Preserving Municipal Roads: What Are Your Options?
Fracking wells, windmill farms, biodiesel facilities; there are lots of new businesses that may increase the traffic on local highways. Forest loggers, coal haulers, a new shopping plaza; there are also lots of existing businesses that may, or already have, increased the traffic on local highways. The fundamental question for a highway agency dealing with a possible increase in traffic is What are my options?
Highways form the backbone of moving goods, services, and people from one point to another. Local municipalities in New York State maintain eighty-six percent of all the centerline miles. We rely on these highways on a daily basis to get from here to there. If the road surface is too rough, it will cost more to travel on the highway. Local municipalities have to balance the need for access with the effects of increased traffic. One person’s improved economy is another person’s environmental damage.
Much discussion is currently underway on this last issue because of the Marcellus Shale natural gas exploration and drilling taking place in the Southern Tier and Western Catskills. The drilling process may require over a million gallons of water per well. One estimate of the number of truck trips for a single well site ranges from nearly 900 to over 1,300, with most occurring during a very short period when the wellhead is set up for the first time (figures taken from the New York State Department of Environmental Conservation’s [NYSDEC] draft Generic Environmental Impact Statement [GEIS]). There are some who think the draft GEIS does not do enough to regulate the gas industry. There are many highway agencies in New York State that would not think of the NYSDEC as an agency that is too lenient, but there are always differences of opinion on controversial issues such as this one. The draft GEIS is over 500 pages long, NOT including the glossary, bibliography, and other appendices. Comments on the draft GEIS are due at the end of 2009. If you do not have time to read the entire document, the following three chapters are a quick starting point to at least get the basics:
- Chapter 1 - Introduction, 5 Pages
- Chapter 8 - Permit Process and Regulatory
- Coordination, 10 pages
- Chapter 9 - Alternative Actions, 11 Pages
In upcoming issues of Nuggets & Nibbles, we will examine in more depth the various options available for local agencies when dealing with increased traffic due to ANY development, not just the Marcellus Shale drilling. We may look at truck access laws, access and hauling fees, highway permits, weight restrictions, and evaluation of existing roads along with other possible options for local agencies. Let’s first take a look at why the Marcellus Shale is being explored and the need to have an inventory of your highway system.
Marcellus Shale Drilling
Natural gas shale is a valuable source of energy. Unfortunately, shale is an impervious rock and it can be very difficult to extract any gas held within it. To get gas from the rock, vertical shafts are first drilled down to the layer of shale (typically several thousand feet deep in most of New York State). Directional drilling then creates horizontal shafts inside the shale layer. However, this process alone does not release enough gas to make it economically feasible.
To increase the amount of gas released, the shale is fractured using a process of hydraulic fracturing also know as “fracking” (see Figure 1). Fracking uses water, solids such as sand, and some additional additives to create small fissures in the rock which allow the gas to escape. In addition to the natural gas, some of the water used in the process, along with natural water already in the shale zone, comes back up the hole and has to be treated. Treatment is necessary because of the additives added to make the fracking fluid more effective, and also due to extra contaminants picked up from the shale during the drilling process.
New technological advances, coupled with increased demand and the rising price of natural gas, have made it economically feasible to begin extracting natural gas from so-called ‘tight shales.’ In the case of the Marcellus shale, there is some evidence that the shale may be easier to fracture due to the presence of pyrite (fool’s gold). If so, the amount of gas released may be larger than the typical ten percent of available gas found in most gas shales. If so, this would make the Marcellus shale the largest source of natural gas in the United States. Figure 2 (see below) shows the area and depth of the Marcellus Shale in and around New York State.
For those interested, there is a wealth of information available on the internet discussing the issues involved with drilling of the Marcellus Shale. Cornell Cooperative Extension has developed a website specifically to help provide unbiased information: http://gasleasing.cce.cornell.edu Creating a Highway System Inventory A fundamental starting point for any review of your options is to know where you are today. It is like getting directions from one place to another - knowing where you are going is important, but you have to know where you are starting from. In the case of highways, we need to start with an inventory of what we have. The more information we have at our fingertips, the more confident we can be in choosing an option.
A highway inventory is the process of collecting the information necessary to adequately describe the highways in the local network. The amount and type of information gathered can be adjusted to fit the specific needs of an individual community. The objective is to gather what you need without gathering too much. A good rule of thumb to follow in starting an inventory is “DON’T GET CARRIED AWAY!”
An inventory does not require the use of a computer; manual systems can work very well. The inventory may be as simple as a map showing all roads with notations about section length, width, pavement type, and date of construction or last improvement. There are also any number of computer based systems that can be used. Which system you use depends upon your needs.
Defining Section Boundaries
Before actually starting the inventory, the highway system needs to be divided into manageable sections. Sections are defined so that the critical information about the pavement within their boundaries is consistent in physical characteristics and other factors. It is not necessary that all segments be the same length. Any one of the following would define the boundary between two sections:
- Change in the number of traffic lanes
- Change in pavement type (chip seal to hot-mix, for instance)
- Abrupt change in traffic patterns or volume
- Change in drainage characteristics (such as curb and gutter to a drainage ditch section)
- Change in pavement structure (thickness, material, etc.)
- Boundary between previous construction projects (different projects can reflect differences in design, materials, age, and other factors)
In addition, geographic or man-made features may offer or force section boundaries. Examples include:
- Rivers or streams
- City or town limits
- County lines
- Railroad grade crossings
- Road intersections
Urban streets can be divided easily into sections using intersections or blocks. One important consideration is how to count the area within the intersection. The intersection areas should be carefully defined to avoid duplication. Two common alternatives are to either always include the intersection with the major road or to make the intersection its own segment. If your agency would work on an intersection as a separate project, the last method makes the most sense.
The inventory process can be completed over time, but should be as simple as possible while still collecting the required information. Listed below are types of information that should be considered for collection:
- Section Description - The description includes the name or route number of the road.
- Functional and Administrative Classification - The functional classification of the street or road (arterial, collector and residential) and special designations such as school bus routes should be recorded if this information will be used in priority-setting by your agency.
- Pavement Structure - This includes pavement thickness, type, and materials. In the case of truck traffic, this information can be very useful.
- Roadway Geometry - Geometry refers to the visible features of a road, and includes pavement width, number of lanes, median width, shoulder width and type, and parking locations.
- History - The date of construction, dates and type of successive maintenance such as surface treatments or reconstruction should be recorded if available.
- Traffic - This should include both Average Daily Traffic (ADT) and percent (%) of trucks. See the sidebar in the righthand column of this page for a simple way to estimate daily traffic.
- Drainage Characteristics - This should describe the drainage system for the section, such as storm sewers, side ditches, curb and gutter, and all subsurface drainage.
A complete physical inventory can be very costly and the most time consuming portion of road management plan. Any data not directly related to surface performance, but which may be beneficial to the municipality, can be collected when collecting the basic information listed above. Additional information may include:
- Traffic control devices
- Drainage structures
- Right-of-way width
- Sidewalks and curbs
It is possible to attempt too much during the initial inventory. It may be better to get started with something simple than to collect too much information. In the next issue of Nuggets & Nibbles we will look at how this inventory information can be used to develop a simple pavement management plan. We will also discuss options for local agencies to preserve their roads.