City of Reno’s Drainage Needs Beyond TRFMA Project Components John Flansberg, P.E, Director Public Works A Presentation for the Truckee River Flood Project Needs Committee: January 3, 2019
Northern Nevada Atmospheric River: January 8, 2017 Truckee River: 12,200 CFS 12.12 feet at Reno gage National Weather Service 24-hour totals: 2” precip for Reno 3” Caughlin Ranch FEMA Claims For Northern Nevada FEMA Claims For Northern Nevada ~ $30 million for Two Disasters ~ $30 million for Two Disasters 2
January 8, 2017 Reported Flooding Locations 3
Before the Event Public Works: Inspected and cleared debris (storm drains, drop inlets, intakes and culverts) Inspected high hazard dams Coordinated with Associated General Contractors Installed a barrier rail along the river at the Grand Sierra resort to protect the airport Rented equipment excavators, loaders, backhoes, light plants, message boards Pre-filled approximately 40,000 sand bags: established and stocked additional sandbag distribution stations Closed bridges over the Truckee River Coordinate with Sparks and Washoe County Established cost tracking accounts 4
During the Storm / Flood Response Monitored high hazard dams Inspected and monitored 8 scour critical bridges Closed roads Delivered several trucks of sandbags to Sagittarius / Aquila and crews built several walls of sandbags 5
Sierra St. between N. Virginia St. and 15th St. S. Virginia north of South Meadows Parkway to near Patriot Blvd. Offenhauser Dr. at Portman Ave. Aquila Ave. : Plumb Ln. to Thomas Jefferson Dr. 9th St. between Lake St. and Evans Ave. Gateway Dr. at Offenhauser Dr. South Meadows Pkwy: Double Diamond Pkwy to Wilbur May US 395A : East Lake Blvd to Mt. Rose Hwy Rosewood Lakes area off of Mira Loma and adjacent Boynton Slough McCarran Drive: Mill Street to Mira Loma 6
Recovery-Damage Assessments Working with the State Dept. of Emergency Management and FEMA Public Works provided damage assessments for 66 locations where debris removal or damage repairs are needed Public assistance costs Reno requested $4.85 Million For the region the damage assessment was $15- 17 Million The estimated flood response and preparations costs for City of Reno were approximately $2 Million 7
Autumn Hills-Brunson Branches of Thomas Creek Conveyance system at capacity (designed for 10 yr event) Lift station flooded Voluntary evacuation 8
Sagittarius-Aquila Steamboat ditch overtopped in several locations and sent water down Sagittarius Dr, Aquila Ave., Plumb Ln, Krupp Cir., Thomas Jefferson and Pass Dr. Roadside ditch on Sagittarius experienced erosion and damage to driveways and landscaping Debris was carried from Sagittarius, down Aquila, and Plumb Lane Underground facilities were exposed in several locations 9
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Flooding “Hot Spots”- Ditch Influences 12
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Sagittarius –Aquila Erosion/Overtopping: Mitigation after event 15
Sagittarius –Aquila Erosion/Overtopping: Mitigation after event 16
Lake Ditch breach: Brighton Manor 17
Brighton Manor Brighton Manor -Single Family Homes located adjacent to Lake Ditch Recent construction--homes have been occupied for less than 2 years. 18
McCarran at Rio Poco 19
McCarran at Rio Poco Erosion to landscaping and channel, undermined power box,debris on Rio Poco Intersection of Rio Poco Rd. and Snowshoe Lane covered with mud and debris 20
Edison Way Truckee River / Steamboat Creek influence. North Edison is low and adjacent to river Extensive amounts of debris over N. Edison Ditch system in the Capital Blvd. and Corporate Blvd. area: damage to the banks and eroded culvert headwalls Portions of Corporate Blvd were covered with debris 21
Omaha Drive 22
Lemmon Valley Drive 23
December 31, 2005 Atmospheric River and antecedent moisture/snow set up region for large runoff. Truckee River crested at 16,400 cfs, 13.4 feet at the Reno gage Similar flood reports- Irrigation Ditch breaches Autumn Hills Sagittarius – Aquila North Valleys Steamboat Creek McCarran at Mira Loma 24
Irrigation Ditches-Past and Current Practice The irrigation ditches are a legacy of City’s history dating back to 1800’s Privately owned, the 4 primary ditches are: Steamboat, Last Chance, Lake, Cochrane (City of Reno owns portions) Constructed as agricultural facilities, City has agreements with ditch companies to utilize as storm conveyance: City reimburses ditch companies on pro-rata basis for stormwater related expenses None of the irrigation ditches has the capacity to convey flow from a design event (i.e., the 100 year storm) Urbanization has turned previously unnoticed ditch overtopping/breaching into a flooding issue No new connections since 2002 25
City of Reno “other areas” Summary Big Tickets: Autumn Hills: $10 million Ditch bypass structures and storm drain solutions $21 million Dant Wash: $9 million Master Planning: $2.5 million Stead Channel improvements: $7 million …. And more Total City of Reno “other areas” identified ~ $158 Million 26
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