GenerateServiceAreas

Title  GenerateServiceAreas

Summary

Creates network service areas around facilities. A network service area is a region that encompasses all streets that can be accessed within a given distance or travel time from one or more facilities. For instance, the 10-minute service area for a facility includes all the streets that can be reached within 10 minutes from that facility.

Service areas are commonly used to visualize and measure accessibility. For example, a three-minute drive-time polygon around a grocery store can determine which residents can reach the store within three minutes and are thus more likely to shop there.


Usage


Syntax

Parameter Explanation
Facilities

The input locations around which service areas are generated.

You can load up to 1,000 facilities.

The facilities feature set has an associated attribute table. The fields in the attribute table are described below.

ObjectID

The system-managed ID field.

Name

The name of the facility. If the name is not specified, a name is automatically generated at solve time.

All fields from the input facilities are included in the output polygons when the Polygons for Multiple Facilities parameter is set to Overlapping or Not Overlapping. The ObjectID field on the input facilities is transferred to the FacilityOID field on the output polygons.

Breaks

Specify the extent of the service area to be calculated on a per facility basis.

This attribute allows you to specify a different service area break value for each facility. For example, with two facilities, you can generate 5- and 10-minute service area polygons for one facility and 6-, 9-, and 12-minute polygons for the other facility.

Separate multiple break values with a space, and specify the numeric values using the dot character as your decimal separator, even if the locale of your computer defines a different decimal separator. For example, the value 5.5 10 15.5 specifies three break values around a facility.

AdditionalTime

The amount of time spent at the facility, which reduces the extent of the service area calculated for the given facility. The default value is 0.

For example, when calculating service areas that represent fire station response times, AdditionalTime can store the turnout time, which is the time it takes a crew to put on the appropriate protective equipment and exit the fire station, for each fire station. Assume Fire Station 1 has a turnout time of 1 minute and Fire Station 2 has a turnout time of 3 minutes. If a 5-minute service area is calculated for both fire stations, the actual service area for Fire Station 1 is 4 minutes (since 1 of the 5 minutes is required as turnout time). Similarly, Fire Station 2 has a service area of only 2 minutes from the fire station.

AdditionalDistance

The extra distance traveled to reach the facility before the service is calculated. This attribute reduces the extent of the service area calculated for the given facility. The default value is 0.

Generally, the location of a facility, such as a store location, isn't exactly on the street; it is set back somewhat from the road. This attribute value can be used to model the distance between the actual facility location and its location on the street if it is important to include that distance when calculating the service areas for the facility.

AdditionalCost

The extra cost spent at the facility, which reduces the extent of the service area calculated for the given facility. The default value is 0.

Use this attribute value when the travel mode for the analysis uses an impedance attribute that is neither time based nor distance based The units for the attribute values are interpreted to be in unknown units.

CurbApproach

Specifies the direction a vehicle may arrive at and depart from the facility. The field value is specified as one of the following integers (use the numeric code, not the name in parentheses):

  • 0 (Either side of vehicle)—The vehicle can approach and depart the facility in either direction, so a U-turn is allowed at the facility. This setting can be chosen if it is possible and practical for a vehicle to turn around at the facility. This decision may depend on the width of the road and the amount of traffic or whether the facility has a parking lot where vehicles can enter and turn around.
  • 1 (Right side of vehicle)—When the vehicle approaches and departs the facility, the curb must be on the right side of the vehicle. A U-turn is prohibited. This is typically used for vehicles such as buses that must arrive with the bus stop on the right-hand side.
  • 2 (Left side of vehicle)—When the vehicle approaches and departs the facility, the curb must be on the left side of the vehicle. A U-turn is prohibited. This is typically used for vehicles such as buses that must arrive with the bus stop on the left-hand side.
  • 3 (No U-Turn)—When the vehicle approaches the facility, the curb can be on either side of the vehicle, however, the vehicle must depart without turning around.

The CurbApproach attribute is designed to work with both types of national driving standards: right-hand traffic (United States) and left-hand traffic (United Kingdom). First, consider a facility on the left side of a vehicle. It is always on the left side regardless of whether the vehicle travels on the left or right half of the road. What may change with national driving standards is your decision to approach a facility from one of two directions; that is, so it ends up on the right or left side of the vehicle. For example, if you want to arrive at a facility and not have a lane of traffic between the vehicle and the facility, choose 1 (Right side of vehicle) in the United States and 2 (Left side of vehicle) in the United Kingdom.

Bearing

The direction in which a point is moving. The units are degrees and are measured clockwise from true north. This field is used in conjunction with the BearingTol field.

Bearing data is usually sent automatically from a mobile device equipped with a GPS receiver. Try to include bearing data if you are loading an input location that is moving, such as a pedestrian or a vehicle.

Using this field tends to prevent adding locations to the wrong edges, which can occur when a vehicle is near an intersection or an overpass, for example. Bearing also helps the tool determine on which side of the street the point is.

BearingTol

The bearing tolerance value creates a range of acceptable bearing values when locating moving points on an edge using the Bearing field. If the value from the Bearing field is within the range of acceptable values that are generated from the bearing tolerance on an edge, the point can be added as a network location there; otherwise, the closest point on the next-nearest edge is evaluated.

The units are in degrees, and the default value is 30. Values must be greater than 0 and less than 180. A value of 30 means that when Network Analyst attempts to add a network location on an edge, a range of acceptable bearing values is generated 15 degrees to either side of the edge (left and right) and in both digitized directions of the edge.

NavLatency

This field is only used in the solve process if Bearing and BearingTol also have values; however, entering a NavLatency value is optional, even when values are present in Bearing and BearingTol. NavLatency indicates how much cost is expected to elapse from the moment GPS information is sent from a moving vehicle to a server and the moment the processed route is received by the vehicle's navigation device.

