Attribute_Accuracy:
Attribute_Accuracy_Report: The method for estimating the number of onsite wastewater
management systems in the watershed involved first determining
both the location of all residential structures and the extent
of existing sewer districts, then identifying all the
residential structures not located within the boundary of the
sewer districts, assuming these residential structures would
require onsite wastewater management systems. Though this method
may not be precise, it is expected to provide reasonable and
sufficient accuracy for estimating non-point source pollution at
the scale of the watershed or subwatershed using the GWLF model.
U.S. Census block-level data was used to estimate the number of
residents per residential structure. The product of this effort
was a single geospatial data layer indicating the location of
all residential structures with onsite wastewater management
systems and the estimated number of individuals using those
systems. It is important to note that these numbers and
locations are estimates and not precise measurements.
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: NYS Cyber Security and Critical Infrastructure
Coordination
Publication_Date: 2003 and 2004
Title: Cayuga, Cortland, Schuyler, Seneca, Tioga, and
Tompkins County Orthoimagery
Geospatial_Data_Presentation_Form: remote-sensing image
Series_Information:
Series_Name: NYS Digital Orthoimagery Program (NYSDOP)
Issue_Identification: 2002 and 2003
Type_of_Source_Media: online
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 2002
Ending_Date: 2003
Source_Currentness_Reference: ground condition
Source_Citation_Abbreviation: NYSDOP
Source_Contribution: High-resolution aerial imagery used to identify
inhabitable structures.
Source_Information:
Source_Citation:
Citation_Information:
Originator: Tompkins County ITS GIS Division
Originator: Hitachi Software
Publication_Date: 20051005
Title: Tompkins County Building Outlines
Geospatial_Data_Presentation_Form: vector digital data
Publication_Information:
Publication_Place: Tompkins County, NY
Publisher: Tompkins County ITS GIS Division
Other_Citation_Details: Derived from 2002 Tompkins County orthoimagery
provided by NYS Office of Cyber Security &
Critical Infrastructure Coordination
Type_of_Source_Media: online
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2002
Source_Currentness_Reference: ground condition
Source_Citation_Abbreviation: TOMPKINS BUILDINGS
Source_Contribution: Locations of structures within Tompkins
County.
Source_Information:
Source_Citation:
Citation_Information:
Originator: Cayuga Lake Watershed Network
Originator: Nicholas Hollingshead, GIS Analyst
Publication_Date: 20060901
Title: Land Use and Land Cover in the Cayuga Lake
Watershed
Geospatial_Data_Presentation_Form: vector digital data
Type_of_Source_Media: online
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 2002
Ending_Date: 2004
Source_Currentness_Reference: ground condition
Source_Citation_Abbreviation: LAND USE
Source_Contribution: Used to classify structures as residential or
non-residential.
Source_Information:
Source_Citation:
Citation_Information:
Originator: Cayuga Lake Watershed Network
Originator: Nicholas Hollingshead, GIS Analyst
Publication_Date: 20070901
Title: Sewer Systems Extent in the Cayuga Lake Watershed
Geospatial_Data_Presentation_Form: vector digital data
Type_of_Source_Media: online
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2007
Source_Currentness_Reference: ground condition
Source_Citation_Abbreviation: SEWER EXTENT
Source_Contribution: Areas served by municipal sewer systems.
Source_Information:
Source_Citation:
Citation_Information:
Originator: U.S. Department of Commerce, U.S. Census Bureau,
Geography Division
Publication_Date: 2001
Title: TIGER/Line Files, Census 2000
Geospatial_Data_Presentation_Form: vector digital data
Type_of_Source_Media: online
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2000
Source_Currentness_Reference: ground condition
Source_Citation_Abbreviation: CENSUS 2000
Source_Contribution: Population data for Census blocks, used to estimate
the number of residents per inhabitable
structure.
Process_Step:
Process_Description: Map location of all structures in the Cayuga Lake
watershed: During the first phase of the study, the
locations of all inhabitable structures were identified
using aerial imagery acquired from the NYSDOP for Cayuga,
Cortland, Schuyler, Seneca, Tioga, and Tompkins counties.
The imagery was captured in 2002 and 2003 in "leaf-off"
conditions. The types of structures mapped included houses,
mobile homes, apartment buildings, commercial buildings,
government-owned buildings, churches, etc. The dataset did
not include storage structures such as sheds or barns.
Source_Used_Citation_Abbreviation: NYSDOP
Source_Used_Citation_Abbreviation: TOMPKINS BUILDINGS
Process_Date: unknown
Process_Step:
Process_Description: Classify structures as residential or non-residential:
Each inhabitable structure was classified as residential or
non-residential. The classification of each structure was
based on the land use and cover type of the area in which it
was located. The land use and cover geospatial dataset used
to determine a structure's class was developed in the first
phase of the development of the CLW GWLF GIS.
Source_Used_Citation_Abbreviation: LAND USE
Process_Date: unknown
Process_Step:
Process_Description: Identify residential structures within the extent of
the municipal sewer systems: Detailed information about
which structures were connected to municipal sewer systems
and which required on-site waste management systems was not
available. Therefore, the simplest assumption, that all
residential structures within a reasonable distance, 150
feet, of a sewer line are connected to that sewer system was
chosen. Although this assumption might not be accurate in
all cases, it should hold true in the majority of cases. All
residential structures that met this assumption were
classified as being on a municipal sewer line and therefore
not having an on-site waste management system. All
residential structures not identified as being on a
municipal sewer system were classified as having on-site
(septic) waste management systems.
Source_Used_Citation_Abbreviation: SEWER EXTENT
Process_Date: unknown
Process_Step:
Process_Description: Estimate number of residents per residential
structure: To develop an estimate of the number of
individual residents using each on-site waste management
system, the total number of residents within each census
block was divided among the residential structures located
within that census block.
Source_Used_Citation_Abbreviation: CENSUS 2000
Process_Date: unknown
