HomeMy WebLinkAboutSOP 1 - Winter Road MaintenanceStandard Operating Procedure
Town of Lexington
Department of Public Works
Winter Road Maintenance
Issue Date: June 2020
Revision: 0
Revision Date:
Responsible Parties
Department of Public Works, Superintendent of Highway
Purpose of SOP
Document the Town’s procedures for winter road maintenance, use and storage of salt and sand and proper disposal of snow.
MS4 Permit – Required Level of Service
Evaluate and implement ways to reduce the use of salts and/or use alternative materials in their place. (In the MS4 Permit, “salt” refers to any chloride-containing material used to
treat paved surfaces for deicing, including sodium chloride, calcium chloride, magnesium chloride, and brine solutions.)
Ensure that snow is not disposed into waters of the United States.
Equipment
The Town owns, operates, and maintains the following ice control and snow removal equipment:
8 Salt Spreaders
The Town rents the following ice control and snow removal equipment:
3 Loaders
Materials and Storage
Prior to each winter season, the Town assesses deicing materials, and to the extent practical, selects materials that have the least impact on water quality while still effectively meeting
the Town’s public safety needs for a variety of winter conditions. The Town’s major materials used in snow and ice control are salt brine (manufactured in-house), rock salt, and BioMelt
AG-64 (Sugar Beet, Corn and Soybean Derivative) Brine Enhancer. These materials are stockpiled in tanks and a salt shed at the DPW Facility at 201 Bedford Street. The quantity of these
materials is assessed in advance of a storm event to ensure supply is sufficient. Stocks are replenished between events.
Cover from Precipitation: Solid salt and other chemical deicers are stored in the DPW’s salt shed unless active loading or spreading is occurring. The containment structure is permanent
in its construction and made of materials that are not subject to salt corrosion. Temporary storage of salt and other chemical deicers is not recommended; however, if materials must
be stored outside of a permanent structure, the storage must be on a temporary basis only. Temporary storage piles are covered with a tarp and adequately secured at all times when not
being actively worked.
Impervious Bottom: Salt and other chemical deicers are only stored on an impervious surface such as a concrete slab or an asphalt parking lot. The use of a tarp or other material as
an impervious bottom is not adequate, unless specifically designed and certified by a professional engineer.
Management of Run-on and Run-off: Salt and other deicing materials are stored away from storm drain inlets and other conveyance structures. Storage structures provide adequate barriers
to prevent run-on into the storage pile, runoff from the storage pile and minimize erosion from the pile.
Operations
Weather Forecasts: The Town receives information from ClearPath Weather and monitors multiple local weather forecasts to inform winter operations.
Road Temperature Sensors: Eight spreaders are equipped with road and atmospheric temperature sensors to evaluate road freezing conditions and the timing of anti-icing and deicing activities.
RoadDSS: Road weather station measures all of the pertinent aspects of winter weather including Road Friction. This Decision Support System (DSS) helps decide when to apply chlorides,
only when needed.
Mobilization: Town staff and subcontractors receive mobilization orders prior to storm events to begin anti-icing activities on every Town-owned road and parking lot. Mobilization orders
for plowing occur at the first sign of snow fall.
Automatic Vehicle Location (AVL) System: The Town will implement the use of an AVL system to avoid route redundancies and optimize snow and ice removal efforts in the 2020-2021 winter
season. The AVL system is intended to help Town management understand what is happening on the road to inform operators of any needed changes.
Route Prioritization: The Town maintains a master schedule of snow and salting routes. Every main, sub-main, and residential street will be treated (with salt and/or liquid) and/or plowed.
During a heavier snowfall (2 plus inches), the focus of clearing roadways will be on main streets first, sub-mains second and residential streets third.
Plowing Routes: The Town divided its 46 plow routes and 8 Sidewalk routes into three sections which are assigned to the Highway, Water/Sewer, and the Public Grounds Divisions. DPW is
also responsible for plowing 9 school parking lots, school driveways and 4 Town parking lots. Each route is assigned necessary equipment depending on the amount of snowfall.
Anti-icing: Liquid anti-icing materials (salt brine) are applied prior to storm events (assuming no preceding rain) to prevent the bond between winter precipitation and the road surface
to reduce the amount of deicing material necessary for a storm event.
De-icing: The Town evaluates the timing and extent that deicing materials are applied during and at the end of a storm event based on the post-storm weather and road conditions.