The units of NavLatency are the same as the units of the impedance attribute.

Break_Values

The size and number of service area polygons to generate for each facility. The units are determined by the Break Units value.

Multiple polygon breaks can be set to create concentric service areas per facility. For instance, to find 2-, 3-, and 5-mile service areas for each facility, type 2 3 5, separating the values with a space, and set Break Units to Miles. There is no limit to the number of break values you specify.

The size of the maximum break value can't exceed the equivalent of 300 minutes or 300 miles (482.80 kilometers). When generating detailed polygons, the maximum service-area size is limited to 15 minutes and 15 miles (24.14 kilometers).

Break_Units

Specifies the units for the Break Values parameter.

The units you choose for this parameter determine whether the tool will create service areas by measuring driving distance or driving time. Choose a time unit to measure driving time. To measure driving distance, choose a distance unit. Your choice also determines the units in which the tool will report total driving time or distance in the results.

The choices are as follows:

  • Meters
  • Kilometers
  • Feet
  • Yards
  • Miles
  • NauticalMiles
  • Seconds
  • Minutes
  • Hours
  • Days

Analysis_Region (Optional)

This parameter is ignored by the service and specifying a value does not have any effect on the analysis.

Travel_Direction (Optional)

Specifies whether the direction of travel used to generate the service area polygons is toward or away from the facilities.

  • Away from facilities—The service area is generated in the direction away from the facilities.
  • Toward facilities—The service area is created in the direction toward the facilities.

The direction of travel may change the shape of the polygons because impedances on opposite sides of streets may differ or one-way restrictions may exist, such as one-way streets. The direction you should choose depends on the nature of your service area analysis. The service area for a pizza delivery store, for example, should be created away from the facility, whereas the service area of a hospital should be created toward the facility.

Time_of_Day (Optional)

The time to depart from or arrive at the facilities. The interpretation of this value depends on whether travel is toward or away from the facilities.

  • It represents the departure time if Travel Direction is set to Away from facilities.
  • It represents the arrival time if Travel Direction is set to Toward facilities.

You can use the Time Zone for Time of Day parameter to specify whether this time and date refers to UTC or the time zone in which the facility is located.

Repeatedly solving the same analysis, but using different Time of Day values, allows you to see how a facility's reach changes over time. For instance, the five-minute service area around a fire station may start out large in the early morning, diminish during the morning rush hour, grow in the late morning, and so on, throughout the day.

Use_Hierarchy (Optional)

Specifies whether hierarchy will be used when finding the best route between the facility and the incident.

  • Checked (True)—Hierarchy will be used for the analysis. Using a hierarchy results in the solver preferring higher-order edges to lower-order edges. Hierarchical solves are faster, and they can be used to simulate the preference of a driver who chooses to travel on freeways over local roads when possible—even if that means a longer trip.
  • Unchecked (False)—Hierarchy will not be used for the analysis. Not using a hierarchy yields an accurate service area measured along all edges of the network dataset regardless of hierarchy level.

Regardless of whether the Use Hierarchy parameter is checked (True), hierarchy is always used when the largest break value exceeds 240 minutes or 240 miles (386.24 kilometers).

UTurn_at_Junctions (Optional)

Specifies whether to restrict or permit the service area to make U-turns at junctions. To understand the parameter values, consider the following terminology: a junction is a point where a street segment ends and potentially connects to one or more other segments; a pseudojunction is a point where exactly two streets connect to one another; an intersection is a point where three or more streets connect; and a dead end is where one street segment ends without connecting to another.

  • Allowed—U-turns are permitted everywhere. Allowing U-turns implies that the vehicle can turn around at any junction and double back on the same street. This is the default.
  • Not Allowed—U-turns are prohibited at all junctions: pseudojunctions, intersections, and dead ends.
  • Allowed only at Dead Ends—U-turns are prohibited at all junctions, except those that have only one connected street feature (a dead end).
  • Allowed only at Intersections and Dead Ends—U-turns are prohibited at pseudojunctions where exactly two adjacent streets meet, but U-turns are permitted at intersections and dead ends. This prevents turning around in the middle of the road where one length of road happens to be digitized as two street features.

Polygons_for_Multiple_Facilities (Optional)

Specifies how service area polygons will be generated when multiple facilities are present in the analysis.

  • Overlapping—Individual polygons will be created for each facility. The polygons can overlap each other. This is the default.
  • Not Overlapping—Individual polygons will be created such that a polygon from one facility cannot overlap polygons from other facilities. Any portion of the network can only be covered by the service area of the nearest facility.
  • Merge by Break Value—Polygons of different facilities with the same break value will be created and joined.

When using Overlapping or Not Overlapping, all fields from the input facilities are included in the output polygons, with the exception that values from the input ObjectID field are transferred to the FacilityOID field of the output polygons. The FacilityOID field is null when merging by break value, and the input fields are not included in the output.

Polygon_Overlap_Type (Optional)

Specifies whether concentric service area polygons will be created as disks or rings. This option is applicable only when multiple break values are specified for the facilities.

  • Rings—The polygons representing larger breaks exclude the polygons of smaller breaks. This creates polygons between consecutive breaks. Use this option to find the area from one break to another. For instance, if you create 5- and 10-minute service areas, the 10-minute service area polygon will exclude the area under the 5-minute service area polygon. This is the default.
  • Disks—Polygons are created from the facility to the break. For instance, if you create 5- and 10-minute service areas, the 10-minute service area polygon will include the area under the 5-minute service area polygon.

Detailed_Polygons (Optional)

Use of this parameter is no longer recommended. To generate detailed polygons, set the Polygon Detail parameter value to High.

Specifies the option to create detailed or generalized polygons.

