1

ROCK RIVER FLOOD

INUNDATION MAPPING PROJECT

November 5, 2015

Roxanne GrayMitigation Section Supervisor

Wisconsin Emergency Management

Chris OldsFloodplain Engineer

Wisconsin Department of Natural Resources

What is it?

• Development of map libraries that contains a series of sequential maps that help communicate where flooding may occur over a range of river levels

• Connected to real-time and forecasted river levels at USGS streamgages

• Utilized for preparedness, timely response, recovery, mitigation and planning, environmental and ecological assessments

2

Background

• WDNR, WEM, and USGS met December 2012 to discuss a pilot flood inundation mapping project in the state

• Due to the flood risk, LIDAR, flood modeling, and mitigation activities selected the Rock River

• Reached out to Dodge, Jefferson and Rock Counties in January 2013 to determine local interest

• Stakeholders meeting held in April 2013 in Jefferson

3

Invited Stakeholders

4

• WDNR

• WEM

• DOT

• DOA

• WEDC

• Officials from Dodge, Jefferson, and Rock Counties

• USACE

• NWS

• USGS

• FEMA

• Association of StateFloodplain Managers

FRMP Proposal

• USACE call for proposals February 13, 2013

• WEM, WDNR, USGS, USACE and NWS

• Submitted April 3, 2013

• Shared proposal at the stakeholders meeting on April 23rd

• Some modifications to proposal

• Notified April 21, 2014 proposal accepted

• Included 5 reaches for flood inundation libraries on the Rock River covering 38 miles

5

Outcomes

• User-friendly visual tool to understand potential impacts of flooding enabling local officials and property owners to make informed decisions to:• Mitigate flood risk

• Respond to flooding

• Promote preparedness

• Improve protective measures and evacuation options prior to floods

• Identify cost-effective mitigation measures, thus lowering future response, repair and recovery costs

6

Inundation Locations

7

Base Data

• Rock River hydraulic model created for FEMA’s RiskMap project in the Rock River watershed

- survey completed in spring of 2010

- model effective in Dane on 9/17/14, Dodge 5/19/14, Jefferson 2/4/15, Rock 9/16/15

• Terrain data from each county

-Dane 2009, Dodge 2006, Jefferson 2012, Rock 2011

8

Calibration of Model

• Jefferson, Fort Atkinson and Lake Koshkonong gages will use the new model for basis of an updated rating curve

• Afton and Watertown locations in the model had to be adjusted so the model matched existing rating curves within 0.5’

9

Web Location

Search “nws inundation”

10

Web Location

Within the NWS site

11

Web location

http://water.weather.gov/ahps/inundation.php

12

Individual Site Example

13

Individual Site Example

14

Individual Site Example

15

Individual Site Example

16

Basemap choices

Individual Site Example

17

Basemap choices

Individual Site Example

18

Depth of flooding

Individual Site Example

19

Depth of flooding

Individual Site Example

20

Individual Site Example

21

Depth of flooding

Individual Site Example

22

Map overlays - NFHL

Individual Site Example

23

Map overlays - transparency

Individual Site Example

24

Other flood data

Individual Site Example

25

Other flood data

Individual Site Example

26

Download data

Individual Site Example

27

Download data

Links

http://water.weather.gov/ahps2/inundation/index.php?gage=aftw3

http://water.weather.gov/ahps2/inundation/index.php?gage=fatw3

http://water.weather.gov/ahps2/inundation/index.php?gage=jffw3

http://water.weather.gov/ahps2/inundation/index.php?gage=nvlw3

http://water.weather.gov/ahps2/inundation/index.php?gage=watw3

28

Contact Info

Roxanne GrayWisconsin Emergency Management

Mitigation SectionRoxanne.Gray@wisconsin.gov

608-242-3211

Chris OldsWisconsin Department of Natural Resources

Bureau of Watershed Management/Dam Safety & Floodplain Section

Christopher.Olds@Wisconsin.gov608-266-5606

29