September 20, 2012 TFMA 2012 Fall Conference, Rockwall, Texas

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1 September 20, 2012 TFMA 2012 Fall Conference, Rockwall, Texas

2 Martha Juch, P.E., CFM, D.WRE Project Director, AECOM Served as President of Upper Brushy WCID Board during T.S. Hermine Melinda Luna, P.E., CFM Team Lead, Floodplain Mapping Services TWDB/TNRIS

3 Two Year Anniversary of T.S. Hermine in Williamson County, Texas Brief Overview Review of process to request Disaster Declaration Damages sustained by communities Note: Presentation is a follow-up to TFMA Fall 2010 presentation by Martha Juch and Jay Scanlon, with many of the graphics/data from that presentation included

4 Tropical Storm Hermine September 7-9, 2010 Storm track through Texas, Oklahoma, Kansas, and Missouri Provided by Williamson County Emergency Management, July 2012

5 Tropical Storm Hermine September 7-8, 2010 Weather Underground Williamson County Rainfall Data Source: Williamson County Engineer, Sep. 2010

6 Tropical Storm Hermine September 7-8, 2010 NWS Radar Williamson County Rainfall Estimates

7 Tropical Storm Hermine September 7-8, 2010 NWS Radar Upper Brushy Creek Watershed Rainfall Estimates

8 Tropical Storm Hermine September 7-8, 2010 San Gabriel Unofficial Rainfall Data Extreme Rainfall inches in 26 hrs Bucket surveys inches

9 Tropical Storm Hermine September 7-8, 2010 Bucket Surveys North Georgetown Source: Williamson County Engineer, Sep. 2010

10 Tropical Storm Hermine September 7-8, 2010 Upper Brushy Creek Watershed Rainfall Data from UBC WCID gages at dams Sep. 2010

11 Tropical Storm Hermine September 7-8, 2010 UBC WCID Rainfall Data Rainfall Intensity Rainfall Total (inches) (inches/hr) Dam 1 hr 2 hr 3 hr 6 hr 12 hr 24 hr 1/4 Hr 1 hr MAX Sep. 2010

12 Tropical Storm Hermine September 7-8, 2010 Depth-Duration Frequency of Precipitation Storm Event (Return Period) Non-Exceedance Probability 2 50% 5 20% 10 10% 25 4% 50 2% 100 1% % % 100% PMF - Storm Duration (hours) Values in the table represent regional parameters near the centroid of the District. Values will vary slightly across the District Sep. 2010

13 Lesson Learned: Keep repeating the message: although rare, this flood is not unique Extreme Rainfall June 27, 2007 Marble Falls 1919 Austin, Texas 1873 Red River County, Texas

14 Tropical Storm Hermine in Texas A Presidential Disaster Declaration was requested but denied: FEMA toured Williamson County, one of 43 counties affected by the flooding from Tropical Storm Hermine. Federal threshold of 800 homes or substantial damages of $26.5 million in uninsured damages is required. Williamson County had difficulty getting homeowners to report damages, so values are probably underestimated. They also believe some neighboring counties failed to report damages to FEMA, causing the reported damages to erroneously fall short of the threshold. Governor requested disaster declaration, it was denied, he appealed, and it was denied again The Small Business Administration issued a disaster declaration for 18 counties in November 2012 to provide loans up to $200,000 for homeowners and up to $2 million for business owners

15 Williamson County: Extensive Flooding occurred in Williamson County County emergency management initially reporting 630+ homes had some damage Residential Statistics: Final count of 687 homes damaged 32 Destroyed (>48 Water) 150 Major Damage (24 48 Water) Remaining received substantial damage or were effected Public Facilities Sustaining Damages: County estimated $1,459,728 in damages to county roads (erosion, pavement, shoulders, ditches, etc.)

