Land Use Policy Programmatic Update Goes on the Road Again

Overall the CAO’s office, Planning Department and Department of Transportation (DOT) staff have all been tireless in taking complex matters to public forums, where they’ve been patient and helpful in addressing concerns. LUPPU staff is constantly improving communication efforts both verbally, technologically and visually via the LUPPU website at: http://www.edcgov.us/landuseupdate/

Part of the LUPPU educational process is interactive, and recently a new and unique tool became available to help the public to better understand local land use regulations on individual parcels. Staff is available at the public meetings with internet support by which they can submit property owners’ name and location and produce an instant print-out showing the land use(s) and zoning information specific to the parcel, including specific regulatory changes proposed.

TRAVEL DEMAND MODELING

Given that the LUPPU process in total has been repeatedly described as “complex” its various components are not. The General Plan is relatively simple though time consuming to read. It sets forth long range planning Goals for El Dorado County in a text format for the most part, totaling about 400 pages. It is divided into “elements” or chapters that address a variety of topics from land use and economic strategies to public safety. Transportation and traffic issues are contained in the General Plan’s Transportation Element. As in all GP elements the section contains adopted Goals, along with Objectives and Policies for achieving the goals.

The Zoning Ordinance Update (ZOU), also part of the LUPPU process, is more challenging to many of us. It often requires that people read through it one time to understand the basic document, how it works, and how it’s laid out. It may take additional reading to cross-check specific Articles (chapters) to understand the interaction with other Articles, and to clarify the meaning of EDC zoning terms. The last but not least important Article is the Glossary. Since most words have numerous meanings, the ZO Glossary describes the specific meaning used within the ZO. Reading the GP Transportation Element provides insight into EDC’s defined Goals and Objectives for local traffic, but it won’t necessarily provide information about how the traffic evaluation process is undertaken. Likewise, reading the Zoning Ordinance will help one discern the level of sensitivity EDC has adopted regarding specific uses within specific zones, but it won’t clarify how traffic issues address future impacts.

It’s this writers’ belief that neither the GP nor ZO will provide full clarity about all the interrelationships of local transportation planning. Since so many experts in transportation issues are traffic engineers or traffic planners (who seem to speak an entirely different language than do the rest of us), consultants are key to making traffic-planning processes make sense. EDC was wise to contract with the transportation-consulting firm Kimley-Horn and Associates, Inc. to assist in the LUPPU process, which includes transportation as a third rail (e.g.: the GP and ZOU being the first two rails). The following information is taken from recent presentations Kimley-Horn and Associates, Inc. has conducted as they move forward in updating local transportation planning efforts.

A few years ago DOT was informed of the county’s efforts to perform the required 5-year update of its General Plan (GP), and bring its archaic Zoning Ordinance into consistency with the GP. Historically EDC had left transportation “modeling” to outside consultants. Traffic experts were engaged and would control the modeling on an as-needed contract basis, which allowed little local control over timing and costs. This system has changed with the needs presented by the LUPPU process. The county’s current goal is to update our system technology so that DOT has more control over planning and operating its own Travel Demand Model (TDM) in-house.

LUPPU: TRANSPORTATION UPDATE 

 BOS approval to update local capabilities to model traffic for planning purposes and was included as part of the LUPPU process.
 According to George E.P. Box, “Essentially all models are wrong, but some are useful”, which understates the obvious in this case. Models are only as good as the assumptions used to set the stage for any analysis the model must perform. In the case of traffic modeling, land use forecasting is an intricate part of the formula.

 DOT recognized their inability to accurately track/forecast traffic patterns and solutions, due to outdated technology in use, developed in 1998. Interaction with surrounding jurisdictions is essential as traffic isn’t all moving only within EDC boundaries. Local traffic flow is often impacted by surrounding areas traffic flows. The BOS learned that superior software packages were available and authorized DOT to update the system to a more universally superior technology.

 With Supervisors onboard, DOT began working with the traffic consultants to update local technological systems and create an overall program to better manage transportation planning locally. For example, the new modeling program will extend the planning horizon (currently to 2025) to 2035, keeping in line with General Plan’s assumptions. Development patterns have also changed significantly and EDC can now review and incorporate ten years of realworld data under the current GP, compared to earlier efforts that relied on “forecasts” (educated guesses) of what development patterns would be under the 2005 GP. These patterns are significant because the GP vision is to encourage and plan for higher-intensity development within designated areas such as Community Regions (CR) and Rural Centers (RC). This type of land-use planning is also required by new state laws and mandates.
 The first step in updating local transportation efforts is the use of a Travel Demand Model (TDM). Travel Demand Modeling is a tool for understanding human behavior: Where are people going? Why are they going there? How are they getting where they are going? The TDM can forecast trips (traffic is counted based on “average daily trips” that people take) onto existing and/or projected transportation facilities (e.g.: roads, freeways, highways, etc). Thus the TDM is an essential part of the planning process.

 Another shortfall of EDC’s older model was its inability to maximize the use of GIS information. The new model will coordinate existing roadway network data which contains information such as the number of lanes, stop signs, signals, etc., which has been translated into GIS information.
 Though oversimplified, the basics of Travel Demand Modeling are assumptions and application. Assumptions are based on people, residents, jobs and the trips they generate, for 20-30 years out. TDMs estimate the demands of local people and then test various system improvement scenarios via traffic modeling. Typically the primary use of the TDM is to forecast future travel. The system is sophisticated and involves complex mathematics generally used throughout the United States.

 Travel Demand Modeling can be at either a macro or micro level. The macro model is a big picture tool with information that can be utilized in a micro model. The micro model helps to obtain very specific traffic patterns (i.e. individual car movements). EDC is currently focusing on a macro level. The macro model is a four-step process that considers (1) Where a trip is generated from (e.g.: house, etc), (2) Where the person is going, (3) How individuals are getting there (e.g.: walking, driving, public transport), and (4) What route is being used. The macro process requires consultants to identify major roadway networks and consider land use scenarios/assumptions, including GP land uses and existing development patterns. Land use absorption rates and densities achieved throughout the county are now supported by actual data accumulated under this GP, and are no longer supported solely by theoretical build-out numbers. This brings a higher level of accuracy to local land use predictions and subsequent traffic generated.

 The macro TDM being provided will do a lot, but not everything! It will evaluate road widening and road additions needed, which will improve the Capital Improvement Program (CIP) figures. It can evaluate new interchanges, analyze impacts of transportation plans, and show impacts of large development projects. It can forecast traffic corridor volumes and test alternative land use plans. And, the macro model can be the basis for a micro TDM in the future. A specific macro model is NOT the best model for evaluating new turn lanes at intersections or modeling small or local roads: Both these needs are better served by a micro model. And although the TDMs are not perfect – they ARE the best decision-making tool we currently have for regional travel demand forecasting. So – why aren’t TDMs perfect? TDMs are merely a statistical replication of human behavior that assumes everyone acts rationally. In reality human nature is not always predictable or rational. Human behavior just doesn’t fit into a statistical mold. We can build a forecast model knowing what the existing conditions are and accurately reflecting those, but there will always be external factors that are unknown and out of our control (a road closure, the economy tanks and housing is affected, new roads are not built, even the 9-11 attacks that led to the closure of roads that previously crossed over dams are no longer allowed.)

 Bottom line is that we can make our best assumptions and use statistics where they’re available and relevant, and we can test what we know against existing conditions, and this is what the TDM will do much better than what we’ve had available in the past.