Orestimba Creek Feasibility Study - Stanislaus County

Economics Appendix – Draft Report - Orestimba Creek Feasibility Study, Stanislaus County, California – September 2012
Executive Summary – Economics – Orestimba Creek Feasibility Study
ES.1
Overview
The study area is located in the southwestern portion of Stanislaus County, in what is referred to
as the Newman Division by the U.S. Census Bureau (see Figure 1). Orestimba Creek stretches
approximately 7.5 within the study after having left the foothills of the Diablo Mountain Range.
It is estimated that in the 500-year flood event the floodplain would encompass approximately
20,000 acres, including the City of Newman (see Error! Reference source not found.). The
City of Newman is the home of approximately 12,321 residents (2010 Census data). The study
area is home to some of California’s most efficient and important agricultural industries.
Tomato and vegetable processing, cheese manufacturing, and turkey hatching are examples of
some of the agricultural industries located in the area. The area is acknowledged for crop
diversity and productivity, which can be accredited to a combination of exceptional factors such
as, soil quality, air quality, climate, and water supply.
The city of Newman has experienced 14 floods in the past 58 years (1954, 1955, 1957-1959,
1963, 1968, 1969, 1978, 1980, 1983, 1986, 1995 and 1998). The major floods occurred in 6 out
of the last 14 flooding events (1955, 1958, 1963, 1980, 1983, 1995 and 1998), with 1995 being
the flood of record. These floods occurred along Orestimba Creek and affected both rural and
urban land uses. The frequency of flooding in and around Newman is similar that which occurs
on an average cycle of between 4 to 5 years. These flooding events have affected the same
general areas each time except when there was a levee failure or similar occurrence that changed
the location of flooding and the type of land uses that were adversely affected.
ES.2
Purpose and Scope of Economic Analysis
The purpose of this report is to present the results of the economic analysis performed for the
Feasibility Study of the Orestimba Creek Project. The report documents the existing condition
within the study area and proposed alternative plans to improve flood risk management, and
designate the National Economic Development (NED) Plan for purposes of estimating federal
interest for Orestimba Creek. The report presents findings related to flood risk, potential flood
damages and potential flood damage reduction benefits.
This Economic Appendix is intended to:
• Document the current hydrologic data used in the economic analysis for the Orestimba
study area under both the without-project and with-project conditions
• Document the current hydraulic floodplains and HEC-FDA hydraulic input data used in
the economic analysis for the Orestimba under both the without-project and with-project
conditions
ES-i