HomeMy WebLinkAboutA003 - Staff Report dated November 14, 2012 4
Item #: 3
Date: 11/14/12
CITY OF AMES
DEPARTMENT OF PLANNING AND HOUSING
REPORT TO THE ZONING BOARD OF ADJUSTMENT
DATE PREPARED: November 9, 2012
MEETING DATE: November 14, 2012
REQUEST FOR A CONDITIONAL USE PERMIT IN THE FLOOD WAY OVERLAY
DISTRICT: To allow excavation in the floodway.
PROPERTY OWNER/APPLICANT: Hickory Park, Inc.
LOCATION: 900 SE 16th Street
ZONING: HOC (Highway Oriented Commercial)
ZONING OVERLAY: FW (Floodway Overlay District)
FEMA FLOOD INSURANCE RATE MAP 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 880 feet by 510 feet. The depth will be about 25 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 excavated soil will be placed to the west of the excavation site to raise the site above
the base flood elevation. A local Flood Plain Development Permit was administratively
approved on March 20, 12 to place fill on the portion of the property within the Floodway
Fringe.
APPLICABLE CODE SUMMARY:
Below are excerpts from 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 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.
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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 the attached 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.
(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.
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(f) 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. 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 105 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 provided copies of the application and request to the Iowa Department of
Transportation for their review. The [DOT has no concerns over the proximity of the
excavation to the US 30 right-of-way.
(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.
(j) The property owner is the responsible party for maintaining the area within and
around the project site.
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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.
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 consideration by 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.
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. A portion of the site lies within 1 ,000 feet of a City of Ames water supply well. The
Ames Municipal Code, Section 29.408(8) prohibits excavation within that area in order to
protect the sources of the City's ground water. The proposed excavation is outside the
1,000 feet area. Staff will recommend as a condition of approval that the portion of this
property that is within 1 ,000 feet of a well head be indicated on the ground by staking
throughout the time of active work on the site.
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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
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 top portion of the bank will be a 3:1
slope. The middle portion of the slope, where the water surface elevation of the permanent
pool will likely be, is a 10:1 slope. The lower portion of the slope is, again, 3:1. Native
grasses will be planted on the site. Willows and cattails will rim the water.
9. The Ames Land Use Policy Plan identifies the area of the Floodway as Agriculture.
The remainder of the site is Highway Oriented Commercial. The proposed excavation is
not inconsistent with these designations. The excavation is consistent with the flood plain
management regulations in that it does not increase base flood elevations or flood
velocities.
10. The area is Floodway and no access is anticipated other than for vegetation and
pond maintenance. Access will be from the adjacent property. The City has no easements
or property for which access is needed.
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 for
excavation in the Floodway Overlay District 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 place stakes or other visible markers along an arc that lies
1 ,000 feet from the City of Ames water supply well prior to any excavation , maintain
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the markers until the excavation is complete, and ensure that no excavation occurs
within that protected area.
2. The Zoning Board of Adjustment may deny this request fora 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 Adjustment
act in accordance with Alternative #1, which is to approve the Conditional Use Permit for
excavation in the Floodway Overlay District based on the staff findings and with the
conditions noted above.
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Floodplain Development Permit No,
Engineering"No-Rise" Certificate
Community Ames County Story — State Iowa
Hickory Park Inc.,David Wheelock, Nov. 1,2G12 Scott Renaud, P.E., Nov. 1, 2012
Applicant Date Engineer Date
PO Box 765,Ames,lowa 50010 414 S, 17th Street.Suite 107,Ames,IA 50010
Address Address
515-232-8940 515-233-0000
Phone Ptkone
WE QATA-
1. Location NW V.-- NW Section 13 Range 24W,. Township 83N
Street Address: 900 5 6th Street
2. Panel(s) no.ofNFIPmap(s)effected 19169CO163S
3,Type of Development- Filling_ Grading Excavation X Min Improvements
Routine Maint Substantial lmp;elv New Cons_t_ Other
4.Description of Development. Excavation from the ftoodway to provide fill on an adjacent
psoeenyz There as,oa fill on the area(if flood-way or c�)nstructi3On of any above Qrmind fezturfe,
5.Name of flooding source affected-, Skunk WyeT
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its vaor aaoavatror�only. There is nor Call in the floodway. There is a regligtble effect of the
excavation on flood olevalioni. Tl4 location of the excavarion.is Setween Y brill qoes'and 1hp
bridnes'backwater as the contralliag factor in detefmimng the flq , The bn4coes
_o4clovation5 IWUC p�,Qlga gaC�t L-n thQ flood elevations than d=s the ex!-UL14;ziJ2 ui 1,�W,IQE(2� wo6t.
I no atzmgaliao :Q21 ills ja loss[UstdaliQu ja 114a Jjftrla�Nnu nrld A_JILAAnfial �n fif-rid
This is to certify that I am a duly qualified engineer licensed to practice in the State of IM8
It is to further certify that the attached technical data supports the fact that the proposed
devetopment descrrbed above will NOT create any increase to the 100-year elevations on said
flooding source above at published cross-sections in the Flood Insurance Study fro the above
community dated February 20,2OD8 and will not create any increase to the I 00-year flood
elevations at unpublished cross-sections in the vicinity of the proposed development,
Signature Ott R6TtaLrd, RE, I- [date
Project Manager,FOX Engineehrqj Associates Iowa License No. -12019
Title License No.
My license expires December 31,2012.