. Lighting on
walks and parking areas will be four foot candles. The light heads
are adjustable for fine tuning of the light source.
We hope that this information provides you the information you requested
at the preliminary to further evaluate the project in a positive manner.
Sincerely yours,
W
TTMAN INC./ a m
Vice President
kam