Wastewater Treatment Works Compliance Maintenance Program

Precipitation Data

eCMAR Section m: Sanitary Sewer Collection Systems, requires that you enter precipitation data in question #5. You are asked to enter the “Total Actual Amount of Precipitation Last Year”, and the “Annual Average Precipitation (for your location).” Listed below are descriptions of this data and where to find them.

Total Actual Amount of Precipitation

Total precipitation is the entire amount of precipitation (including snow equated to a water equivalent) that has fallen for the calendar year (January 1 through December 31, 2008). Precipitation data you have collected or from other sources such as the Wisconsin State Climatology Office, National Weather Service, local airport or other approved source of precipitation information within close proximity of your facility’s location for the 2008 calendar year is acceptable. Enter the Total Actual Amount of Precipitation in question #5 of the collection system section of your eCMAR. Sources of data are:

• 2008 Wisconsin State Climatology Office Data (24KB PDF file, 5 pgs.)

  Select your community (if listed) and associated precipitation data.

• National Weather Service Data at: http://hurricane.ncdc.noaa.gov/ancsum/ACS (exit DNR in new window)

  NOTE: requires a nominal fee of $2 per weather station.

• Local weather station data from Weather Underground at: http://www.wunderground.com/ (exit DNR in new window).

  To navigate this site, follow these steps:

  • Type in the City, WI for your community at the very top of the webpage and click on the magnifying glass icon.
  • Scroll down to the “Weather Stations” table at the bottom of the page and click on the link closest to your facility.
  • Daily summary data for this location will appear. There are tabs across the screen labeled “ Daily”, “Weekly”, “Monthly’, “Yearly”, and “Custom.” Click on the “Custom” tab.
  • On the “Custom Summary” screen select the dates January 1, 2008 to December 31, 2008 and the “Go” button. Yearly precipitation data will appear if there is sufficient data.

  If a nearby weather station does not have 12 months of precipitation data, then choose another weather station nearby that does.

Annual Average (Historical) Precipitation

Use data from your closest weather station or a nomograph to find the annual average precipitation. The Wisconsin State Climatology Office web site contains both sources of data. Enter the Annual Average Precipitation data in question #5 of the collection system section of your eCMAR. Sources of data are:

• Closest Weather Station

  Use the Wisconsin State Climatology Office web site address: http://www.aos.wisc.edu/~sco/clim-history/by-location/index.html (exit DNR in new window)

  Click on the station closest to your facility. Scroll down to the bottom of the page and click on the “Precipitation” link. The very top line gives you the long term Annual Average Precipitation amount for that station by month with the Annual Average under the heading “ANN.”

• Nomograph

  You may use the nomograph the Wisconsin State Climatology Office provides on their web site at: http://www.crh.noaa.gov/mkx/climate/wipcpn.gif (exit DNR in new window)

  Approximate the location of your community on the state map. Read the nomograph lines closest to your community, and extrapolate between them if necessary. Select the corresponding amount of precipitation in inches from the color-coded explanation.