Ground-Speed Controlled Spreaders: Six of the Town’s salt spreaders are automatically controlled by the vehicle’s ground speed to apply the appropriate amount of deicing material and
avoid over-application at low speeds or intersections.
Equipment Calibration: All equipment is calibrated every November in accordance with the manufacturer’s instructions and the specified applications rates for the material being applied.
Application Rate: The Town uses the lowest application rate that will effectively treat surfaces to meet safety needs.
Loading: When loading salt, sand, or other deicers, care is taken to not overfill the truck or tank and spilled material is cleaned up following loading operations.
Snow Pile Placement: The Town has one designated snow pile placement site at 53 Westview Street.
Operations
Weather Forecasts: The Town receives information from ClearPath Weather and monitors multiple local weather forecasts to inform winter operations.
Road Temperature Sensors: Eight spreaders are equipped with road and atmospheric temperature sensors to evaluate road freezing conditions and the timing of anti-icing and deicing activities.
RoadDSS: Road weather station measures all of the pertinent aspects of winter weather including Road Friction. This Decision Support System (DSS) helps decide when to apply chlorides,
only when needed.
Mobilization: Town staff and subcontractors receive mobilization orders prior to storm events to begin anti-icing activities on every Town-owned road and parking lot. Mobilization orders
for plowing occur at the first sign of snow fall.
Automatic Vehicle Location (AVL) System: The Town will implement the use of an AVL system to avoid route redundancies and optimize snow and ice removal efforts in the 2020-2021 winter
season. The AVL system is intended to help Town management understand what is happening on the road to inform operators of any needed changes.
Route Prioritization: The Town maintains a master schedule of snow and salting routes. Every main, sub-main, and residential street will be treated (with salt and/or liquid) and/or plowed.
During a heavier snowfall (2 plus inches), the focus of clearing roadways will be on main streets first, sub-mains second and residential streets third.
Plowing Routes: The Town divided its 46 plow routes and 8 Sidewalk routes into three sections which are assigned to the Highway, Water/Sewer, and the Public Grounds Divisions. DPW is
also responsible for plowing 9 school parking lots, school driveways and 4 Town parking lots. Each route is assigned necessary equipment depending on the amount of snowfall.
Anti-icing: Liquid anti-icing materials (salt brine) are applied prior to storm events (assuming no preceding rain) to prevent the bond between winter precipitation and the road surface
to reduce the amount of deicing material necessary for a storm event.
De-icing: The Town evaluates the timing and extent that deicing materials are applied during and at the end of a storm event based on the post-storm weather and road conditions.
Ground-Speed Controlled Spreaders: Six of the Town’s salt spreaders are automatically controlled by the vehicle’s ground speed to apply the appropriate amount of deicing material and
avoid over-application at low speeds or intersections.
Equipment Calibration: All equipment is calibrated every November in accordance with the manufacturer’s instructions and the specified applications rates for the material being applied.
Application Rate: The Town uses the lowest application rate that will effectively treat surfaces to meet safety needs.
Loading: When loading salt, sand, or other deicers, care is taken to not overfill the truck or tank and spilled material is cleaned up following loading operations.
Snow Pile Placement: The Town has one designated snow pile placement site at 53 Westview Street.
Maintenance
Loading areas are swept frequently to prevent salt build-up and run-off. At a minimum, loading areas are inspected and swept when needed.
Equipment is washed indoors in a wash bay and stored at the DPW Facility.
Record Keeping and Documentation
Copies of manufacturer’s recommendations for equipment calibration, plowing speed, and salt application rates as well as calibration records and documentation of new equipment purchases
is kept at the DPW Facility.
During each winter storm event, the Town documents the volume of deicers loaded into each salt spreader. Following the event, the Town uses this information to determine the total quantity
of materials used throughout the event.
The Town documents the miles of roads plowed or treated, the totals of materials used, and evaluates opportunities to minimize the use of materials and optimize plowing routes annually.
Efforts to reduce chloride-containing materials are reported in the Town’s MS4 annual report.
Training
This SOP is incorporated into annual training for applicable Town staff. Documentation of the trainings, including sign-in sheets and learning materials used, will be included in the
Town’s MS4 annual reports.
Revising the SOP
These procedures are reviewed annually by the DPW and updated as needed.