Orestimba Creek Feasibility Study - Stanislaus County

Economics Appendix – Draft Report - Orestimba Creek Feasibility Study, Stanislaus County, California – September 2012
2.2 Inventory of Structures and Property in Study Area
A structural inventory was completed based on data gathered from assessor’s parcel data and onsite
inspection of structures within the flood plain. Structures were determined to be within the
economic study area by using Geographical Information Systems (GIS) to compare the 0.2%
(1/500) ACE flood plain boundary (plus a buffer) with the spatially referenced assessor parcel
numbers (APN). Information from the assessor’s parcel database (such as land use, building
square footage, address) was supplemented during field visitation for each parcel within the
flood plain by adding fields for foundation height, specific business activity (non-residential),
building condition, type of construction, and number of units for example. Windshield survey
field observation conducted on 100% of non-residential structures within 0.2% (1/500) ACE
floodplain. Residential structures were sampled and grouped geographically by areas of
homogeneous characteristics. Where square footage data was not available, the Google Earth
measuring tool was used to estimate square footage. Parcels with structures, were categorized by
land use and grouped into the following structural damage categories:
1) Single Family Residential – includes all parcels represented by a single unit such
as detached single family homes, individually owned condominiums and
townhouses.
2) Multiple Family Residential – includes residential parcels with more than one
unit such as apartment complexes, duplexes and quadplex units. Each parcel may
have multiple structures.
3) Commercial – includes retail, office buildings, restaurants
4) Industrial – includes warehouses, light and heavy manufacturing facilities.
5) Public – includes both public and semi-public uses such as post office, fire dept,
government buildings, schools and churches.
6) Agriculture – Agricultural inventory was developed in a separate analysis.
Please see Attachment B for a detailed writeup of this analysis.
All parcels with structures were assigned to one of the listed categories. Some parcels have more
than one physical structure and some structures, such as condominiums, are represented by
multiple parcels. Table 2-1 displays the total number of structures within the 0.2% (1/500) ACE
floodplain by category. Single family and Multi-family have been grouped together as
“Residential” for presentation purposes.
Table 2-1: Structural Inventory
Number of Units within the 0.2% (1/500) Annual Chance Floodplain by Land Use
Economic
Impact Area
Residential Commercial Industrial Public Total
Rural 158 0 0 0 158
Urban 1122 62 16 7 1207
TOTAL 1,280 62 16 7 1365
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