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Home My WebLink AboutTaft Speedway ppt.:.®� �p � CITY OF IOWA CITY EL Taft Speedway Flood Mitigation Study October 23, 2012 City Council Work Session CITY OF IOWA CITY Tonight's Objectives • Outline the decisions that need to be made • Outline the process • Present the findings of the HDR report • Staff Recommendations C�- • Share some feedback we are getting from HUD • Answer questions fZ N� CITY OF IOWA CITY Decision Process Outline YES r Do we proceed with a levee or floodwall project to protect the Idyllwild Neighborhood, Parkview Church, and Foster Road? 100YR +3 r 500YR +3 What level of protection r 1� J ml should be provided? NO Z What construction technique should be used? What construction technique should used? What alternate Elevate Develop a Foster northerly Road route YEEDoestheCity y plan should be t used to protect the peninsula g access? What construction technique should be used? What construction technique should used? be Elevate Develop a Foster northerly Road route _ v _ v � — a m a v °o °o m 3 °o °o m > LL LL O LL LL N V N v1" O M N N 0J v M N N 00 > N y/? J LT > CL .-I V L N 1 t M .-i > N J LT M > fl- N J V) LT �. Q F Q < F a a 3 a a 3 Develop a plan and acquire resources J Mal Individuals need to develop a plan ^r rtI CITY OF IOWA CITY Decision Process Schedule k� • October 23rd Work Session —information and questions • October 23rd Council Meeting — no item on the agenda • November 27th Council Meeting — Public Input — Resolution defining decision -4 faq CITY OF IOWA CITY Taft Speedway Flood Mitigation Study Today's Discussion • Study Process • Public Involvement • Initial Screening • Final Alternative Evaluations • Findings -4 Z `1 `115- �t CITY OF IOWA CITY Study Process • Focus: Determine impacts — positive and negative — of flood mitigation alternatives • Method: Collect public input, develop and analyze alternatives, summarize impacts • Result: More detailed information for the City Council to make decision; compliance with CDBG grant requirements fZ IN"imf I CITY OF IOWA CITY Public Involvement • Three Public Meetings: — Two open- microphone — One open -house • Study Website — Linked to City's website — Clearinghouse of project information — Comment submittal • Active project mailing list of over 640 stakeholders faq CITY OF IOWA CITY fa Public Involvement Public meetings: August 25, 2011 Open Mic 73 51 May 31, 2012 Open House 49 10 June 6, 2012 Open Mic 68 27 L' I�g 1 S�� CITY OF IOWA CITY Public Involvement • Comments: Email 7 3 1 Letter 1 19 Meeting Comment 20 4 8 Form Petition 3 Website 20 3 TOTAL 51 10 27 fa L' f 1 CITY OF IOWA CITY Initial Alternatives Screening Ten Alternatives Identified qW Do- Nothing Coralville Reservoir modification Raise Foster Road Levee CDBG /HMGP Buyouts Floodwall Removal of Burlington Dam Levee /floodwall combination Iowa River conveyance Floodproofing of structures (includes improvements structure raises) ��-�� LL I r CITY OF IOWA CITY Initial Alternatives Screening k� Screenin g Criteria: • 100 -Year Protection Level • 2008 Flood Event Protection • 500 -Year Protection Level • Flood Mitigation • Feasibility • Eligibility for HUD Funding faq CITY OF IOWA CITY I Initial Alternatives Screening M Taft Speedway Flood Mitigation Study— Preliminary Screening 0 fZ stage should a large event «cur; however, Me bereft are not substantial and would cue frequent low level flooding f«tlownstream communities. November 2011 Ten initial alternatives were evaluated r `1 am�'.t CITY OyOIOWA CITY 106YrprOtMbn 200posta Feeirt 600'wlimmetbn prn=Mbn Q c rc e m 5 °- c u $ `°: n t 5 Alternative Alternatve OasctlpNOn = is T.MinL/Politio LFeasibi1RY Preliminary screening Results is G; L 8 sp9a5 g ;za�V Si L Do-Nothing No permanent infrastructure Rmpreetime adequate forazemblyand placement of Alternative does not achieve the project (temporary flood improvements; temporary Awasureas may be an issue. The Emergency Response Ran, objectives, but will be carrietl!