How to write a snow plan for a parking lot

What is a parking lot snow plan?

It is the written record of how a specific lot will be handled in winter. The Snow & Ice Management Association (SIMA) separates the idea into a few documents. A site map is the visual map used for bidding. A site engineering plan is the contractor's version, used to guide crews. A site plan, in the standard SIMA-10-2025, is the documented plan of action covering hazards, priorities, timing, what starts service, and who watches the site.

For a small lot these can all live on one sheet. What matters is that the decisions exist in writing. SIMA-10 says signed contracts should define the level of service, the scope of work and the site plan, so the plan should be attached to the contract or referenced by it, not left in someone's truck.

What should the site map show?

SIMA-10 says the map should at minimum show accurate property boundaries, the areas to be serviced, areas approved for stacking, high-priority areas, and locations for salt bins and equipment staging. It also recommends a grid, so that a note can refer to a specific block of the lot rather than "the far corner by the fence".

Start from an aerial image or an existing site drawing and walk it with a pen. Mark property lines carefully where a lot meets a neighbor, because snow pushed over a line becomes someone else's problem, and SIMA-10 asks the scope to note shared lots and adjacent properties. Add door locations, accessible stalls, hydrants, drains, light poles, curbs and islands. Date the map, and reissue it whenever something changes.

Which areas should be cleared first?

The standard's priority list is a good starting point: site entrances and exits for emergency responder access, sidewalks, building entrances and exits, accessible parking stalls and delivery ramps. It adds surfaces that need extra attention for safety and public access, such as hydrants and emergency exits. Number them on the map. After that come the main drive lanes, then the stall rows nearest the building, then outlying rows and edges.

Our own commercial snow and ice management accounts follow the same logic: entrances, accessible parking and main pedestrian routes first, then the rest of the lot, then the edges. Your site may need a different order, such as a loading dock before anything else, and the plan is the place to say so.

Where should the snow be stacked?

In places that will not create the next problem. Rule out anything that blocks sightlines at exits, buries accessible stalls, covers hydrants or sits uphill of a walkway. Melt runs downhill and refreezes after dark, so a pile above an entrance can create ice on a day with no snowfall. Prefer corners that drain away from foot traffic, and landscaped islands only if you accept the effect on the plants. Our guides to where to pile snow and de-icing salt damage go deeper.

Also plan for the volume. Each stacking area takes parking spaces out of use, so count the stalls you can afford to lose and say when the plan shifts from stacking to relocation or hauling. SIMA's glossary keeps those separate: relocation moves snow within the site, while removal takes it away. Name who can approve hauling, because that decision tends to come up late in a long storm.

Does snow storage affect drainage and groundwater?

It can. Most of Missoula's stormwater reaches the aquifer through what the City describes as more than 6,000 dry wells, also known as sumps. Montana sites should check local requirements with the City, county or state. For an example of what a regulator asks for, Connecticut's environmental agency says snow should go in upland areas where sand and debris can be collected after melt, and not within 100 feet of drinking water wells, in wetlands, on storm drain catch basins or drainage swales, or on sloped stream banks. That is another state's guidance, not Montana law, but it is a sensible checklist.

SIMA-10 asks the site assessment to record proximity to rivers, streams, lakes and wells, plus any local or state rules. On the map, mark every inlet and sump, and keep piles off them. A blocked inlet also leaves meltwater with nowhere to go except across the pavement, where it freezes overnight.

What obstacles belong on the plan?

SIMA-10 lists cart corrals, dumpsters, islands, bollards, speed bumps and parked vehicles as examples of obstacles to identify, and its preseason inspection also calls out broken curbs, potholes, car stops, and leftovers such as the stubs of removed signs or bollards. Anything low disappears under the first snowfall. Mark it on the map and stake it on the ground before the ground freezes. Our guide to snow stakes and markers explains placement, and SIMA-10 says the contract should state who installs and removes the stakes.

Repair what you can before winter. The standard makes it the owner's job to fix hazards identified in the preseason inspection. A pothole filled in October will not catch a plow edge in January, or hold a puddle that turns into a patch of ice.

Where will ice form on your lot?

Mostly in the same places every year. SIMA-10 points to slopes and drainage problems, awnings and overhangs, clogged downspouts, and water directed into pedestrian areas. To that list add the shaded side of the building and the ground below any snow pile. If you have a chance, look at the lot on a wet afternoon in the fall and see where water sits and runs: those are your hot spots.

The plan should mark them and say who deals with them. Some can be eliminated, for example by extending a downspout. The rest need a protocol, because SIMA-10 asks that conditions which cannot be eliminated get assigned a solution or a responsible person. It also asks the plan to assign site monitoring for ice that forms after a service, including thaw and refreeze from piles. Our guide to black ice explains why those spots turn hazardous after dark.

Does the order of plowing really matter?

Yes, because snow gets harder to move the more it is handled. SIMA's glossary notes that mechanical agitation from wind or plowing accelerates hardening, so the work takes less time and effort if snow is plowed to its final resting place on the first run. It also says compaction can shrink a volume of snow by as much as eight times. That is the practical case for planning push directions and pile locations before the storm, not during it.

Note the push direction on the map for each section, and any spot where a windrow must not be left, such as across an accessible aisle or a fire lane. If cars will still be parked in a row, say what happens to that row and when it gets a return visit.

What timing belongs in the plan?

SIMA-10 asks for the critical times: when the public uses the site, employee arrivals and shift changes, deliveries, when the lot lights come on, and who is watching the site and when. Add the trigger and any completion times, plus what changes in a long or severe storm. Our guides to trigger depth and realistic response times can help you set them.

Who decides what during a storm?

Write down names and numbers. SIMA-10 asks the contract to set out who can start or continue service, add services outside the agreed scope, and stop service, and it asks for a communication plan covering complaints, changes, incidents and damage. Include a backup for each person, because a storm does not wait for someone to come back from vacation. If tenants share the lot, give them one route for complaints, so crews are not taking instructions from whoever walks up to the truck.

When should the plan be written and reviewed?

Earlier than most people do it. SIMA-10 recommends starting the request for proposals no later than May and awarding contracts no later than September 1. If you are reading this in November, do not skip the plan; do a shorter one this week while the pavement is still visible. The standard also calls for a joint inspection within 30 days of the end of a typical winter season, and that is the moment to mark up the plan with what worked, and note any damage. Keep it with your snow service records.

This guide is part of our Montana Winter Property Guide. If you would like help drawing one up, walking a site and agreeing a plan is how we start commercial and HOA snow removal accounts, as part of our snow and 24-hour storm services. Call HJ Property Care & Tree Service at (406) 215-7319 or request a snow proposal and we will walk the site with you before the first storm.

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