1. Precipitation Frequency Estimates and Federal Responsibilities Geoff Bonnin NOAA’s National Weather Service Geoffrey.Bonnin@noaa.gov 301-713-0640 x103

2. Questions Is the Fed Gov’t responsible for estimates? Who should do it? –Regular document updates –Supporting research –Questions from the public Who should pay? How do we reach consensus and implement? Is the Fed Gov’t responsible for estimates? Who should do it? –Regular document updates –Supporting research –Questions from the public Who should pay? How do we reach consensus and implement?

3. Background? Early 1950s –NWS nominated to make estimates for: precipitation frequency probable maximum precipitation –Consensus of Federal water agencies –NWS is independent – doesn’t pour concrete De-facto National Standards –Referenced in federal, state, and local regulations –Traditional civil works to environmental management –Increasing demand for low frequencies; EPA’s NPDES Performed At Request Of And Funded By Users –not included in NWS budget Early 1950s –NWS nominated to make estimates for: precipitation frequency probable maximum precipitation –Consensus of Federal water agencies –NWS is independent – doesn’t pour concrete De-facto National Standards –Referenced in federal, state, and local regulations –Traditional civil works to environmental management –Increasing demand for low frequencies; EPA’s NPDES Performed At Request Of And Funded By Users –not included in NWS budget

4. Documents Are Getting Old 5 – 60 minutes1 – 24 hours2 – 10 days Western U.S.Frederick & Miller (1979) Arkell & Richards (1986) NOAA Atlas 2 (1973) Tech Paper 49 (1964) Eastern U.S.Tech Memo 35 (1977) Tech Paper 40 (1961) Tech Paper 49 (1964) HawaiiTech Paper 43 (1962) Tech Paper 43 (1962) Tech Paper 43 (1962) AlaskaTech Paper 47 (1963) Tech Paper 47 (1963) Tech Paper 52 (1965) Puerto RicoTech Paper 42 (1961) Tech Paper 42 (1961) Tech Paper 53 (1965)

5. What is NWS Doing?

6. New Capabilities in Use New technologies –Regional L-moments –Confidence intervals –Updating depth-area-reduction (1957) –Probalistic temporal distributions –High resolution mapping –Web based point and click delivery maps, charts, tables, GIS grids, documentation Much more data is available NWS integrated production line –Not a study – it is real Patchwork, piecemeal studies –Not cost effective –Produce inconsistent results NWS ready for cost effective national update –~$1m/yr over 3 years New technologies –Regional L-moments –Confidence intervals –Updating depth-area-reduction (1957) –Probalistic temporal distributions –High resolution mapping –Web based point and click delivery maps, charts, tables, GIS grids, documentation Much more data is available NWS integrated production line –Not a study – it is real Patchwork, piecemeal studies –Not cost effective –Produce inconsistent results NWS ready for cost effective national update –~$1m/yr over 3 years

7. Current Status Precip Frequency Atlas Updates –Semiarid Southwest published Aug 6 –Ohio Basin & Surrounding States peer review completed Sept 14 –Puerto Rico & Hawaii; FY2004 Probable Maximum Precipitation –No activity Funding Pipeline Has Dried Up NWS in danger of losing specialized expertise Precip Frequency Atlas Updates –Semiarid Southwest published Aug 6 –Ohio Basin & Surrounding States peer review completed Sept 14 –Puerto Rico & Hawaii; FY2004 Probable Maximum Precipitation –No activity Funding Pipeline Has Dried Up NWS in danger of losing specialized expertise

8. Requests From Alaska Dept of Transportation National Transportation Research Board Pacific Islands Colorado Twin Cities, Minnesota Wisconsin/Michigan Florida Counties New York FEMA State Climatologists Many Consultants Alaska Dept of Transportation National Transportation Research Board Pacific Islands Colorado Twin Cities, Minnesota Wisconsin/Michigan Florida Counties New York FEMA State Climatologists Many Consultants

9. Who Are the Federal Users? USACE - regulation & design FEMA – flood plain mapping EPA – pollution discharge regulation (NPDES) DOT/FHWA – hydrologic design USDA/NRCS – design & erosion control Forest Service – burned area remediation USBR – design ??? USACE - regulation & design FEMA – flood plain mapping EPA – pollution discharge regulation (NPDES) DOT/FHWA – hydrologic design USDA/NRCS – design & erosion control Forest Service – burned area remediation USBR – design ???

10. Options USACE continues funding Split equally among 5-6 agencies –~$200K/year Folded into key current programs –FEMA; Flood Plain Mapping Initiative –EPA; NPDES USACE continues funding Split equally among 5-6 agencies –~$200K/year Folded into key current programs –FEMA; Flood Plain Mapping Initiative –EPA; NPDES