  • Unchecked (False)—Generalized polygons are created, which are generated quickly and are fairly accurate. This is the default.
  • Checked (True)—Detailed polygons are created, which accurately model the service area lines and may contain islands of unreached areas. This option is much slower than generating generalized polygons. This option isn't supported when using hierarchy.

The tool supports generating detailed polygons only if the largest value specified in the Break Values parameter is less than or equal to 15 minutes or 15 miles (24.14 kilometers).

Polygon_Trim_Distance (Optional)

The distance within which the service area polygons will be trimmed. This is useful when finding service areas in places that have a sparse street network and you don't want the service area to cover large areas where there are no street features.

The default value is 100 meters. No value or a value of 0 for this parameter specifies that the service area polygons will not be trimmed. This parameter value is ignored when using hierarchy.

Polygon_Simplification_Tolerance (Optional)

The amount by which the polygon geometry will be simplified.

Simplification maintains critical vertices of a polygon to define its essential shape and removes other vertices. The simplification distance you specify is the maximum offset the simplified polygon boundaries can deviate from the original polygon boundaries. Simplifying a polygon reduces the number of vertices and tends to reduce drawing times.

Point_Barriers (Optional)

Use this parameter to specify one or more points that will act as temporary restrictions or represent additional time or distance that may be required to travel on the underlying streets. For example, a point barrier can be used to represent a fallen tree along a street or a time delay spent at a railroad crossing.

The tool imposes a limit of 250 points that can be added as barriers.

When specifying point barriers, you can set properties for each, such as its name or barrier type, using the following attributes:

Name

The name of the barrier.

BarrierType

Specifies whether the point barrier restricts travel completely or adds time or distance when it is crossed. The value for this attribute is specified as one of the following integers (use the numeric code, not the name in parentheses):

  • 0 (Restriction)—Prohibits travel through the barrier. The barrier is referred to as a restriction point barrier since it acts as a restriction.

  • 2 (Added Cost)—Traveling through the barrier increases the travel time or distance by the amount specified in the Additional_Time, Additional_Distance, or Additional_Cost field. This barrier type is referred to as an added cost point barrier.

Additional_Time

The added travel time when the barrier is traversed. This field is applicable only for added-cost barriers and when the Break Units parameter is time-based.

This field value must be greater than or equal to zero, and its units are the same as those specified in the Break Units parameter.

Additional_Distance

The added distance when the barrier is traversed. This field is applicable only for added-cost barriers and when the Break Units parameter is distance-based..

The field value must be greater than or equal to zero, and its units are the same as those specified in the Break Units parameter.

Additional_Cost

The added cost when the barrier is traversed. This field is applicable only for added-cost barriers when the Break Units parameter is neither time-based nor distance-based.

FullEdge

Specifies how the restriction point barriers are applied to the edge elements during the analysis. The field value is specified as one of the following integers (use the numeric code, not the name in parentheses):

  • 0 (False)—Permits travel on the edge up to the barrier but not through it. This is the default value.
  • 1 (True)—Restricts travel anywhere on the associated edge.

CurbApproach

Specifies the direction of traffic that is affected by the barrier. The field value is specified as one of the following integers (use the numeric code, not the name in parentheses):

  • 0 (Either side of vehicle)—The barrier affects travel over the edge in both directions.
  • 1 (Right side of vehicle)—Vehicles are only affected if the barrier is on their right side during the approach. Vehicles that traverse the same edge but approach the barrier on their left side are not affected by the barrier.
  • 2 (Left side of vehicle)—Vehicles are only affected if the barrier is on their left side during the approach. Vehicles that traverse the same edge but approach the barrier on their right side are not affected by the barrier.

Because junctions are points and don't have a side, barriers on junctions affect all vehicles regardless of the curb approach.

The CurbApproach attribute works with both types of national driving standards: right-hand traffic (United States) and left-hand traffic (United Kingdom). First, consider a facility on the left side of a vehicle. It is always on the left side regardless of whether the vehicle travels on the left or right half of the road. What may change with national driving standards is your decision to approach a facility from one of two directions, that is, so it ends up on the right or left side of the vehicle. For example, to arrive at a facility and not have a lane of traffic between the vehicle and the facility, choose 1 (Right side of vehicle) in the United States and 2 (Left side of vehicle) in the United Kingdom.

Bearing

The direction in which a point is moving. The units are degrees and are measured clockwise from true north. This field is used in conjunction with the BearingTol field.

Bearing data is usually sent automatically from a mobile device equipped with a GPS receiver. Try to include bearing data if you are loading an input location that is moving, such as a pedestrian or a vehicle.

Using this field tends to prevent adding locations to the wrong edges, which can occur when a vehicle is near an intersection or an overpass, for example. Bearing also helps the tool determine on which side of the street the point is.

BearingTol

The bearing tolerance value creates a range of acceptable bearing values when locating moving points on an edge using the Bearing field. If the value from the Bearing field is within the range of acceptable values that are generated from the bearing tolerance on an edge, the point can be added as a network location there; otherwise, the closest point on the next-nearest edge is evaluated.

The units are in degrees, and the default value is 30. Values must be greater than 0 and less than 180. A value of 30 means that when Network Analyst attempts to add a network location on an edge, a range of acceptable bearing values is generated 15 degrees to either side of the edge (left and right) and in both digitized directions of the edge.

NavLatency

This field is only used in the solve process if Bearing and BearingTol also have values; however, entering a NavLatency value is optional, even when values are present in Bearing and BearingTol. NavLatency indicates how much cost is expected to elapse from the moment GPS information is sent from a moving vehicle to a server and the moment the processed route is received by the vehicle's navigation device.

The units of NavLatency are the same as the units of the impedance attribute.

Line_Barriers (Optional)

Use this parameter to specify one or more lines that prohibit travel anywhere the lines intersect the streets. For example, a parade or protest that blocks traffic across several street segments can be modeled with a line barrier. A line barrier can also quickly fence off several roads from being traversed, thereby channeling possible routes away from undesirable parts of the street network.

