Winter Service Plan 2008-9 (Abridged Version)
5.0 What do we provide?
5.1 The code recognises three principal activities in the service:
- Pre-treatment – “precautionary” salting. Scottish Borders Council uses the term “Priority Treatment” instead. This term is used because on the A708, B6357, B6399, B709, B6358, C27, D66/3, D67/3, C41, C30, C38 roads and some streets in Jedburgh the treatments are carried out only in the morning prior to the anticipated morning traffic. On the other Priority Treatment routes pre-treatment is undertaken.
- Post-treatment – salting of lingering ice
- Clearance of snow
5.2 The financial constraints relating to the service provision can be applied to the above activities to determine the actual standard of the service. The establishment charge for providing the operational resources (depots, plant and staff and management overheads) is termed “Basic Facility and Standby”. Winter costs are a summation of this and actual hours of work in the above three activities.
5.3 Experience shows that the main area that can be subjected to planned financial control is pre-treatment. The standard of ice and snow clearance is dictated by stakeholder expectation and is not usually subjected to financial restraint. In exceptional circumstances the Council’s available plant and staff resources may be augmented by the use of external contractors including farmers.
5.4 The overall standard for Winter Service is thus established as a direct consequence of determining the extent of coverage of priority treatment routes. The code recommends wide publicity of “treated” network, thus establishing that it is only pre-treatment that can be subjected to predetermined alteration.
5.5 The code suggests the minimum spread rates of salt (sodium chloride) for different operational scenarios shown in Table H2.
| Weather Conditions, Road Surface Conditions and Road Surface Temperature (RST) | Air Temperature | Salting (g/m²) | Ploughing |
|---|---|---|---|
| Frost or forecast frost. RST at or above -2º C | 10 | No | |
| Frost or forecast frost. RST below -2º C and above -5º C | 20 | No | |
| Frost or forecast frost. RST below -5º C and above -10º C and dry or damp road conditions | 20 | No | |
| Frost or forecast frost. RST below -5º C and above -10º C and wet road conditions (existing or anticipated) | 2 times 20 | No | |
| Light snow forecast (<10mm) | 20 | No | |
| Medium / heavy snow forecast | 2 times 20 | No | |
| Ice formed (minor accumulations) | above minus 5 degC | 20 | No |
| Ice formed | at or below minus 5 degC | 2 times 20 | No |
| Snow covering exceeding 30mm | 20 to 40 (successive) | Yes | |
| Hard packed snow or ice | above minus 8 degC | 20 to 40 (successive) | No |
| Hard packed snow or ice | at or below minus 8 degC | Salt or Abrasive (successive) | No |
Rate of spread for precautionary treatments may be adjusted to take account of residual salt or surface moisture
New surfacing materials, including thin surfacings, multiple surface dressings, micro surfacings and porous asphalt, exhibit different texture, drainage and thermal characteristics, and may require modifications in winter service practice. Research is continuing into the implications of this. Generally this may imply increased salting on areas of such materials where problems have been experienced.
Unified Solutions.