Planning Services

Transportation Impact Studies (TIS) are one of the tools used to provide information for implementation of the Transportation and Circulation Element of the County’s General Plan. A TIS helps the County evaluate the potential effects of proposed projects on transportation infrastructure and services and determine how identified impacts can be mitigated. A TIS should be a stand-alone document that can be reproduced by a peer consultant or County staff based on information provided in the document. It is not a persuasive document; it is a factual document utilizing state of the practice and industry technical analyses.

TIS guidelines are routinely established by jurisdictions to assist applicants with assessing potential traffic impacts of proposed projects in accordance with the jurisdiction’s adopted policies and plans. In 2008, the El Dorado County Department of Transportation (DOT) produced the Traffic Impact Study Protocols and Procedures (2008 TIS Protocols). The 2008 TIS Protocols were created to help standardize the format and methodology used in traffic impact studies submitted with new development projects. The 2008 TIS Protocols were considered a technical internal document created and maintained by DOT to implement adopted Board policy.

In 2014, the 2008 TIS Protocols were revised. The updated version is titled “Transportation Impact Study (TIS) Guidelines” to acknowledge the analysis will require study of all modes of transportation, not just motorized vehicles. The TIS Guidelines include an outline of the expected format, citations from state law and El Dorado County General Plan policies, as well as appendices with applicable information.

The updated TIS Guidelines will assist applicants in the preparation of TIS for proposed projects within unincorporated areas of El Dorado County. These guidelines are intended to ensure that the traffic impacts of proposed development projects are addressed in a manner consistent with the policies set forth in the Transportation and Circulation Element of the County’s General Plan and any applicable Specific Plan. The guidelines also enable the County to analyze the potential transportation and circulation impacts of development proposals pursuant to the requirements of the California Environmental Quality Act (CEQA). The County expects these guidelines to result in studies that provide comprehensive and accurate analysis of potential transportation impacts to County facilities and services. In December 2014, the updated TIS Guidelines document was presented to the Board of Supervisors.