16 Williamson County Flooding Sep. 2010

17 Williamson County Flooding Williamson County Office of Emergency Management

18 Example of Flooding in Williamson County: Brushy Bend Park subdivision 11:15 a.m. Sept 8 High water approx. 3 ft.

City of Round Rock: Extensive Flooding in Upper Brushy Creek watershed City Building Inspection report: 84 homes damaged Residential Statistics: 21 homes had flooding less than one foot in depth, two

19 City of Round Rock: Extensive Flooding in Upper Brushy Creek watershed City Building Inspection report: 84 homes damaged Residential Statistics: 21 homes had flooding less than one foot in depth, two of these have not been repaired 53 homes had flooding between one and three feet, five were demolished and 48 have been repaired 10 homes had flooding more than three feet deep, one of these was demolished and the rest repaired

20 City of Round Rock (continued): Residential Statistics: Damages between $2,500 and $80,000. Average damage of $46,130 Total residential damages $3.6 million All damages less than 50% of home value Public Facilities Sustaining Damage: Off-line West WWTP which will be rehabilitated and moved out of the floodplain Off-line lift station that has now been abandoned, and the downtown well site Parks facility which will be rebuilt to current regulations

21 City of Round Rock (continued): Recovery assistance in addition to Emergency Services: Shelter Waived permit fees Provide victim resources and temporary housing Coordinate volunteer demolition and clean up labor forces Curbside trash and debris pickup Street closures and increased police patrols

East Round Rock @ Brushy Creek - Before the Flood House built in 1976, 3 bedroom, 2 bath Current

22 East Round Brushy Creek - Before the Flood House built in 1976, 3 bedroom, 2 bath Current owners have lived here since 1981 No previous flooding Not in a Special Flood Hazard Area No Flood Insurance

East Round Rock @ Brushy Creek - The Day

23 East Round Brushy Creek - The Day after the Flood Approximately one foot of water in the house Three feet of water in the wood working shop in the backyard

East Round Rock @ Brushy Creek Interior with damages Flooding occurred at

cabinets, doors, appliances, furniture, and personal belongings Homeowners

24 East Round Brushy Creek Interior with damages Flooding occurred at night and was very fast Waters receded quickly, damaging sheet rock, floors, cabinets, doors, appliances, furniture, and personal belongings Homeowners (in their 70 s) waded in the dark through waste-deep water in the street to evacuate

25 East Round Brushy Creek Cleanup begins Family members helped with clean up and demolition The City provided dumpsters and heavy equipment Volunteers showed up to help

East Round Rock @ Brushy Creek Repairs w/o Insurance Repairs cost $70,000, paid for

26 East Round Brushy Creek Repairs w/o Insurance Repairs cost $70,000, paid for out of homeowners savings; plus rented apartment for six months Replaced all sheetrock below 4 ft., kitchen and bathroom cabinets, floors, beds, bookcases and other furniture, doors, items in wood shop, garage cabinets; also made repairs to cars and appliances

27 East Round Brushy Creek Things that can t be replaced Books, photo albums, artwork stored on the floor or in bottom cabinets and shelves

28 East Round Brushy Creek - Neighbors Both neighbors across the street also did not have flood insurance and have slowly been making their own repairs during the last two years

29 City of Round Rock Residential Flooding Sep 2010

30 City of Cedar Park: Extensive Flooding occurred in the Upper Brushy Creek watershed in the City of Cedar Park 85 structures reported some damage Residential Statistics: 83 homes reported flooding 79 homes had flooding of less than one foot in depth 2 homes had flooding between 1 and 3 feet 2 homes had flooding greater than 3 feet in depth; these homes were located in a dam inundation easement and were flooded for hours All homes were repaired and sustained damages less than 50% of the home value

31 City of Cedar Park (continued): Public Facilities Sustaining Damages: 2 public structures (park facilities) reported flooding one park structure had flooding between 1 and 3 feet one park structure had flooding greater than 3 feet in depth Park repairs were estimated at over $100,000. A wastewater main collapsed due to inundation Total cost of repairs to public facilities and erosion/debris issues in public ROW is estimated at $984,000.