«ward as protection measures for access and property Y Y Y Y N N N N N N N N N prepared by vl SConsultants l «., determined that the- donwthini alternative for employeda protection would be employed protection for event larger than the 100 w event is clearly comparison purposes. eededi not feasible with temporary m 2. Raise Faster Road Faster R «tl profile would be flwd grade raise at Foster Rwtl is te[M1nically feasible. Alternative tl«i not achieve the proj «t talked to above SMW MEL Significant utility improvements/modifications would also be objectives, but will be carried forward to (apprmimately elevxion 65 y. 01 to Y Y Y Y Y N N N Y N N N N required in conju«tion with rde lame. evaluate incremental costs of providing maintain access to the peninsula ess to peninsula area w. providing ea and flood mitigation. 3. CDBG /HMGP purchase of structures and Buyout of impacted properties is metrically feasible, Alternative not ea riled forward - Does Buputs property potentially impacted by Y Y Y Y N Y Y Y N Y Y Y N Although condominium association and ownership structure not achieve project objectives. All fundiry SD}ymewnt may complicate buywt process. currently available for buyout has been committed at this time. a. Rem«al/MOtlifica Removal or modification to Use of bascule gates, or similar pled configuration could be Altematiw not carried forward - Does Lion of Burlington Burlington Street Dam to improve used binsreas, discharge during ROOd event, yet provide not achiew project objectives. Street Dam comwya «e of Iowa River flood Y y Y N N N N N N N N elevated water surfaces M Core University of Iowa's water preliminary, modeling results show little flows and lower peak river stages Y N plant intake during lowfiows. Legal/pditicalissuesinalude or rear impact (less than l ft) to water In Me Taft Speedway area utilities within existing dam, dam ownership and surface elevations mar project area with coordination with University of Iowa. remicand of Burlington street cam. 5. Iowa River Increae conveyance of Iowa River Consesome improvements are technically feasible; lowever Alternative not carved forward - latent Conveyance by clearing/eacawting channel significant issues to be addressed potentially include of property acquisition, Infrastructure Improvements improvements and /or removing y Y Y Y P p P P p p P P N environmental impacts, land acquisition, and transportation improvements, and environmental and (channel /bridge improwments) bridge obstructions to lower peak river stages in Me Taft Speedway area during Rood events system Impacts. Cost / Benefit ratio likely to be wry poorr utility impact far outweigh the bereft. 6. Coralville Increase flood storagethrough USAGE Division Commander has authority to modify water Alternative not carried forward - Does Reserwir Ma in& physical modifications, control playa /physical modigefons to COralvflle reservoir. not meet project objectives. The IIHR Modification or changes to .,.VN rules M Level of impacts to Me C«alville project, auMMZed aophied this alternative in 2009. The IIHR provide adequate stooge for the purposes, people, and environment would likely require study determined that dredging Me 500 yr event lengthy environmental Impact statement process. Coralvllle Reservoir would provide limited Y Y Y Y N N N N N N N Alternative would also require an extensive amount of additional footl protection against major N N easements or property acquisition. Raising Conalville Dam b floods similar to 2008. A more aggressive provide additional flood storage is likely not feasible. operation plan would increase available fZ stage should a large event «cur; however, Me bereft are not substantial and would cue frequent low level flooding f«tlownstream communities. November 2011 Ten initial alternatives were evaluated r `1 am�'.t CITY OyOIOWA CITY Initial Alternatives Screening fZ Five were screened for additional study 1 a M ®�VI \ice CITY OF IOWA CITY Initial Alternatives Screening Five Alternatives Not Carried Forward: qW Alternative Reason for Screening CDBG /HMGP Buyouts Does not meet project objectives; funding for buyouts fully committed Removal of Burlington Dam Does not meet project objectives, modeling shows little ( <1 