HomeMy WebLinkAboutA8 ITEM #: 2
DATE: 03-14-12
CITY OF AMES
DEPARTMENT OF PLANNING AND HOUSING
REPORT TO THE ZONING BOARD OF ADJUSTMENT
DATE PREPARED: March 9, 2012
MEETING DATE: March 14, 2012
REQUEST FOR A CONDITIONAL USE PERMIT IN THE FLOOD WAY OVERLAY
DISTRICT: To allow excavation in the floodway.
PROPERTY OWNER/APPLICANT: Pyle Land LLC, Dennis Pyle
LOCATION: 1400 SE 16th Street and 1500 SE 16th Street
ZONING: HOC (Highway Oriented Commercial); O-GSE (Southeast Gateway Overlay);A
(Agriculture)
ZONING OVERLAY: FW Floodway Overlay District
FEMA F.I.R.M. DESIGNATION: Floodway
PROJECT DESCRIPTION:
The applicant proposes to remove soil within the floodway and redeposit it adjacent to (but
not in) the floodway in order to develop a commercial site. The excavation will be irregular
in shape, approximately 860 feet by 430 feet. The depth will be about 20 feet. It is
anticipated that there will be a permanent pool which will rise and fall, influenced by the
ground water of the Skunk River.
The edge of the excavation will be about 130 feet from the east bank of the Skunk River
and 15 feet from the edge of the easement over the City's 30-inch raw water line which lies
on the east side of the Skunk River. The applicant will provide an easement between the
excavation and the development site for City access to the water main easement. This is in
addition to the existing easement that lies along the south side of SE 16th Street.
The excavated soil will be placed to the east of the excavation site. It will raise the site
about 11 feet above natural grade. The soil that is stockpiled currently on the site will be
regraded and reduced in height. Although the fill site is outside the floodway and floodway
fringe as determined by the February 20, 2008 FEMA study, the previous maps placed this
site within the floodway fringe. Staff reviewed the plan and the maps with the Iowa
Department of Natural Resources, which stated that this likely is a mapping error caused
when the previous paper maps were scanned and digitized for the Digital Flood Insurance
Rate Maps in 2008. If the site were indicated as being within the floodway fringe,
development could occur only if the building pad was elevated to 3 feet above the base
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flood elevation. The applicant will be raising his development site a minimum of 5 feet
above the base flood elevation.
APPLICABLE CODE SUMMARY:
Below are excerpts of Chapter 9, Flood Plain Zoning Regulations, of the Ames Municipal
Code. These excerpts provide the standards on which the project is to be evaluated
(Section 9.4(3) and Section 9.5(2)), and describe the factors on which the Zoning Board of
Adjustment must consider in rendering a decision (Section 9.7(3)(e)(ii)(a)). Following the
standards and the factors, staff has provided comments based upon an analysis of the
site, the submitted project details, and consultation with appropriate City and State officials.
Conditional Uses Allowed
(2) Conditional Uses. The following uses which involve structures (temporary or
permanent), fill, or storage of materials or equipment may be permitted only upon
issuance of a Conditional Use Permit by the Zoning Board of Adjustment as
provided for in Sec. 9.7. Such uses must also meet the applicable provisions of
the Floodway Overlay District Performance Standards.
(a) Uses or structures accessory to open-space uses.
(b) Circuses, carnivals, and similar transient amusement enterprises.
(c) Drive-in theaters, new and used car lots, roadside stands, signs, and
billboards.
(d) Extraction of sand, gravel, and other materials.
(e) Marinas, boat rentals, docks, piers, wharves.
(f) Utility transmission lines, underground pipelines.
(g) Other uses similar in nature to uses described as permitted uses or
listed conditional uses, which are consistent with the performance
standards of Subsection (3) below and the general spirit and purpose of
this ordinance.
Floodway Performance Standards
Section 9.4(3) describes the performance standards for conditional uses that are allowed
by the Board. Following the code excerpts are staff comments. The applicant's statements
addressing these standards are included in his application.
(3) Performance Standards. All Floodway Overlay District uses allowed as a
Permitted or Conditional Use shall meet the following standards:
(a) No use shall be permitted in the Floodway Overlay District that would
result in any increase in the base flood elevation level. Consideration of
the effects of any development on flood levels shall be based upon the
assumption that an equal degree of development would be allowed for
similarly situated lands. Evidence required will be a hydraulic study
performed by a registered professional engineer for the area of drainage
involved.
