Identification_Information: Citation: Citation_Information: Originator: Silvia Terziotti Publication_Date: 2009 Title: precipsw Edition: Version 1.0, June 30, 2009 Geospatial_Data_Presentation_Form: raster digital data Publication_Information: Publication_Place: Raleigh, NC Publisher: U.S. Geological Survey Online_Linkage: \\Igsavbewfs001\Work\SWAP_updates\FinalLayers\SW\precipsw Description: Abstract: Average annual precipitation classes to characterize watersheds is one of 6 data sets updated for the North Carolina Public Water Supply, Source Water Assessment Program. These data are used to rate the susceptibility of public water supplies in North Carolina to contamination. The original dataset was produced in 2000. This version is updated to reflect new data sources. This data set represents the ratings applied to the average annual precipitation classes for use in the rating of the watershed characteristics for surface-water suppliers. Average annual precipitation is used as a measure of the amount of water (with or without contaminants) that travels as runoff or through the shallow subsurface to streams or lakes. For surface-water systems, the greater the average annual precipitation, the higher the rating applied on a scale of 1 to 10. Purpose: This data set is to be used in a hydrologic analysis with other data sets to rate the unsaturated zone for public ground-water supplies and watershed characteristics for public surface-water supplies in North Carolina. For ground-water supplies, the factors used to rate susceptibility to contamination include vertical hydraulic conductance, land-surface slope, land cover, and land use. The selected factors used to devise ratings for surface-water supplies' susceptibility to contamination are average annual precipitation, land-surface slope, land cover, land use, and ground-water contribution. Supplemental_Information: The 1996 Amendments to the Safe Drinking Water Act require that each state prepare a source-water assessment for all public water supplies. States are required to (1) delineate source areas supplying wells and surface-water intakes, (2) inventory potential contaminant sources within the delineated source areas, and (3) determine the susceptibility of wells or intakes to the inventoried potential contaminant sources. In North Carolina, the lead agency charged with this task is the Public Water Supply Section (PWSS) of the Division of Environmental Health, Department of Environment and Natural Resources (DENR). North Carolina's Source Water Assessment Program (SWAP) provides assessments of each public drinking water intake in North Carolina. These assessments provide a relative susceptibility rating calculated using state-wide data. The U.S. Geological Survey (USGS) cooperated with the PWSS to provide components of the inherent vulnerability rating that was used with the contaminant rating to determine the overall susceptibility rating of source water supplies. To assist the PWSS with rating ground water inherent vulnerability, the USGS compiled the unsaturated zone rating based on the following characteristics: vertical hydraulic conductance, depth to water, land surface slope, land use and land cover. The watershed characteristic rating includes average annual precipitation, land surface slope, land use, land cover and groundwater contribution. The SWAP program has planned for updates to the initial ratings as conditions change and new data sources become available. The initial data used to calculate the unsaturated zone ratings and watershed characteristics ratings were compiled from sources from the late 1990's. Critical data layers have been updated since the ratings were calculated. These improved data layers need to be used in the ongoing update of the susceptibility ratings. Overlay and index methods for rating susceptibility to contamination of the unsaturated zone for ground-water suppplies, and watershed characteristics for surface-water supplies were derived for use by the State of North Carolina in assessing more than 11,000 public water-supply wells and approximately 245 public surface-water intakes. Factors that influence the inherent vulnerability of ground water and surface water were selected and assigned ratings on a scale of 1 to 10. These factors were then assigned weight to reflect their relative influence on inherent vulnerability and the reliability of the data. The values for each factor were obtained from geographic information system (GIS) data layers that were transformed into ARC/INFO raster data sets known as grids. These raster data sets have 30-meter by 30-meter cells, and each cell is assigned a weighted- factor value. Limitations -- The overlay and index methods of