ft) benefit at area of interest Iowa River conveyance improvements Extent of property acquisition, infrastructure impacts, and utility and environmental impacts make alternative too costly Coralville Reservoir modification Does not meet project objectives Floodproofing of structures (includes structure Does not meet project objectives — unlikely to raises) provide protection above 100- yrevent; utility and access impacts remain for all events PC fal CITY OF IOWA CITY Flood Mitigation Alternative Analysis Flood mitigation alternatives from initial screening: • Do- Nothing Alternative • Alternative 2B — Foster Road Raise (500 -Year Plus 1 Foot): Provides access to Peninsula area in the event of high Iowa River elevations; no flood damage mitigation benefits. • Alternative 7 - Levee (100 -Year Plus 3 Feet): Earthen levee providing flood mitigation for Idyllwild Neighborhood and Parkview Church. • Alternative 8 - Flood Wall (500 -Year Plus 3 Feet): Floodwall providing flood mitigation for Idyllwild Neighborhood and Parkview Church; floodwall required for this level of protection because of extensive levee footprint at this design elevation. • Alternative 9A - Levee /Flood Wall (500 -Year Plus 3 Feet): Combination of levee with a floodwall along Taft Speedway where ROW is constrained. • Alternative 913- Levee /Flood Wall (500 -Year Plus 3 Feet with Taft Speedway Raise): Similar to Alternative 9A, with Taft Speedway raised within ROW to shorten required wall height. • Alternative 9C- Levee /Flood Wall (100 -Year Plus 3 Feet): Same as alternative 9A, but 100 -year level of protection. • Alternative 913- Levee /Flood Wall (100 -Year Plus 3 Feet with Taft Speedway Raise): Same as alternative 913, but 100 -year level of protection. fa CITY OF IOWA CITY Do Nothing Alternative f- L'7�� r CITY OF IOWA CITY Alternative 2B CITY OF IOWA CITY Alternative 7 fa 4� �JL CITY OF IOWA CITY Alternative 8 CITY OF IOWA CITY Alternative 9A CITY OF IOWA CITY Alternative 9B LEVEE HEIGHT 0' m FLOOD GATE LEVEE c PROPOSED - HEIGHT 8' STORMWATEN WALL - PUMP STATION HEIGHT -10.5 WALL HEIGHT 7S - - \'- LEVEEC - �— T „ ... i'1 HEIGHT =16' \� �! RAISEDROAD - HEIGHT =3 RAISED ROAD - - 31 li i �� HEIGHT =25 P i STORMWATER DISCHARGE LEGEND A I _ l.A PROPOSED ROADWAY ON LEVEE ALTERNATIVE 9B I' PROPOSED LEVEE/ EMBANKMENT FOOTPRINT LEVEE / FLOOD WALL PROPOSED 500 -YEAR -T FLOOD WALL (TOP OF WALL ELEV. =880.0) (500 -YEAR PLUS 3 FEET PROPOSED V SIDEWALK WITH TAFT SPEEDWAY RAISE) �] -nom CITY OF IOWA CITY Alternative 9C fq �• CITY OF IOWA CITY Alternative 9D •'rl r CITY OF IOWA CITY Impacts Evaluated • Environmental — Hazardous Materials — Socio- economic — Archaeological Review — Wetlands — T &E Species — Land Use — Transportation fZ • Existing Infrastructure • Hydraulics • Aesthetics • Floodplain • Property Acquisition • Value of Property Protected • Residual Risk • Utilities 1NI'-w f I CITY OF IOWA CITY Approximate Cost Opinions 1r- Z�l Removals & $0.5 $0.9 $0.9 $1.0 $1.2 $0.9 $1.0 Misc Million Million Million Million Million Million Million Pavement & $1.6 $1.6 $1.0 $1.4 $1.7 $1.3 $1.5 Utilities Million Million Million Million Million Million Million Levee/ $0.0 $1.2 $6.7 $5.1 $4.9 $4.1 $4.0 Floodwall Million Million Million Million Million Million Million Storm water $0.0 $2.3 $2.3 $2.3 $2.3 $2.3 $2.3 Pump Station Million Million Million Million Million Million Million $0.2 $0.2 $0.1 $0.2 $0.1 $0.1 $0.1 Easement Million Million Million Million Million Million Million $0.5 $1.4 $2.5 $2.3 $2.3 $2.0 $2.1 Contingency Million Million Million Million Million Million Million $0.2 $0.5 $0.8 $0.8 $0.8 $0.7 $0.7 Engineering Million Million Million Million Million Million Million $3.0 $8.1 $14.3 $13.1 $13.3 $11.4 $11.7 TOTAL Million Million Million Million Million Million Million 1 al CDBG grant contribution from previously approved project application is $8,011,800. CITY IOWA CITY Findings • Each screened alternative is tech nicallyfeasible. • Potential for impacts on T &E species and wetlands, although it is anticipated that impacts could IV minimized during design. • Multiple utility impacts with each