The tool imposes a limit on the number of streets you can restrict using the Line Barriers parameter. While there is no limit to the number of lines you can specify as line barriers, the combined number of streets intersected by all the lines cannot exceed 500.

When specifying the line barriers, you can set name and barrier type properties for each using the following attributes:

Name

The name of the barrier.

Polygon_Barriers (Optional)

Use this parameter to specify polygons that either completely restrict travel or proportionately scale the time or distance required to travel on the streets intersected by the polygons.

The service imposes a limit on the number of streets you can restrict using the Polygon Barriers parameter. While there is no limit to the number of polygons you can specify as polygon barriers, the combined number of streets intersected by all the polygons cannot exceed 2,000.

When specifying the polygon barriers, you can set properties for each, such as its name or barrier type, using the following attributes:

Name

The name of the barrier.

BarrierType

Specifies whether the barrier restricts travel completely or scales the cost (such as time or distance) for traveling through it. The field value is specified as one of the following integers (use the numeric code, not the name in parentheses):

  • 0 (Restriction)—Prohibits traveling through any part of the barrier. The barrier is referred to as a restriction polygon barrier since it prohibits traveling on streets intersected by the barrier. One use of this type of barrier is to model floods covering areas of the street that make traveling on those streets impossible.

  • 1 (Scaled Cost)—Scales the cost (such as travel time or distance) required to travel the underlying streets by a factor specified using the ScaledTimeFactor or ScaledDistanceFactor field. If the streets are partially covered by the barrier, the travel time or distance is apportioned and then scaled. For example, a factor of 0.25 means that travel on underlying streets is expected to be four times faster than normal. A factor of 3.0 means it is expected to take three times longer than normal to travel on underlying streets. This barrier type is referred to as a scaled-cost polygon barrier. It can be used to model storms that reduce travel speeds in specific regions.

ScaledTimeFactor

This is the factor by which the travel time of the streets intersected by the barrier is multiplied. The field value must be greater than zero.

This field is applicable only for scaled-cost barriers and when the Break Units parameter is time-based.

ScaledDistanceFactor

This is the factor by which the distance of the streets intersected by the barrier is multiplied. The field value must be greater than zero.

This field is applicable only for scaled-cost barriers and when the Break Units parameter is distance-based.

ScaledCostFactor

This is the factor by which the cost of the streets intersected by the barrier is multiplied. The field value must be greater than zero.

This field is applicable only for scaled-cost barriers when the Break Units parameter is neither time-based nor distance-based.

Restrictions (Optional)

The travel restrictions that will be honored by the tool when determining the service areas.

A restriction represents a driving preference or requirement. In most cases, restrictions cause roads to be prohibited. For instance, using the Avoid Toll Roads restriction will result in a route that will include toll roads only when it is required to travel on toll roads to visit an incident or a facility. Height Restriction makes it possible to route around any clearances that are lower than the height of your vehicle. If you are carrying corrosive materials on your vehicle, using the Any Hazmat Prohibited restriction prevents hauling the materials along roads where it is marked illegal to do so.

The values you provide for this parameter are ignored unless Travel Mode is set to Custom.

Some restrictions require an additional value to be specified for their use. This value must be associated with the restriction name and a specific parameter intended to work with the restriction. You can identify such restrictions if their names appear in the AttributeName column in the Attribute Parameter Values parameter. The ParameterValue field should be specified in the Attribute Parameter Values parameter for the restriction to be correctly used when finding traversable roads.

Some restrictions are supported only in certain countries; their availability is stated by region in the list below. Of the restrictions that have limited availability within a region, you can determine whether the restriction is available in a particular country by reviewing the table in the Country list section of Network analysis coverage. If a country has a value of Yes in the Logistics Attribute column, the restriction with select availability in the region is supported in that country. If you specify restriction names that are not available in the country where your incidents are located, the service ignores the invalid restrictions. The service also ignores restrictions when the Restriction Usage attribute parameter value is between 0 and 1 (see the Attribute Parameter Value parameter). It prohibits all restrictions when the Restriction Usage parameter value is greater than 0.

The tool supports the following restrictions:

  • Any Hazmat Prohibited—The results will not include roads where transporting any kind of hazardous material is prohibited.

    Availability: Select countries in North America and Europe

  • Avoid Carpool Roads—The results will avoid roads that are designated exclusively for car pool (high-occupancy) vehicles.

    Availability: All countries

  • Avoid Express Lanes—The results will avoid roads designated as express lanes.

    Availability: All countries

  • Avoid Ferries—The results will avoid ferries.

    Availability: All countries

  • Avoid Gates—The results will avoid roads where there are gates, such as keyed access or guard-controlled entryways.

    Availability: All countries

  • Avoid Limited Access Roads—The results will avoid roads that are limited-access highways.

    Availability: All countries

  • Avoid Private Roads—The results will avoid roads that are not publicly owned and maintained.

    Availability: All countries

  • Avoid Roads Unsuitable for Pedestrians—The results will avoid roads that are unsuitable for pedestrians.

    Availability: All countries

  • Avoid Stairways—The results will avoid all stairways on a pedestrian-suitable route.

    Availability: All countries

  • Avoid Toll Roads—The results will avoid all toll roads for automobiles.

    Availability: All countries

  • Avoid Toll Roads for Trucks—The results will avoid all toll roads for trucks.

    Availability: All countries

  • Avoid Truck Restricted Roads—The results will avoid roads where trucks are not allowed, except when making deliveries.

    Availability: All countries

  • Avoid Unpaved Roads—The results will avoid roads that are not paved (for example, dirt, gravel, and so on).

    Availability: All countries

  • Axle Count Restriction—The results will not include roads where trucks with the specified number of axles are prohibited. The number of axles can be specified using the Number of Axles restriction parameter.