32 City of Cedar Park - Brushy Creek Lake Park Lake rose to bottom of bridge beam at Parmer Road, inundating park facilities and paths 11:30 a.m. Sept. 8

33 City of Cedar Park - Brushy Creek Lake Park Lake returned to normal level within three to four weeks 11:30 a.m. Oct. 5

34 City of Cedar Park - Brushy Creek Lake Park near the Dam

35 City of Georgetown: Extensive Flooding occurred along the San Gabriel River and tributaries in the City of Georgetown Emergency Management Coordinator reported more than 120 structures in Georgetown had some damage, including homes, businesses, schools and public buildings Statistics 120 structures damaged, including homes in the Berry Creek, Quail Valley and Sun City neighborhoods City and the Red Cross provided an emergency shelter, and volunteers helped with flood damage cleanup N. Austin Avenue was closed temporarily with pavement damage Two parks were inundated along the River

Upper Brushy Creek Water Control and Improvement District (UBC WCID) Maintains 23 NRCS (formerly SCS) dams in Upper Brushy Creek watershed 6 auxiliary spillways engaged Dam 3, Dam 4, Dam 6, Dam 7,

36 Upper Brushy Creek Water Control and Improvement District (UBC WCID) Maintains 23 NRCS (formerly SCS) dams in Upper Brushy Creek watershed 6 auxiliary spillways engaged Dam 3, Dam 4, Dam 6, Dam 7, Dam 8, Dam 13A First recorded discharge through auxiliary spillways Repairs Needed at 4 Dams Minor Erosion Dam 4, 6, 7 Auxiliary Spillways Minor Surface Slides - Dam 13A Total cost for UBC WCID repairs = $750,000

37 Example of UBC WCID Dam with damages Dam 4

38 Dam 4 with Emergency Spillway engaged

39 Damage to private road at bottom of Dam 4 emergency spillway

40 NFIP Claims in Williamson County Before Hermine Hermine 2010 Event (9/7-8/10) City/County Claims Total Losses Paid Claims Total Losses Paid Bartlett 0 $0 0 $0 Cedar Park 20 $148, $547,927 Florence 7 $91,945 3 $57,086 Georgetown 8 $64, $1,653,832 Granger 7 $207,217 0 $0 Hutto 0 $0 0 $0 Leander 12 $357,795 3 $234,278 Liberty Hill 0 $0 0 $0 Round Rock 128 $1,101, $3,534,612 Taylor 16 $109,043 0 $0 Thrall 0 $0 0 $0 Weir 0 $0 0 $0 Williamson County 125 $1,872, $4,631,613 T o t a l 323 $3,952, $10,659,348

41 Two Year Anniversary of T.S. Hermine in Williamson County, Texas Summary Williamson County reported 687 homes were damaged by floodwaters, but we know that not all homeowners completed surveys or reported damages 208 homeowners (30%) filed flood insurance claims for a total of $10.7 million. Average cost per claim = $51,246 Cities reported that many homeowners flooded who did not have flood insurance, primarily attributed to no requirement by mortgage company (either not in mapped floodplain or home paid for in full by owner)

42 Two Year Anniversary of T.S. Hermine in Williamson County, Texas Summary Threshold for Presidential Disaster Declaration of $26.5 million was not met; however, damages were probably under reported Millions in damages to county roads, park facilities and utilities were reported in Williamson County, but other adjacent affected counties failed to report damages. If 687 homes had an average of $51,246 in damages, total residential damages should have been close to $35.2 million in Williamson County alone. Without federal assistance, 2 years later numerous homes have not been fully repaired

43 T.S. Hermine in Williamson County, Texas Future Impacts Some of the damaged utilities in the cities were moved out of the flood hazard areas. None of the homes flooded in Round Rock and Cedar Park (where we had detailed data) were substantially damaged, so the requirements for mitigation to higher standards was not applied. A new watershed based study of the Upper Brushy Creek basin will result in new floodplain maps (2015?), but no other studies or mapping efforts are occurring in the County.

44 Questions Martha Juch, P.E., CFM, D.WRE Project Director, AECOM President of Upper Brushy WCID Board of Direction during TS Hermine Melinda Luna, P.E., CFM Team Lead, Floodplain Mapping Services TWDB/TNRIS

45 Future Events

Ecological Context - Urban settlements are part of their surrounding ecosystem. Austin

Ecological Context - Urban settlements are part of their surrounding ecosystem Austin Ecotone Division between West and East Flyway Uplift River Balcones Escarpment Central Texas Climate The principal