(b) All uses within the Floodway Overlay District shall:
(i) Be consistent with the need to minimize flood damage.
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(ii) Use construction methods and practices that will minimize and
resist flood damage.
(iii) Use construction materials and utility equipment that are
resistant to flood damage.
(c) No use shall affect the capacity or conveyance of the channel or
floodway or any tributary to the main stream, drainage ditch, or any other
drainage facility or system.
(d) Structures, buildings and sanitary and utility systems, if permitted, shall
meet the applicable performance standards of the Floodway Fringe
Overlay District and shall be constructed or aligned to present the
minimum possible resistance to flood flows.
(e) Buildings, if permitted, shall have a low flood damage potential and
shall not be for human habitation.
(t) Storage of materials or equipment that are buoyant, flammable,
explosive or injurious to human, animal or plant life is prohibited. Storage
of other material may be allowed if readily removable from the Floodway
Overlay District within the time available after flood warning.
(g) Watercourse alterations or relocations (channel changes and
modifications) must be designed to maintain the flood carrying capacity
within the altered or relocated portion. In addition, such alterations or
relocations must be approved by the Department of Natural Resources.
(h) Any fill allowed in the floodway must be shown to have some public
beneficial purpose and shall be limited to the minimum amount necessary.
(i) Pipeline river or stream crossings shall be buried in the streambed and
banks or otherwise sufficiently protected to prevent rupture due to channel
degradation and meandering or due to the action of flood flows.
6) It shall be the responsibility of adjacent property owners to maintain the
location and carrying capacity of the floodway adjacent to their property.
(a) The applicant has provided an "Engineering `No-Rise' Certificate" by which the
engineer states that because the project is excavation only, it will not result in an increase
in base flood elevations in the floodway. He states that the excavation will, in fact, increase
the flood storage capacity of the floodway. The IDNR is satisfied that the excavation will
have no impact on the base flood elevation of the Skunk River.
(b) There is no construction planned. The site will be excavated and seeded.
(c) The excavation site is about 130 feet from the channel of the river. The excavated
site will have no impact on the river channel during normal water flow. City staff has
reviewed the location of the proposed grading with staff of the Iowa Department of Natural
Resources. The IDNR is satisfied that the excavation will have no impact on the channel of
the Skunk River.
There is a storm water drainage easement to channel storm water from SE 16th Street to
the river. This easement is located along the north edge of the proposed excavation and
will be maintained. Storm water from SE 16th Street will be confined to the existing
drainage channel and will not be directed to this excavation area.
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City staff also provided copies of the application and request to the Iowa Department of
Transportation for their review. The IDOT has no concerns over the proximity of the
excavation to US 30.
(d) There will be no structures.
(e) There will be no buildings.
(f) There will be no storage within the floodway.
(g) No watercourse alterations will occur.
(h) No fill will be introduced on site.
(i) The project does not include any stream crossings. However, there is a water line
adjacent to the excavation site that carries the city's raw water from the well fields south of
US 30. This water line is parallel to and on the east bank of the Skunk River. The water
main lies within a 30-foot easement. The top of the proposed excavation is 15 feet from the
edge of the easement. Water and Pollution Control staff has reviewed the proposed
excavation and are satisfied that the water main is sufficiently protected.
Q) The property owner is the responsible party for maintaining the area within and
around the project site.
Factors Upon Which the Decision Shall be Based
Section 9.7(3)(e)(2)(a)describes the factors that the Board must consider when approving
a Conditional Use Permit.
a. Factors Upon Which the Decision of the Board Shall be Based. In passing
upon requests for Conditional Uses or Variances, the Zoning Board shall
consider all relevant factors specified in other sections of this ordinance and:
1. The danger to life and property due to increased flood heights or
velocities caused by encroachments.
2. The danger that materials may be swept onto other lands or
downstream to the injury of others.
3. The proposed water supply and sanitation systems and the ability of
these systems to prevent disease, contamination and unsanitary
conditions.
4. The susceptibility of the proposed facility and its contents to flood
damage and the effect of such damage on the individual owner.
5. The importance of the services provided by the proposed facility to the
community.
6. The requirements of the facility for a flood plain location.
7. The availability of alternative locations not subject to flooding for the
proposed use.