    Availability: Select countries in North America and Europe

  • Driving a Bus—The results will not include roads where buses are prohibited. Using this restriction will also ensure that the results will honor one-way streets.

    Availability: All countries

  • Driving a Taxi—The results will not include roads where taxis are prohibited. Using this restriction will also ensure that the results will honor one-way streets.

    Availability: All countries

  • Driving a Truck—The results will not include roads where trucks are prohibited. Using this restriction will also ensure that the results will honor one-way streets.

    Availability: All countries

  • Driving an Automobile—The results will not include roads where automobiles are prohibited. Using this restriction will also ensure that the results will honor one-way streets.

    Availability: All countries

  • Driving an Emergency Vehicle—The results will not include roads where emergency vehicles are prohibited. Using this restriction will also ensure that the results will honor one-way streets.

    Availability: All countries

  • Height Restriction—The results will not include roads where the vehicle height exceeds the maximum allowed height for the road. The vehicle height can be specified using the Vehicle Height (meters) restriction parameter.

    Availability: Select countries in North America and Europe

  • Kingpin to Rear Axle Length Restriction—The results will not include roads where the vehicle length exceeds the maximum allowed kingpin to rear axle for all trucks on the road. The length between the vehicle kingpin and the rear axle can be specified using the Vehicle Kingpin to Rear Axle Length (meters) restriction parameter.

    Availability: Select countries in North America and Europe

  • Length Restriction—The results will not include roads where the vehicle length exceeds the maximum allowed length for the road. The vehicle length can be specified using the Vehicle Length (meters) restriction parameter.

    Availability: Select countries in North America and Europe

  • Preferred for Pedestrians—The results will use preferred routes suitable for pedestrian navigation.

    Availability: Select countries in North America and Europe

  • Riding a Motorcycle—The results will not include roads where motorcycles are prohibited. Using this restriction will also ensure that the results will honor one-way streets.

    Availability: All countries

  • Roads Under Construction Prohibited—The results will not include roads that are under construction.

    Availability: All countries

  • Semi or Tractor with One or More Trailers Prohibited—The results will not include roads where semis or tractors with one or more trailers are prohibited.

    Availability: Select countries in North America and Europe

  • Single Axle Vehicles Prohibited—The results will not include roads where vehicles with single axles are prohibited.

    Availability: Select countries in North America and Europe

  • Tandem Axle Vehicles Prohibited—The results will not include roads where vehicles with tandem axles are prohibited.

    Availability: Select countries in North America and Europe

  • Through Traffic Prohibited—The results will not include roads where through traffic (non-local) is prohibited.

    Availability: All countries

  • Truck with Trailers Restriction—The results will not include roads where trucks with the specified number of trailers on the truck are prohibited. The number of trailers on the truck can be specified using the Number of Trailers on Truck restriction parameter.

    Availability: Select countries in North America and Europe

  • Use Preferred Hazmat Routes—The results will prefer roads that are designated for transporting any kind of hazardous materials.

    Availability: Select countries in North America and Europe

  • Use Preferred Truck Routes—The results will prefer roads that are designated as truck routes, such as the roads that are part of the national network as specified by the National Surface Transportation Assistance Act in the United States, or roads that are designated as truck routes by the state or province, or roads that are preferred by truckers when driving in an area.

    Availability: Select countries in North America and Europe

  • Walking—The results will not include roads where pedestrians are prohibited.

    Availability: All countries

  • Weight Restriction—The results will not include roads where the vehicle weight exceeds the maximum allowed weight for the road. The vehicle weight can be specified using the Vehicle Weight (kilograms) restriction parameter.

    Availability: Select countries in North America and Europe

  • Weight per Axle Restriction—The results will not include roads where the vehicle weight per axle exceeds the maximum allowed weight per axle for the road. The vehicle weight per axle can be specified using the Vehicle Weight per Axle (kilograms) restriction parameter.

    Availability: Select countries in North America and Europe

  • Width Restriction—The results will not include roads where the vehicle width exceeds the maximum allowed width for the road. The vehicle width can be specified using the Vehicle Width (meters) restriction parameter.

    Availability: Select countries in North America and Europe

The Driving a Delivery Vehicle restriction attribute is no longer available. The service will ignore this restriction since it is invalid. To achieve similar results, use the Driving a Truck restriction attribute along with the Avoid Truck Restricted Roads restriction attribute.

These value are specific to the services published with the ArcGIS StreetMap Premium data. The values will be different if you are using your own data for the analysis.

Attribute_Parameter_Values (Optional)

Use this parameter to specify additional values required by an attribute or restriction, such as to specify whether the restriction prohibits, avoids, or prefers travel on restricted roads. If the restriction is meant to avoid or prefer roads, you can further specify the degree to which they are avoided or preferred using this parameter. For example, you can choose to never use toll roads, avoid them as much as possible, or prefer them.

The values you provide for this parameter are ignored unless Travel Mode is set to Custom.

If you specify the Attribute Parameter Values parameter from a feature class, the field names on the feature class must match the fields as follows:

  • AttributeName—The name of the restriction.
  • ParameterName—The name of the parameter associated with the restriction. A restriction can have one or more ParameterName field values based on its intended use.
  • ParameterValue—The value for ParameterName used by the tool when evaluating the restriction.

The Attribute Parameter Values parameter is dependent on the Restrictions parameter. The ParameterValue field is applicable only if the restriction name is specified as the value for the Restrictions parameter.