proposed alternative, including overhead electric, water mains, sanitary sewer, and storm sewer. • Multiple infrastructure impacts with each proposed alternative, including neighborhood or property access points, sidewalk and trail, and roadway. • Alternative 2B would provide access to the Peninsula Area during 0.2% annual chance storm events. • Alternatives 7, 8 and 9A through 9D would provide flood mitigation for approximately 24 structures, approximately $498,250 in assessed land value, approximately 92 condominium units currently assessed at approximately $10,491,970, approximately $4,544,320 in total structure value for Parkview Church, and approximately 33.6 acres of land. The City collects approximately $170,000 annually in property tax revenue (2011) from the Idyllwild condominiums. Johnson County Assessor data shows that the 2008 flood event devalued the condominium property values by approximately 25 to 40 percent. • Hydraulic modeling shows proposed alternatives do not negatively impact the hydraulic profile of the Iowa River. • There are aesthetic impacts with each alternative, including obstructed river views and impacted views of residents outside of Idyllwild. • Geotechnical analysis indicates the construction of levees /floodwalls is technically feasible • The POPCCs show that cost of the proposed alternatives ranges from $3 million to $14.3 million. fal CITY OF IOWA CITY Findings — Alternative 2B has the lowest capital cost and maintains access to peninsula area, but provides no flood mitigation for Idyllwild ' residents or Parkview Church. — Alternatives 7, 9C, and 9D all provide flood mitigation for the 1% annual chance storm event. Alternative 7 has the lowest capital costs in addition to the continuous levee section providing the flexibility for temporary measures that could be used to provide mitigation for more extreme flooding events. — Alternative 8 has the highest capital costs for alternatives providing mitigation for the 0.2% annual chance storm event level, but has the least impact on existing infrastructure. — Alternative 9A has the lowest capital cost for projects providing flood mitigation at a 0.2% annual chance storm event level, but has greater impact on existing infrastructure. — Alternatives 9B and 9D illustrate that potential cost savings due to shorter levee /wall heights are offset by the costs required to raise Taft Speedway profile. I faq CITY OF IOWA CITY 100 -Year (+ 3 ft) Levee Condition STA fa Example Cross Section Shown Below is Taken At the Identified Location of Levee: Elevation = 654.0' Transition to Existing Driveway - 125' L' ``11 1 f 1 S`r'll��p; 02t �L T' CITY OF IOWA CITY 'kT,-y Levee /Roadway CITY OF IOWA CITY 500 -Year (+ 3 ft) Floodwall Condition 6D � Top of Floodwall: Elevation = 5600' Example Cross Section Shown Below is Taken At the Identified Location Decision Process Outline YES r Do we proceed with a levee or floodwall project to protect the Idyllwild Neighborhood, Parkview Church, and Foster Road? 100YR +3 r 500YR +3 What level of protection r 1� J ml should be provided? NO Z What construction technique should be used? What construction technique should used? What alternate Elevate Develop a Foster northerly Road route YEEDoestheCity y plan should be t used to protect the peninsula g access? What construction technique should be used? What construction technique should used? be Elevate Develop a Foster northerly Road route _ v _ v � — a m a v °o °o m 3 °o °o m > LL LL O LL LL N V N v1" O M N N 0J v M N N 00 > N y/? J LT > CL .-I V L N 1 t M .-i > N J LT M > fl- N J V) LT �. Q F Q < F a a 3 a a 3 Develop a plan and acquire resources J Mal Individuals need to develop a plan ^r rtI CITY OF IOWA CITY Decision Process Outline YES r Do we proceed with a levee or floodwall project to protect the Idyllwild Neighborhood, Parkview Church, and Foster Road? 100YR +3 r 500YR +3 What level of protection r 1� J ml should be provided? NO Z What construction technique should be used? What construction technique should used? What alternate Elevate Develop a Foster northerly Road route YEEDoestheCity y plan should be t used to protect the peninsula g access? What construction technique should be used? What construction technique should used? be Elevate Develop a Foster northerly Road route _ v _ v � — a m a i LL LL 3 O LL LL v v v v v� v o m v v v m v v ti W > .ti YJ � n .