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8. The compatibility of the proposed use with existing development and
development anticipated in the foreseeable future.
9. The relationship of the proposed use to the comprehensive plan and
flood plain management program for the area.
10. The safety of access to the property in times of flood for ordinary and
emergency vehicles.
11. The expected heights, velocity, duration, rate of rise and sediment
transport of the flood water expected at the site.
12. Such other factors which are relevant to the purpose of this ordinance.
In considering these factors, staff offers the following comments for the consideration of
the Board.
1. There is no anticipated danger to life due to a flood event as the proposed excavation
will not increase base flood elevations. The excavation will increase the storage capacity of
the floodway.
2. There will be no structures or materials stored on-site. There will be nothing that can
be swept downstream in the event of a flood.
3. The site will not have water or sanitary sewer service.
4. It is anticipated that this site will be inundated during a flood event. However, there
would be no structural damage as there are no structures proposed in the floodway.
5. The excavation of the site is to provide fill for an adjacent development site. The site
has already been partially filled from soil from the recent US 30 highway reconstruction.
The applicant wishes to complete the fill with the adjacent soil from the floodway.
6 & 7. The soil for the development need not come from this adjacent floodway site.
However, the applicant owns the land and has provided evidence that the excavation will
not have an impact on the base flood elevation.
8. The excavated site will maintain a permanent pool, although the water elevation will
rise and fall with the level of the Skunk River. The banks of the pond will be gently graded
at a 10:1 slope while the interior of the pool will be a steeper 3:1 slope. Native grasses will
be planted on the site.
9. The Ames Land Use Policy Plan identifies this area as Agriculture and Farmstead
with a Greenways overlay. The proposed excavation is not inconsistent with these
designations. The area between the excavation and the river bank will remain as a riparian
corridor, consistent with the Greenway overlay designation.
The excavation is consistent with the flood plain management regulations in that it does not
increase base flood elevations or flood velocities.
10. Access to the US 30 bridge, the SE 16th Street bridge, and the raw water line will be
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maintained through two access easements across the site. One was established as part of
the water main installation and the other will be established as part of this project. The City
is in receipt of the easement from the owner for this new easement but has refrained from
recording it until after approval of the conditional use permit.
11 . In the event of a flood, the excavation is not anticipated to increase heights or
velocities of flood waters. The permanent seeded areas will likely reduce sedimentation to
a greater extent than the current farming practices do.
CONCLUSION:
Based upon the above analysis of the project which included a reading of the relevant
portions of the Flood Plain Zoning Regulations, consideration of the information supplied
by the applicant, and consultation with relevant City officials, staff concludes that the
proposed development meets all criteria for approving the requested conditional use
permit.
ALTERNATIVES:
1. The Zoning Board of Adjustment may approve the Conditional Use Permit based on
the staff's analysis and conclusions. Staff proposes the following conditions to
accompany this alternative:
a) The applicant obtain a Flood Plain Development Permit prior to excavation
and comply with any conditions imposed therein.
b) The applicant obtain a COSECSO permit prior to excavation.
c) The applicant provide a signed easement in a form suitable for recording to
the City for the new access. This easement needs to be recorded prior to
excavation.
2. The Zoning Board of Adjustment may deny this request for a Conditional Use Permit
if the board's findings are that the standard(s) have not been met, detailing the
specific shortfalls.
3. The Zoning Board of Adjustment may table this request for a Conditional Use
Permit and request additional information from the developer, City staff, or Iowa
Department of Natural Resources, and subsequently render a decision within a
reasonable time period.
STAFF RECOMMENDATION:
The Department of Planning & Housing recommends that the Zoning Board of Adjustments
act in accordance with Alternative #1 , which is to approve the Conditional Use Permit for
development in the General Flood Plain Overlay District based on the staff findings and
with the conditions noted.
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Floodplain Development Permit No.
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COMMENTS,
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This is to certity that I am a duly qualified engineer licensed to practice in the State of lo"Y4 I
It is to further certify that the attached technical data supports the fact that the proposed
development described above will NOT create any increase to the 100-year elevations on said
flooding source above at putlished cross-sections in the Flood Insurance Study fro the above
community dated and will not create any increase to the. 100-year flood
elevations at unpublished cross-sections in the vicinity of the proposed development.
(Seal)
Tilt License No,
12,31,20