In Attribute Parameter Values, each restriction (listed as AttributeName) has a ParameterName field value, Restriction Usage, that specifies whether the restriction prohibits, avoids, or prefers travel on the roads associated with the restriction as well as the degree to which the roads are avoided or preferred. The Restriction Usage ParameterName can be assigned any of the following string values or their equivalent numeric values listed in the parentheses:

  • PROHIBITED (-1)—Travel on the roads using the restriction is completely prohibited.
  • AVOID_HIGH (5)—It is highly unlikely the tool will include in the route the roads that are associated with the restriction.
  • AVOID_MEDIUM (2)—It is unlikely the tool will include in the route the roads that are associated with the restriction.
  • AVOID_LOW (1.3)—It is somewhat unlikely the tool will include in the route the roads that are associated with the restriction.
  • PREFER_LOW (0.8)—It is somewhat likely the tool will include in the route the roads that are associated with the restriction.
  • PREFER_MEDIUM (0.5)—It is likely the tool will include in the route the roads that are associated with the restriction.
  • PREFER_HIGH (0.2)—It is highly likely the tool will include in the route the roads that are associated with the restriction.

In most cases, you can use the default value, PROHIBITED, as the Restriction Usage value if the restriction is dependent on a vehicle characteristic such as vehicle height. However, in some cases, the Restriction Usage value depends on your routing preferences. For example, the Avoid Toll Roads restriction has the default value of AVOID_MEDIUM for the Restriction Usage attribute. This means that when the restriction is used, the tool will try to route around toll roads when it can. AVOID_MEDIUM also indicates how important it is to avoid toll roads when finding the best route; it has a medium priority. Choosing AVOID_LOW puts lower importance on avoiding tolls; choosing AVOID_HIGH instead gives it a higher importance and thus makes it more acceptable for the service to generate longer routes to avoid tolls. Choosing PROHIBITED entirely disallows travel on toll roads, making it impossible for a route to travel on any portion of a toll road. Keep in mind that avoiding or prohibiting toll roads, and thus avoiding toll payments, is the objective for some. In contrast, others prefer to drive on toll roads, because avoiding traffic is more valuable to them than the money spent on tolls. In the latter case, choose PREFER_LOW, PREFER_MEDIUM, or PREFER_HIGH as the value for Restriction Usage. The higher the preference, the farther the tool will go out of its way to travel on the roads associated with the restriction.

Time_Zone_for_Time_of_Day (Optional)

Specifies the time zone or zones of the Time of Day parameter.

  • Geographically Local—The Time of Day parameter refers to the time zone or zones in which the facilities are located. The start or end times of the service areas are staggered by time zone. Setting Time of Day to 9:00 AM, choosing Geographically Local for Time Zone for Time of Day, and solving causes service areas to be generated for 9:00 a.m. eastern time for any facilities in the eastern time zone, 9:00 a.m. central time for facilities in the central time zone, 9:00 a.m. mountain time for facilities in the mountain time zone, and so on, for facilities in different time zones.

    If stores in a chain that span the U.S. open at 9:00 a.m. local time, this parameter value can be chosen to find market territories at opening time for all stores in one solve. First, the stores in the eastern time zone open and a polygon is generated, then an hour later stores open in central time, and so on. Nine o'clock is always in local time but staggered in real time.

  • UTC—The Time of Day parameter refers to coordinated universal time (UTC). All facilities are reached or departed from simultaneously, regardless of the time zone each is in.

    Setting Time of Day to 2:00 PM, choosing UTC, and solving causes service areas to be generated for 9:00 a.m. eastern standard time for any facilities in the eastern time zone, 8:00 a.m. central standard time for facilities in the central time zone, 7:00 a.m. mountain standard time for facilities in the mountain time zone, and so on, for facilities in different time zones.

    The scenario above assumes standard time. During daylight saving time, the eastern, central, and mountain times will each be one hour ahead (that is, 10:00, 9:00, and 8:00 a.m., respectively).

    One of the cases in which the UTC option is useful is to visualize emergency-response coverage for a jurisdiction that is split into two time zones. The emergency vehicles are loaded as facilities. Time of Day is set to now in UTC. (You need to determine the current time and date in terms of UTC to correctly use this option.) Other properties are set and the analysis is solved. Even though a time-zone boundary divides the vehicles, the results show areas that can be reached given current traffic conditions. This same process can be used for other times as well, not just for now.

Regardless of the Time Zone for Time of Day setting, all facilities must be in the same time zone when Time of Day has a nonnull value and Polygons for Multiple Facilities is set to create merged or nonoverlapping polygons.

Travel_Mode (Optional)

The mode of transportation to model in the analysis. Travel modes are managed in ArcGIS Online and can be configured by the administrator of your organization to reflect your organization's workflows. You need to specify the name of a travel mode that is supported by your organization.

To get a list of supported travel mode names, use the same GIS server connection you used to access this tool, and run the GetTravelModes tool in the Utilities toolbox. The GetTravelModes tool adds the Supported Travel Modes table to the application. Any value in the Travel Mode Name field from the Supported Travel Modes table can be specified as input. You can also specify the value from the Travel Mode Settings field as input. This reduces the tool execution time because the tool does not have to find the settings based on the travel mode name.

The default value, Custom, allows you to configure your own travel mode using the custom travel mode parameters (UTurn at Junctions, Use Hierarchy, Restrictions, Attribute Parameter Values, and Impedance). The default values of the custom travel mode parameters model traveling by car. You can also choose Custom and set the custom travel mode parameters listed above to model a pedestrian with a fast walking speed or a truck with a given height, weight, and cargo of certain hazardous materials. You can try different settings to get the analysis results you want. Once you have identified the analysis settings, work with your organization's administrator and save these settings as part of a new or existing travel mode so that everyone in your organization can run the analysis with the same settings.

When you choose Custom, the values you set for the custom travel mode parameters are included in the analysis. Specifying another travel mode, as defined by your organization, causes any values you set for the custom travel mode parameters to be ignored; the tool overrides them with values from your specified travel mode.

Impedance (Optional)

Specifies the impedance, which is a value that represents the effort or cost of traveling along road segments or on other parts of the transportation network.