� J L? .� 5 ti J m ( a ti J LT LT �. L? Q F Q < F a a 3 a a 3 Develop a plan and acquire resources J Mal Individuals need to develop a plan ^r rtI CITY OF IOWA CITY Decision Process Outline I5�I r Do we proceed with a levee or floodwall project to protect the Idyllwild Neighborhood, Parkview Church, and Foster Road? 100YR +3 r 500YR +3 What level of protection r 1� J ml should be provided? NO Z What construction technique should be used? What construction technique should used? What alternate Elevate Develop a Foster northerly Road route YEEDoestheCity y plan should be t used to protect the peninsula g access? What construction technique should be used? What construction technique should used? be Elevate Develop a Foster northerly Road route _ v _ v � — a m a v °o °o m 3 °o °o m > LL LL O LL LL N V N v1" O M N N 0J v M N N 00 > N J LT > CL .-I V L N 1 t M .-i > N J LT M > fl- N J V) LT �. Q F Q < F a a 3 a a 3 Develop a plan and acquire resources J Mal Individuals need to develop a plan ^r rtI CITY OF IOWA CITY Decision Process Outline I5�I r Do we proceed with a levee or floodwall project to protect the Idyllwild Neighborhood, Parkview Church, and Foster Road? 100YR +3 r 500YR +3 What level of protection r 1� J ml should be provided? NO Z What construction technique should be used? What construction technique should used? What alternate Elevate Develop a Foster northerly Road route YEEDoestheCity y plan should be t used to protect the peninsula g access? What construction technique should be used? What construction technique should used? be Elevate Develop a Foster northerly Road route _ v _ v � — a m a > LL LL O LL LL N V v N v v v O M N v v v M v v N W > N Y J LT ci > fl- .-I V L N LL 1 t M .-i > N J LT M > fl- N J V) LT �. Q F Q < F a a 3 a a 3 Develop a plan and acquire resources J Mal Individuals need to develop a plan ^r rtI CITY OF IOWA CITY 100 -Year (+ 3 ft) Levee Condition e T aV 3 Top of Levee: Elevation= 654.0' ' Transition to Existing Driveway 20' 54' - 125' SaTMCK Extents of Levee Setback 60' Right -of -Way f_ r _ 4 S CITY OF IOWA CITY 100 -Year (+ 3 ft) Levee Condition 1W rl f_ r CITY OF IOWA CITY i.#*.* . I fal I . I 100 -Year (+ 3 ft) Levee Condition f_ r CITY OF IOWA CITY Decision Process Outline YES r Do we proceed with a levee or floodwall project to protect the Idyllwild Neighborhood, Parkview Church, and Foster Road? 100YR +3 r 500YR +3 What level of protection r 1� J ml should be provided? NO Z What construction technique should be used? What construction technique should used? What alternate Elevate Develop a Foster northerly Road route YEEDoestheCity y plan should be t used to protect the peninsula g access? What construction technique should be used? What construction technique should used? be Elevate Develop a Foster northerly Road route _ v _ v � — a m a v °o °o m 3 °o °o m > LL LL O LL LL N V N v1" O M N N 0J v M N N 00 > N y/? J LT > CL .-I V L N 1 t M .-i > N J LT M > fl- N J V) LT �. Q F Q < F a a 3 a a 3 Develop a plan and acquire resources J Mal Individuals need to develop a plan ^r rtI CITY OF IOWA CITY Decision Process Outline YES r Do we proceed with a levee or floodwall project to protect the Idyllwild Neighborhood, Parkview Church, and Foster Road? 100YR +3 r 500YR +3 What level of protection r 1� J ml should be provided? NO Z What construction technique should be used? What construction technique should used? What alternate Elevate Develop a Foster northerly Road route YEEDoestheCity y plan should be t used to protect the peninsula g access? What construction technique should be used? What construction technique should used? be Elevate Develop a Foster northerly Road route _ v _ v � [a: a m a v ° o ° o m 3 ° o ° o m LL 1" 3 N V N v O M ((VV N M v 00 > > CL J � J LT ( J fl - M N LT Q 0) O F 0) F O a a 3 a a 3 Develop a plan and acquire resources J Mal Individuals