unsaturated zone and watershed characteristics ratings are broad-stroke methods that assess vulnerability on the basis of expert opinion. The methods aslo have limitations in the age and scale of the hydrologic and geographic data. But the most significant limitation of the methods used is that no statistical confirmation of the results have been performed. AVERAGE ANNUAL PRECIPITATION: Precipitation is a surrogate measure of the volume of water transported to surface-water intakes, with or without contaminants. In North Carolina, average annual precipitation varies from about 37 inches to more than 97 inches. Most of the variation occurs in the Blue Ridge Mountains, with the highest and lowest amounts occurring in this area. Determination of average annual precipitation is based on the recently-developed Parameter-elevation Regressions on Independent Slopes Model (PRISM), which uses land-surface elevation to estimate precipitation in areas not covered by weather observation stations (Daly, 1996). Average annual precipitation values, based on data collected from 1971 to 2007 at about 140 observation stations in North Carolina, are the input data to the PRISM model. The average annual precipitation was updated to reflect a more recent period of record. The annual average precipitation rating in 2000 was based on the years 1961 through 1990. The current data set covers the period 1971 to 2007. This reflects changes from recent hurricanes as well as two major droughts that occurred in N.C. during 1998-2002 and again in 2008 (McSwain, K.B., and Weaver, J.C., 2008, Effects of the current drought on streamflow and ground-water conditions in North Carolina: Charlotte, NC, Geological Society of America Southeastern Section Meeting [abs].; and Weaver, J.C., 2005, The drought of 1998-2002 in North Carolina—Precipitation and hydrologic conditions: U.S. Geological Survey Scientific Investigations Report 2005-5053, 88 p.) There was an increase in tropical storm and hurricane activity that affected North Carolina during this period. According to the State Climate Office of North Carolina, 38 tropical storms or hurricanes affected North Carolina during the period 1971 to 2007. There were only 19 during the period 1961 to 1990 (http://www.nc-climate.ncsu.edu/climate/hurricane.php). Average annual precipitation was categorized by increments of 5 inches, from less than 40 inches to more than 80 inches. Two-thirds of the State receives between 40 and 50 inches of rainfall during the year and have a precipitation rating of 2 or 3. Average annual precipitation amounts exceeding 80 inches are rated 10. The upper threshold of 80 inches was chosen because very few water-supply systems have watersheds located solely where rainfall exceeds this amount. Average annual precipitation categories and rating for watershed characteristics rating: >Average annual precipitation, Percent of area Rating >in inches in North Carolina > >Less than or equal to 40 1 1 > >Greater than 40 to 39 2 >less than or equal to 45 > >Greater than 45 to 32 3 >less than or equal to 50 > >Greater than 50 to 19 4 >less than or equal to 55 > >Greater than 55 to 7 5 >less than or equal to 60 > >Greater than 60 to 1 6 >less than or equal to 65 > >Greater than 65 to 1 7 >less than or equal to 70 > >Greater than 70 to less than 1 8 >less than or equal to 75 > >Greater than 75 to less than 1 9 >less than or equal to 80 > >Greater than 80 1 10 SELECTED REFERENCES: Daly, C., 1996, Overview of the PRISM model, PRISM Climate Mapping Program: accessed March 18, 1999, at URL http://www.ocs.orst.edu/prism/prism_new.html Daly, C., Neilson, R. P. and Phillips, D. L., 1994, A statistical- topographic model for mapping climatological precipitation over mountainous terrain: Journal of Applied Meteorology 33: p. 40-158. Eimers, J. L., Weaver, J. C., Terziotti, S., and Midgette, R. W., 2000, Methods of rating unsaturated zone and watershed characteristics of public water supplies in North Carolina: U. S. Geological Survey Water-Resources Investigations Report 99-4283, 31 p. North Carolina Department of Environment and Natural Resources, 1999, North Carolina source water assessment program plan: Raleigh, North Carolina Department of Environment and Natural Resources, Division of Environmental Health, Public Water Supply Section, [variously paged]. For more information on PRISM data see: Daly, C., 1996, Overview of the PRISM model: accessed March 18, 1999, at URL http://www.ocs.orst.edu/prism/prism_new.html DISCLAIMER: Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this Federal Geographic Data Committee-compliant metadata file is intended to document the data set in nonproprietary form, as well as in ARC/INFO format, this metadata file may include some ARC/INFO-specific terminology. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1971 - 2007 Currentness_Reference: Based on 20 years of record Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -84.907009 East_Bounding_Coordinate: -75.307866 North_Bounding_Coordinate: 37.554514 South_Bounding_Coordinate: 33.052474 Keywords: Theme: Theme_Keyword_Thesaurus: none Theme_Keyword: Precipitation Theme_Keyword: Rainfall Theme_Keyword: Vulnerability Theme_Keyword: Ratings Place: Place_Keyword_Thesaurus: none Place_Keyword: North Carolina Access_Constraints: none Use_Constraints: These data are not to be used for site specific analysis Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Silvia Terziotti Contact_Organization: U.S. Geological Survey Contact_Position: Computer Specialist Contact_Address: Address_Type: mailing address Address: 3916 Sunset Ridge Road City: Raleigh State_or_Province: NC Postal_Code: 27607 Country: USA Contact_Voice_Telephone: (919) 571-4000 Contact_Facsimile_Telephone: (919) 571-4041 Contact_Electronic_Mail_Address: (seterzio@usgs.gov) Data_Set_Credit: The authors are grateful to colleagues in the Public Water Supply Section of the Division of Environmental Health, North Carolina Department of Environment and Natural Resources (DENR) for their assistance in this collaborative project: thanks to Robert Midgette, Protection and Enforcement Branch Head; Amy Axon,hydrogeologist - Source Water Protection; and David Hammermann, Geographic Information Systems Specialist. The authors also thank the USGS report review team for their review of the update procedures: Jeanne Robbins, Surface-water Specialist; Melinda Chapman, Ground-water Specialist; Mary Giorgino, Water-quality Specialist; and Douglas Harned, ALBE-National Water Quality Assessment Project Chief. Native_Data_Set_Environment: Microsoft Windows 2000 Version 5.2 (Build 3790) Service Pack 2; ESRI ArcCatalog 9.2.6.1500 Cross_Reference: Citation_Information: Originator: Silvia Terziotti and Jo Leslie Eimers Publication_Date: 2001 Title: Watershed Characteristics Rating for North Carolina Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: USGS Open-File Report Issue_Identification: USGS OFR 01-490 Publication_Information: Publication_Place: Raleigh, NC Publisher: USGS Online_Linkage: http://nc.water.usgs.gov/reports/ofr01490/index.html Cross_Reference: Citation_Information: Originator: Silvia Terziotti and Jo Leslie Eimers Publication_Date: 2001 Title: Unsaturated Zone Characteristics Rating for North Carolina Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: USGS Open-File Report Issue_Identification: USGS OFR 01-489 Publication_Information: Publication_Place: Raleigh, NC Publisher: USGS Online_Linkage: http://nc.water.usgs.gov/reports/ofr01489/index.html Cross_Reference: Citation_Information: Originator: Silvia Terziotti and Jo Leslie Eimers Publication_Date: 2001 Title: Land-Use Classes to Characterize Watersheds and the Unsaturated Zone in North Carolina Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: USGS Open-File Report Issue_Identification: USGS OFR 01-493 Publication_Information: Publication_Place: Raleigh, NC Publisher: USGS Online_Linkage: http://nc.water.usgs.gov/reports/ofr01493/index.html Cross_Reference: Citation_Information: Originator: Silvia Terziotti and Jo Leslie Eimers Publication_Date: 2001 Title: Land-Cover Classes to Characterize the Unsaturated Zone in North Carolina Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: USGS Open-File Report Issue_Identification: USGS OFR 01-491 Publication_Information: Publication_Place: Raleigh, NC Publisher: USGS Online_Linkage: http://nc.water.usgs.gov/reports/ofr01491/index.html Cross_Reference: Citation_Information: Originator: Silvia Terziotti and Jo Leslie Eimers Publication_Date: 2001 Title: Percent-Slope Classes to Characterize the Unsaturated Zone in North Carolina Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: USGS Open-File Report Issue_Identification: USGS OFR 01-495 Publication_Information: Publication_Place: Raleigh, NC Publisher: USGS Online_Linkage: http://nc.water.usgs.gov/reports/ofr01495/index.html Cross_Reference: Citation_Information: Originator: Jo Leslie Eimers, Silvia Terziotti and Gloria Ferrell Publication_Date: 2001 Title: Vertical Series Hydraulic Conductance Classes to Characterize the Unsaturated Zone in North Carolina Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: USGS Open-File Report Issue_Identification: USGS OFR 01-486 Publication_Information: Publication_Place: Raleigh, NC Publisher: USGS Online_Linkage: http://nc.water.usgs.gov/reports/ofr01486/index.html Cross_Reference: Citation_Information: Originator: Jo Leslie Eimers, Silvia Terziotti and Mary