Travel time is an impedance: a car may take 1 minute to travel a mile along an empty road. Travel times can vary by travel mode—a pedestrian may take more than 20 minutes to walk the same mile, so it is important to choose the right impedance for the travel mode you are modeling.

Travel distance can also be an impedance; the length of a road in kilometers can be thought of as impedance. Travel distance in this sense is the same for all modes—a kilometer for a pedestrian is also a kilometer for a car. (What may change is the pathways on which the different modes are allowed to travel, which affects distance between points, and this is modeled by travel mode settings.)

The value you provide for this parameter is ignored unless Travel Mode is set to Custom, which is the default value.

Choose from the following impedance values:

  • TravelTime—Historical and live traffic data is used. This option is good for modeling the time it takes automobiles to travel along roads at a specific time of day using live traffic speed data where available. When using TravelTime, you can optionally set the TravelTime::Vehicle Maximum Speed (km/h) attribute parameter to specify the physical limitation of the speed the vehicle is capable of traveling.
  • Minutes—Live traffic data is not used, but historical average speeds for automobiles data is used.
  • TruckTravelTime—Historical and live traffic data is used, but the speed is capped at the posted truck speed limit. This is good for modeling the time it takes for the trucks to travel along roads at a specific time. When using TruckTravelTime, you can optionally set the TruckTravelTime::Vehicle Maximum Speed (km/h) attribute parameter to specify the physical limitation of the speed the truck is capable of traveling.
  • TruckMinutes—Live traffic data is not used, but the smaller of the historical average speeds for automobiles and the posted speed limits for trucks are used.
  • WalkTime—The default is a speed of 5 km/hr on all roads and paths, but this can be configured through the WalkTime::Walking Speed (km/h) attribute parameter.
  • Miles—Length measurements along roads are stored in miles and can be used for performing analysis based on shortest distance.
  • Kilometers—Length measurements along roads are stored in kilometers and can be used for performing analysis based on shortest distance.
  • TimeAt1KPH—The default is a speed of 1 km/hr on all roads and paths. The speed cannot be changed using any attribute parameter.

These value are specific to the services published with the ArcGIS StreetMap Premium data. The values will be different if you are using your own data for the analysis.

If you choose a time-based impedance, such as TravelTime, TruckTravelTime, Minutes, TruckMinutes, or WalkTime, the Break Units parameter must be set to a time-based value; if you choose a distance-based impedance such as Miles, Kilometers, Break Units must be distance-based.

Drive Time, Truck Time, Walk Time, and Travel Distance impedance values are no longer supported and will be removed in a future release. If you use one of these values, the tool uses the value of the Time Impedance parameter for time-based values and the Distance Impedance parameter for distance-based values.

Save_Output_Network_Analysis_Layer (Optional)

Specifies whether the analysis settings will be saved as a network analysis layer file. You cannot directly work with this file even when you open the file in an ArcGIS Desktop application such as ArcMap. It is meant to be sent to Esri Technical Support to diagnose the quality of results returned from the tool.

  • Checked (True in Python)—The output will be saved as a network analysis layer file. The file will be downloaded to a temporary directory on your machine. In ArcGIS Pro, the location of the downloaded file can be determined by viewing the value for the Output Network Analysis Layer parameter in the entry corresponding to the tool execution in the geoprocessing history of your project. In ArcMap, the location of the file can be determined by accessing the Copy Location option in the shortcut menu on the Output Network Analysis Layer parameter in the entry corresponding to the tool execution in the Geoprocessing Results window.
  • Unchecked (False in Python)—The output will not be saved as a network analysis layer file. This is the default.

Overrides (Optional)

Additional settings that can influence the behavior of the solver when finding solutions for the network analysis problems.

The value for this parameter must be specified in JavaScript Object Notation (JSON). For example, a valid value is of the following form: {"overrideSetting1" : "value1", "overrideSetting2" : "value2"}. The override setting name is always enclosed in double quotation marks. The values can be a number, Boolean, or string.

The default value for this parameter is no value, which indicates not to override any solver settings.

Overrides are advanced settings that should be used only after careful analysis of the results obtained before and after applying the settings. For a list of supported override settings for each solver and their acceptable values, contact Esri Technical Support.

Time_Impedance (Optional)

The time-based impedance is a value that represents the travel time along road segments or on other parts of the transportation network.

These value are specific to the services published with the ArcGIS StreetMap Premium data. The values will be different if you are using your own data for the analysis.

Distance_Impedance (Optional)

The distance-based impedance is a value that represents the travel distance along road segments or on other parts of the transportation network.

These value are specific to the services published with the ArcGIS StreetMap Premium data. The values will be different if you are using your own data for the analysis.

Polygon_Detail (Optional)

Specifies the level of detail for the output polygons.

  • Standard—Polygons will be created with a standard level of detail. Standard polygons are generated quickly and are fairly accurate, but quality deteriorates somewhat as you move toward the borders of the service area polygons. This is the default.
  • Generalized—Generalized polygons will be created using the hierarchy present in the network data source to produce results quickly. Generalized polygons are inferior in quality compared to standard or high-precision polygons.
  • High—Polygons will be created with the highest level of detail. Holes in the polygon may exist; they represent islands of network elements, such as streets, that couldn't be reached without exceeding the cutoff impedance or due to travel restrictions This option should be used for applications in which precise results are important.

If your analysis covers an urban area with a grid-like street network, the difference between generalized and standard polygons will be minimal. However, for mountain and rural roads, the standard and detailed polygons may present significantly more accurate results than generalized polygons.

The tool supports generating high-precision polygons only if the largest value specified in the Break Values parameter is less than or equal to 15 minutes or 15 miles (24.14 kilometers).

