1. 1 Community Hydrology in a Watershed World The Fulton County Experience Amy Bergbreiter, PE, CFM Monica Urisko, PE, CFM

2. The Progression 2 Metro- Atlanta Studies September 2009 Flooding Georgia CTP Study PANIC STAGE Follow Guidelines and Specs Reach a Resolution

3. The Progression 3 Metro- Atlanta Studies September 2009 Flooding Georgia CTP Study PANIC STAGE Follow Guidelines and Specs Reach a Resolution

4. Metro Atlanta Studies 4 ● Metropolitan North Georgia Water Planning District model ordinances ● Communities have to regulate to the future conditions floodplain ● Applies to streams with a drainage area of 100 acres or greater ● 640 acre future conditions studies complete by 2013

5. Metro Atlanta Studies 5 ● 7 Communities within Fulton County had developed studies to comply ● 2 adjacent counties ● No correlation or connection between the communities

6. Metro Atlanta Studies 6 ● Different Times ● Different Models ● Different Contractors ● Different Methods within the Models ● Different Land Use ● Different Topographic Data Sources

7. The Progression 7 Metro- Atlanta Studies September 2009 Flooding Georgia CTP Study PANIC STAGE Follow Guidelines and Specs Reach a Resolution

8. September 2009 Flooding 8

9. The Progression 9 Metro- Atlanta Studies September 2009 Flooding Georgia CTP Study PANIC STAGE Follow Guidelines and Specs Reach a Resolution

10. Georgia CTP Study 10 ● All 159 counties were modernized by 2008 ● FY09 became a transition year ● Almost RiskMAP

11. Georgia CTP Study 11 ● Chattahoochee was the focus (107 miles) ● High Priority Sub-basins ● Incorporate New Topo ● Incorporate Available Studies ● Countywide/PMR

12. The Progression 12 Metro- Atlanta Studies September 2009 Flooding Georgia CTP Study PANIC STAGE Follow Guidelines and Specs Reach a Resolution

13. Panic Stage 13 ● 163 miles of FEMA funded detail study ● 285 detailed miles total ● 449 miles of FEMA funded approximate study ● 526 approximate miles total

14. Panic Stage 14 ● Eliminated the future only/no new survey studies ● 13 “Panic Points” ● Locations where two studies meet ● Always a CTP stream in between ● Different Issues at Different Locations

15. The Progression 15 Metro- Atlanta Studies September 2009 Flooding Georgia CTP Study PANIC STAGE Follow Guidelines and Specs Reach a Resolution

16. Follow Guidelines and Specifications 16 ● Appendix C applies ● Recently updated ● Guidance for reviewing ● Guidance for new studies ● Guidance for what is “significant”

17. Follow Guidelines and Specifications 17 1. Check one standard error 2. Check if in range of engineering practice 3. Issues should be justified

18. The Progression 18 Metro- Atlanta Studies September 2009 Flooding Georgia CTP Study PANIC STAGE Follow Guidelines and Specs Reach a Resolution

19. 19 ● Homes recently elevated to old BFE ● Highly urbanized area -so- ● Would always use the new study ● Would not adjust our studies just to tie in discharges

20. Reach a Resolution 20

21. The Progression 21 Metro- Atlanta Studies September 2009 Flooding Georgia CTP Study PANIC STAGE Follow Guidelines and Specs Reach a Resolution