Giorgino Publication_Date: 2001 Title: Estimated Depth to Water, North Carolina Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: USGS Open-File Report Issue_Identification: USGS OFR 01-487 Publication_Information: Publication_Place: Raleigh, NC Publisher: USGS Online_Linkage: http://nc.water.usgs.gov/reports/ofr01487/index.html Cross_Reference: Citation_Information: Originator: Silvia Terziotti and Jo Leslie Eimers Publication_Date: 2001 Title: Land-Cover Classes to Characterize Watersheds in North Carolina Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: USGS Open-File Report Issue_Identification: USGS OFR 01-492 Publication_Information: Publication_Place: Raleigh, NC Publisher: USGS Online_Linkage: http://nc.water.usgs.gov/reports/ofr01492/index.html Cross_Reference: Citation_Information: Originator: Silvia Terziotti and Jo Leslie Eimers Publication_Date: 2001 Title: Average Annual Precipitation Classes to Characterize Watersheds in North Carolina Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: USGS Open-File Report Issue_Identification: USGS OFR 01-494 Publication_Information: Publication_Place: Raleigh, NC Publisher: USGS Online_Linkage: http://nc.water.usgs.gov/reports/ofr01494/index.html Cross_Reference: Citation_Information: Originator: Silvia Terziotti and Jo Leslie Eimers Publication_Date: 2001 Title: Percent-Slope Classes to Characterize Watersheds in North Carolina Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: USGS Open-File Report Issue_Identification: USGS OFR 01-496 Publication_Information: Publication_Place: Raleigh, NC Publisher: USGS Online_Linkage: http://nc.water.usgs.gov/reports/ofr01496/index.html Cross_Reference: Citation_Information: Originator: Silvia Terziotti and Jo Leslie Eimers Publication_Date: 2001 Title: Ground-Water Contribution Classes to Characterize Watersheds in North Carolina Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: USGS Open-File Report Issue_Identification: USGS OFR 01-488 Publication_Information: Publication_Place: Raleigh, NC Publisher: USGS Online_Linkage: http://nc.water.usgs.gov/reports/ofr01488/index.html Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The values for average annual rainfall are consistent with other Weather Service maps showing rainfall patterns. Logical_Consistency_Report: Not applicable for raster data. Completeness_Report: The data is available for all of N.C. and adjacent States. As updated data is available for more recent period of record, this data set could be updated. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: No checks were made on horizontal accuracy other than visual checks with other data sources mapped at similar scales. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Chris Daly, Oregon State University Originator: George Taylor, Oregon Climate Service at Oregon State University Publication_Date: 199804 Title: North Carolina Average Monthly or Annual Precipitation, 1961-90 Geospatial_Data_Presentation_Form: map Publication_Information: Publication_Place: Portland, Oregon, USA Publisher: Water and Climate Center of the Natural Resources Conservation Service Source_Scale_Denominator: 800 m Type_of_Source_Media: online Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1971 - 2007 Source_Currentness_Reference: NOAA Weather Station period of record Source_Citation_Abbreviation: none Source_Contribution: average annual precipitation Source_Information: Source_Citation: Citation_Information: Originator: Daly, C. Publication_Date: 1996 Title: Overview of the PRISM model, PRISM Climate Mapping Program Series_Information: Series_Name: URL http://www.ocs.orst.edu/prism/prism_new.html Issue_Identification: accessed March, 1999 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1996 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Daly (1996) Source_Contribution: methods used to generate model Source_Information: Source_Citation: Citation_Information: Originator: Daly, C. Originator: Neilson, R. P. Originator: Phillips, D. L. Publication_Date: 1994 Title: A statistical-topographic model for mapping climatological precipitation over mountainous terrain Series_Information: Series_Name: Journal of Applied Meteorology Issue_Identification: 33 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1994 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Daly and others (1994) Source_Contribution: p. 40-158 Source_Information: Source_Citation: Citation_Information: Originator: Eimers, J. L. Originator: Weaver, J. C. Originator: Terziotti, S. Originator: Midgette, R. W. Publication_Date: 2000 Title: Methods of rating unsaturated zone and watershed characteristics of public water supplies in North Carolina Series_Information: Series_Name: U. S. Geological Survey Water-Resources Investigations Report Issue_Identification: WRIR-99-4283 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2000 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Eimers and others (2000) Source_Contribution: methods Process_Step: Process_Description: Created a 30-meter Grid data set of NC and adjacent states by resampling the 1971-2000 800 meter grid Process_Date: 2009 Process_Step: Process_Description: Created a grid of each of the years 2001 through 2007 Process_Date: 2009 Process_Step: Process_Description: Create a mean grid of all years of data to get the average annual precipitation amounts from 1971 - 2007 Process_Date: 2009 Process_Step: Process_Description: Used the following remap table to change the classes to a rating from 1 to 10. (Using the Arc/Info GRID command, SLICE, with the TABLE option). >40 : 1 >45 : 2 >50 : 3 >55 : 4 >60 : 5 >65 : 6 >70 : 7 >75 : 8 >80 : 9 >120 : 10 > Process_Date: 2009 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Grid Cell Row_Count: 16160 Column_Count: 28318 Vertical_Count: 1 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: State Plane Coordinate System 1983 State_Plane_Coordinate_System: SPCS_Zone_Identifier: 3200 Lambert_Conformal_Conic: Standard_Parallel: 34.333333 Standard_Parallel: 36.166667 Longitude_of_Central_Meridian: -79.000000 Latitude_of_Projection_Origin: 33.750000 False_Easting: 609601.220000 False_Northing: 0.000000 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: row and column Coordinate_Representation: Abscissa_Resolution: 30.000000 Ordinate_Resolution: 30.000000 Planar_Distance_Units: meters Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1983 Ellipsoid_Name: Geodetic Reference System 80 Semi-major_Axis: 6378137.000000 Denominator_of_Flattening_Ratio: 298.257222 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: precipsw.vat Attribute: Attribute_Label: Rowid Attribute_Definition: Internal feature number. Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated. Attribute: Attribute_Label: VALUE Attribute: Attribute_Label: COUNT Overview_Description: Entity_and_Attribute_Overview: > >Value attribute table, PRECIPSW.VAT: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 VALUE 4 10 B - > 5 COUNT 4 10 B - > 9 PCT_TOT 4 8 F 2 > 13 SQMI 4 8 F 2 > VALUE is rating: valid values are integers between 1 and 10, inclusive. COUNT is the number of 30-meter by 30-meter cells in the entire data set that have the rating. PCT_TOT is the percent of the total area just within NC for each category. SQMI is the conversion from 30 meter by 30 meter cells to square miles for just the NC portion of the study area. > >VALUE COUNT PCT_TOT SQMI > 1 3938485 0.60 320.77 > 2 173700622 38.83 20891.04 > 3 117104416 31.84 17131.79 > 4 52465471 18.51 9958.23 > 5 17335475 6.61 3555.14 > 6 5078301 1.17 626.98 > 7 3105866 0.80 431.70 > 8 1371126 0.42 224.21 > 9 880806 0.44 238.06 > 10 771423 0.48 259.11 > >Summary Statistics Table, PRECIPSW.STA: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 MIN 8 15 F 3 > 9 MAX 8 15 F 3 > 17 MEAN 8 15 F 3 > 25 STDV 8 15 F 3 > MIN is the minimum value of item VALUE. MAX is the maximum value of item VALUE. MEAN is the average value of item VALUE. STDV is the standard deviation of item VALUE. > > MIN MAX MEAN STDV > 1.000 10.000 2.869 1.158 > Entity_and_Attribute_Detail_Citation: none Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Position: Information Officer Contact_Address: Address_Type: mailing and physical address Address: 3916 Sunset Ridge Rd. City: Raleigh State_or_Province: NC Postal_Code: 27607 Country: USA Contact_Voice_Telephone: (919) 571-4000 Contact_Electronic_Mail_Address: gs-w-ncrlg_www@usgs.gov Contact_Instructions: Contact via email Resource_Description: Downloadable Data Distribution_Liability: Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of this data, software, or related materials. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Transfer_Size: 7.539 Metadata_Reference_Information: Metadata_Date: 20090702 Metadata_Review_Date: 2001 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: North Carolina Water Science Center Director Contact_Position: Director Contact_Address: Address_Type: mailing and physical address Address: 3916 Sunset Ridge Road City: Raleigh State_or_Province: NC Postal_Code: 27607 Country: USA Contact_Voice_Telephone: (919) 571-4000 Contact_Facsimile_Telephone: (919) 571-4041 Contact_Electronic_Mail_Address: dc_nc@usgs.gov Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Time_Convention: local time Metadata_Access_Constraints: none Metadata_Use_Constraints: none Metadata_Extensions: Online_Linkage: http://www.esri.com/metadata/esriprof80.html Profile_Name: ESRI Metadata Profile