# Presentation: 763321

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

## 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?**

## 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***

## Documents Are Getting Old

|  | 5 – 60 minutes | 1 – 24 hours | 2 – 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) |
| Hawaii
 | Tech Paper 43
(1962) | Tech Paper 43
(1962) | Tech Paper 43
(1962) |
| Alaska | Tech Paper 47
(1963) | Tech Paper 47
(1963) | Tech Paper 52
(1965) |
| Puerto Rico | Tech Paper 42
(1961) | Tech Paper 42
(1961) | Tech Paper 53
(1965) |

## What is NWS Doing?

**What is NWS Doing?**

## 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***

## 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**

## 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**

## 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**
**???**

## Options

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