Chip Seal Map (PDF) (JPG)

The purpose of a chip seal is to prevent corrosion and provide a moisture barrier to existing and new asphalt.  The first step in chip sealing is to clean the street of any debris and patch any holes or cracks. The next step is to apply hot liquid asphalt emulsion on the street. The temperature of this oil is between 140 and 180 degrees. The third step is to apply the 3/8" washed aggregate (chips) as quickly as possible over the hot oil. Rubber-tire rollers are then used to set the rock into the fresh oil. The last step of the chip seal process is to sweep the street to remove surplus chips.  The sweeping process may take up to three weeks to complete.

The purpose of the crack seal operation is to seal cracks in asphalt streets to prevent deterioration of the street by water infiltration.  Crack sealing involves spraying a CRF emulsion directly into and around the crack in a street and blotting with masonry sand when curing has begun.  Work will be performed within designated, properly signed work zones on streets assigned by the supervisor. 

Dirt street grading is to provide a smooth driving surface that is shaped to accommodate traffic, run-off, and slope limitations within City of Helena right-of-way.

There are several factors, which determine methods of maintaining City dirt streets.  They are: slope, traffic, and historical placement within City right-of-way. Dirt streets are generally bladed twice a year, in May/June and October/November.  The Street Division's objective is to maximize the useful life of the roadway and provide the best driving surface for the longest duration under all conditions. To accomplish this, several general principles have been adopted: the steeper the slope the heavier the material used (pit run versus ¾ road mix); the heavier the load the heavier the material (pit run with large rock for heavy truck traffic); the more traffic volume the heavier the material (more traffic volume requires a pit run base); a crown or cross slope of at least 4% shall be placed on the surface to keep water from the driving surface and into ditches or gutters; culverts are encouraged for access approaches where necessary .

Potholing is a repair to an asphalt surface that has broken and/or eroded to a point that a hole or cavity exists.  Potholing is executed to minimize damage to vehicles, prevent falls, and preserve the surrounding area. 

Potholing can be divided into three distinct activities.  Temporary repairs with cold mix, long term repairs hot mix, and skin patching to cover wide areas of decay or settlement and wide crack coverage. This activity is conducted in active traffic. Visibility and awareness is of extreme importance.

To report a pot hole contact:
Laurie Miller - 447-1566
lmiller@ci.helena.mt.us

The purpose of sweeping is to keep the city asphalt streets free of dirt and debris.  The Street Division will do its best to help the city present a positive image.  Clean streets are very important in achieving that end.  Control of dirt and dust is also important in maintaining air quality.

The Street Division employs a variety of sweeper types to maintain the streets for a variety of conditions:  wet and heavy sand and/or sediment following downpours or spring thaw; dry debris and dust of summer; heavy chips following chip and seal operations; leaf pickup in the fall; and dry and cold pickup in the winter.  Sweeping is a maintenance operation and by definition we will never finish.  Our operation slowly, methodically, and with persistence will sweep our streets to maintain a clean appearance.

The public can do several things to assist the Street Division in efforts to keep our beautiful city clean and presentable.  The first and most important would be to move vehicles and trailers parked along the curb periodically.  This allows sweeper access to all curb lines.  Vehicles that are unusable should be moved off street to comply with the City of Helena Abandoned Vehicle Ordinance.” If it is inconvenient to move, broom the area so a sweeper can pick up the debris.  Sweep winter sand from sidewalks into the gutter during spring cleanup.

The Street Division is able to recover leaves that fall onto the street and boulevard and adjacent sidewalks   We will not sweep leaves that come from lawns, as we do not have the resources to accommodate this volume of debris.  Please bag or haul leaves to the Transfer Station. 

For safety reasons please do not leave portable basketball hoops in the street.  They are difficult to see and navigate around and can damage our equipment, which could result in the pursuit of repair costs.

Alley grading is done to shape the surface within the city right of way to desired specifications.  Alleys are maintained to accommodate access to properties, garbage pick-up, and runoff.  Several factors influence grading and maintaining alleys including access from streets, right of way width and location, adjoining properties and their structures, slope(s), utilities, and parent material.

The Street Division has embarked upon a program of concentrated grading within neighborhoods that address recurring problems in alleys.  Our objective is fourfold;  1) provide a cross-slope that channels runoff onto one side of the alley that minimizes flooding onto lower elevation properties; 2) provide a uniform slope(s) to adjacent streets wherever possible; 3) provide adequate access to adjacent properties where possible; 4) provide a smooth durable surface within physical limitations.

Property owners are responsible for keeping alleyways clear of debris and overgrowth of trees and shrubs to allow for garbage pick-up and alley maintenance.