HDR | Presentation Update to Flood Project Working Group Shawn Gooch, P.E. City of Sparks February 27, 2008 North Truckee Drain Relocation Project

City of Sparks/HDR Engineering, Inc. Final Project Update December 18, 2007 Shawn K. Gooch, P.E.Jay Aldean, P.E. Flood Control ManagerProject Manager City of SparksHDR North Truckee Drain Relocation Project JoAnn Meacham, P.E. Utility Manager City of Sparks

HDR | Presentation What has happened since our last meeting? Corps decided to check/review their hydrology for the North Truckee Drain Changed calculation methods Found inconsistencies with application of original method HDR performed hydrologic update Changed design criteria for the Truckee River Flood Project from the 100-yr to the 117-yr storm Resulted in a significantly larger conveyance structure (from 2: 10’ x 10’ culverts to 2: 22’ x 10’ culverts)

HDR | Presentation Large Box Culvert Photos

HDR | Presentation Alternative Alignments Considered

HDR | Presentation Alignments as Analyzed

HDR | Presentation Alignments Characteristics ALIGNMENT 1 – PURPLE (NDOT – VISTA)  Runs east along Brierley Way to Vista  Located in UPRR R/W (north of tracks) east of Vista  3 Jack & Bore Crossings: Vista, I-80, UPRR  Overall Length: ~ 6,400 LF ALIGNMENT 2 – GREEN (UPRR TO LARKIN CIR)  300 LF J&B under I-80 to the South  People’s Drain flow combined w/ NTD on the south side of UPRR  Stays in back yards of private property  Crosses Greg Street with 40’ deep open cut  Follows Larkin Circle to outfall at the Truckee River  Overall Length: ~ 5,900 feet ALIGNMENT 3 – BLUE (KLEPPE LN TO LARKIN CIR)  300 LF J&B under I-80 to the South  People’s Drain flow combined w/ NTD on the south side of UPRR  Alignment follows existing NTD to Kleppe Ln  From Kleppe Ln across parking lot to Greg St  Crosses Greg Street with 40’ deep open cut  Follows Larkin Circle to outfall at the Truckee River  Overall Length: ~ 5,300 feet

HDR | Presentation Alignment 2

HDR | Presentation Project Costs Costs presented are in million dollars and do not include land costs  Alignment 1 $67 Land Requirements (PERM)(TEMP)  UPRR 3.4 ac 6.0 ac  NDOT 2.9 ac 4.3 ac  Other Private 0.1 ac 0.9 ac  # Lots Impacted 1 5  Alignment 2 $45 Land Requirements  UPRR 0.4 ac 1.1 ac  NDOT 0.4 ac 0.6 ac  Other Private 3.0 ac 7.5 ac  # Lots Impacted  Alignment 4 $46 Land Requirements  UPRR 0.4 ac 1.2 ac  NDOT 0.4 ac 0.6 ac  Other Private 2.3 ac 6.2 ac  # Lots Impacted 15 23

HDR | Presentation North Truckee Drain Realignment Next Steps Value Engineering Analysis Environmental Assessment Utilities Geotechnical Engineering Surveying Right-of-Way Design Build vs Design Bid Build 104 Cost Sharing and Authorization

HDR | Presentation Questions

HDR | Presentation Current 100-yr Inundation

HDR | Presentation 2006 Storm Inundation