need to develop a plan ^r rtI CITY OF IOWA CITY 1"aq w� CITY OF IOWA CITY Decision Process Outline YES r Do we proceed with a levee or floodwall project to protect the Idyllwild Neighborhood, Parkview Church, and Foster Road? 100YR +3 r 500YR +3 What level of protection r 1� J ml should be provided? NO Z What construction technique should be used? What construction technique should used? What alternate Elevate Develop a Foster northerly Road route YEEDoestheCity y plan should be t used to protect the peninsula g access? What construction technique should be used? What construction technique should used? be Elevate Develop a Foster northerly Road route _ v _ v � [a: a m a v ° o ° o m 3 ° o ° o m LL 1" 3 N V N v O M ((VV N M v 00 > > CL J � J LT ( J fl - M N LT Q 0) O F 0) F O a a 3 a a 3 Develop a plan and acquire resources J Mal Individuals need to develop a plan ^r rtI CITY OF IOWA CITY f_ L 4' ^r s1 `r "I im.I� a M ®'•1 \ice CITY OF IOWA CITY Decision Process Outline YES r Do we proceed with a levee or floodwall project to protect the Idyllwild Neighborhood, Parkview Church, and Foster Road? 100YR +3 r 500YR +3 What level of protection r 1� J ml should be provided? NO Z What construction technique should be used? What construction technique should used? What alternate Elevate Develop a Foster northerly Road route YEEDoestheCity y plan should be t used to protect the peninsula g access? What construction technique should be used? What construction technique should used? be Elevate Develop a Foster northerly Road route m — v m .'2 m _ v m .- � [a: a a m v ° o ° o m 3 ° o ° o m LL 1" 3 N V N N v N O M ((VV N M v 00 > LT > CL J � J LT ( J fl - M N LT Q 0) O F 0) F O a a 3 a a 3 Develop a plan and acquire resources J Mal Individuals need to develop a plan ^r rtI CITY OF IOWA CITY Decision Process Outline YES r Do we proceed with a levee or floodwall project to protect the Idyllwild Neighborhood, Parkview Church, and Foster Road? 100YR +3 r 500YR +3 What level of protection r 1� J ml should be provided? NO Z What construction technique should be used? What construction technique should used? What alternate Elevate Develop a Foster northerly Road route YEEDoestheCity y plan should be t used to protect the peninsula g access? What construction technique should be used? What construction technique should used? be Elevate Develop a Foster northerly Road route m — v m .'2 m _ v m .- � — a m a v °o °o m 3 °o °o m > LL LL O LL LL N V N v1" O M N N 0J v M N N 00 > N y/? J LT > CL .-I V L N 1 t M .-i > N J LT M > fl- N J V) LT �. Q F Q < F a a 3 a a 3 Develop a plan and acquire resources J Mal Individuals need to develop a plan ^r rtI CITY OF IOWA CITY HUD Update V� l A 1 at Iowa City keeps HUD officials updated on our'^ progress with this study. There seems to be an indication they may question whether or not the TS project would meet the urgent need criteria. faq CITY OF IOWA CITY HUD Update What this means: All CDBG activities have to meet one of 3 national objectives: • Benefit to Low to Moderate Income Persons (LMI) • Aid in the prevention or elimination of slums or blight • Meet a need having a particular urgency- in our case a national disaster fZ CITY OF IOWA CITY HUD Update Criteria for the Urgent Need national objective • Pose a serious and immediate threat to the health or welfare of the community • Is of recent origin or recently became urgent • Recipient is unable to finance the activity on its own and other sources of funding not available faq CITY OF IOWA CITY HUD Update If a project's Urgent Need criteria is reviewed and no longer applies • Depending on the project, it might meet one of the other national objectives • The TS Project would not qualify under another objective • The funds would need to be returned to the state. faq CITY OF IOWA CITY HUD Update If funds returned to the state: • Formal request letter sent to state asking to change to a LMI eligible project • Good probability (but not a guarantee) that the funds could be used for other Iowa • City LMI Infrastructure projects fZ IM"imf I CITY OF IOWA CITY Questions ? fl -11-4 CITY OF IOWA CITY