05-14-2014 Council Agenda - Laserfiche WebLink

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type to establish. Communities that have chosen the part-time zone reasoned that risks associated with no train homs were greatly reduced at night because of the decreased traffic volumes. The FRA has incorporated flexibility in the process to create quiet zones, but has also made the process complex. The concept utilizes a risk index approach that estimates expected safety outcomes. Risk is averaged over the railroad crossings in the proposed zone and compared to a national risk level called the National Significant Risk Threshold (NSRT). This risk analysis computes a Risk Index With Horns (RIWH) and a Quiet Zone Risk Index (QZRI). This analysis determines what crossing improvements are needed for a community to establish a quiet zone. At a minimum, all new quiet zones must have railroad signals with gates. The FRA has provided an Internet site (www.fra.dot.gov) to allow for the calculation of the QZRI and RIWH and NSRT. This is commonly called the Quiet Zone Calculator. There are different ways that a community can institute a quiet zone, and they are based on the risk index approach. Each method may require the community to apply for different types of quiet zones. • A community can install supplemental safety measures (SSM) at each crossing. This would allow for automatic approval from the FRA. • If SSMs are impractical at every crossing, a risk analysis is calculated and if the RIWH is less than the NSRT, or if the QZRI is less than the RIWH, a quiet zone can be instituted without additional safety measures. • If the risk index cannot meet the FRA standards, the City can propose an Altemative Safety Measure (ASM) that the FRA will evaluate on an individual case basis. There are five predetermined engineering improvements, called supplementary safety measures (SSM) that can be used to lower the OZRI and bring a crossing(s) into automatic conformance with the rules. The five SSMs include the following: 1. One -Way Streets with Full Gate Coverage — One -way streets allow for the gate(s) to be placed on the approach lanes of traffic, and vehicles cannot go around the gates. Vehicles also cannot get trapped between the gates. 2. Nighttime Closure of a Crossing — The roadway would be closed by the use of some type of barricade(s) that can completely close off the crossing. This would be used only if a part-time quiet zone is requested. The closure must Include a process that will verify that a crossing has been closed for the night. Other cities have used an automatic barricade that is locked into place and provides a warning light to the train that the crossing is closed. 3. Permanent Closure of the Crossing — This means that the roadway would be closed and barricaded permanently. The railroad signals and surface would be removed. Under the FRA risk computations, the closure allows a credit in the risk assessment that may allow other options at the remaining crossings in the zone. 4. Raised Center Medians — Raised center medians a minimum of 60 feet long (100 feet long preferred) are installed to prevent vehicles from driving around the gates. If the median is less than 6 inches tall, traffic delineators are required. If a roadway is of sufficient width, medians are relatively inexpensive to install. The disadvantage of medians is disruption to local access. 5. Four Quadrant Gates — Four quadrant gates are regular railroad gates with two additional gates being added to the exit traffic lanes. This will completely close off the crossing. The exit gates are on a delay that will allow a vehicle to clear the crossing before descending. LITTC 126672 Page 4 9 Railroad Quiet Zone Report City of Little Canada