Output_Type (Optional)

Specifies the type of output to be generated. Service area output can be line features representing the roads reachable before the cutoffs are exceeded or the polygon features encompassing these lines (representing the reachable area).

  • Polygons—The service area output will contain polygons only. This is the default.
  • Lines—The service area output will contain lines only.
  • Polygons and lines—The service area output will contain both polygons and lines.

Output_Format (Optional)

Specifies the format in which the output features will be created.

  • Feature Set—The output features will be returned as feature classes and tables. This is the default.
  • JSON File—The output features will be returned as a compressed file containing the JSON representation of the outputs. When this option is specified, the output is a single file (with a .zip extension) that contains one or more JSON files (with a .json extension) for each of the outputs created by the service.
  • GeoJSON File—The output features will be returned as a compressed file containing the GeoJSON representation of the outputs. When this option is specified, the output is a single file (with a .zip extension) that contains one or more GeoJSON files (with a .geojson extension) for each of the outputs created by the service.

When a file-based output format, such as JSON File or GeoJSON File, is specified, no outputs will be added to the display because the application, such as ArcMap or ArcGIS Pro, cannot draw the contents of the result file. Instead, the result file is downloaded to a temporary directory on your machine. In ArcGIS Pro, the location of the downloaded file can be determined by viewing the value for the Output Result File parameter in the entry corresponding to the tool execution in the geoprocessing history of your project. In ArcMap, the location of the file can be determined by accessing the Copy Location option in the shortcut menu on the Output Result File parameter in the entry corresponding to the tool execution in the Geoprocessing Results window.

Exclude_Sources_from_Polygon_Generation (Optional)

You can exclude certain network dataset edge sources when generating service area polygons. Polygons will not be generated around the excluded sources, even though they are traversed in the analysis.

Excluding a network source from service area polygons does not prevent those sources from being traversed. Excluding sources from service area polygons only influences the shape of the service area polygons. To prevent traversal of a given network source, you must create an appropriate restriction when defining your network dataset.

This is useful if you have some network sources that you don't want included in the polygon generation because they create less accurate polygons or are inconsequential for the service area analysis. For example, when creating a walk-time service area in a multimodal network that includes streets and metro lines, you should choose to exclude the metro lines from polygon generation. Although travelers can use the metro lines, they cannot stop partway along a metro line and enter a nearby building. Instead, they must travel the full length of the metro line, exit the metro system at a station, and use the streets to walk to the building. Generating a polygon feature around a metro line will be inaccurate.

Accumulate_Attributes (Optional)

A list of cost attributes to be accumulated during analysis. These accumulated attributes are for reference only; the solver only uses the cost attribute used by your designated travel mode when solving the analysis.

For each cost attribute that is accumulated, a Total_[Cost Attribute Name]_[Units] field is populated in the outputs created from the tool.

Ignore_Network_Location_Fields (Optional)

Specifies whether the network location fields will be considered when locating inputs such as stops or facilities on the network.

  • Checked (True in Python)—Network location fields will not be considered when locating the inputs on the network. Instead, the inputs will always be located by performing a spatial search. This is the default value.
  • Unchecked (False in Python)—Network location fields will be considered when locating the inputs on the network.

Ignore_Invalid_Locations (Optional)

Specifies whether invalid input locations will be ignored.

  • Checked—The network locations that are unlocated will be skipped and the analysis will run using valid network locations only. The analysis will also continue if locations are on nontraversable elements or have other errors. This is useful if you know your network locations are not all correct, but you want to run the analysis with the network locations that are valid. This is the default.
  • Unchecked—Do not run the analysis if there are invalid locations. You can then correct these and rerun the analysis.

Code Samples

GenerateServiceAreas example (stand-alone script)

The following Python script demonstrates how to use the GenerateServiceAreas tool in a script.


"""This example shows how to generate 5, 10, 15 minute drive time areas around facilities."""

import sys
import time
import arcpy

# Change the username and password applicable to your own ArcGIS Online account
username = "<your user name>"
password = "<your password>"
sa_service = "https://logistics.arcgis.com/arcgis/services;World/ServiceAreas;{0};{1}".format(username, password)

# Add the geoprocessing service as a toolbox.
# Check https://pro.arcgis.com/en/pro-app/arcpy/functions/importtoolbox.htm for
# other ways in which you can specify credentials to connect to a geoprocessing service.
arcpy.ImportToolbox(sa_service)

# Set the variables to call the tool
facilities = "C:/data/Inputs.gdb/Stores"
output_service_areas = "C:/data/Results.gdb/StoreServiceAreas"

# Call the tool
result = arcpy.GenerateServiceAreas_ServiceAreas(facilities, "5 10 15", "Minutes")
arcpy.AddMessage("Running the analysis with result ID: {}".format(result.resultID))

# Check the status of the result object every 1 second until it has a
# value of 4 (succeeded) or greater
while result.status < 4:
    time.sleep(1)

# print any warning or error messages returned from the tool
result_severity = result.maxSeverity
if result_severity == 2:
    arcpy.AddError("An error occured when running the tool")
    arcpy.AddError(result.getMessages(2))
    sys.exit(2)
elif result_severity == 1:
    arcpy.AddWarning("Warnings were returned when running the tool")
    arcpy.AddWarning(result.getMessages(1))

# Store the output drive time polygons to a geodatabase
result.getOutput(0).save(output_service_areas)

                    

Tags

Drivetime polygons, Drivetime areas, Service areas, Trade areas, Network buffer, Market areas, Sales territories

Credits

Esri and its data vendors.


Use limitations

This geoprocessing tool is available for users with an ArcGIS Online organizational subscription or an ArcGIS Developer account. To access this tool, you'll need to sign in with an account that is a member of an organizational subscription or a developer account. Each successful tool execution incurs service credits.

If you don't have an account, you can sign up for a free trial of ArcGIS or a free ArcGIS Developer account.