2025-01126 SUPPLEMENTAL MATERIAL - Airport South Industrial Annexation (P21-017) (Noticed on 11072025; Published 11072025; Passed for Publication 10212025; Published 10242025) [Updated 11/18/2025 @4:41 PM] - Part 3B — Sacramento City Council, November 18, 2025 (part 5 of 5)

Intersection: 110:

Movement EB EB
Directions Served T T
Maximum Queue (ft) 82 111
Average Queue (ft) 37 60
95th Queue (ft) 69 92
Link Distance (ft) 465 465
Upstream Blk Time (%)
Queuing Penalty (veh)
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Intersection: 201: Airport Blvd & I-5 Southbound Ramp
Movement
Directions Served
Maximum Queue (ft)
Average Queue (ft)
95th Queue (ft)
Link Distance (ft)
Upstream Blk Time (%)
Queuing Penalty (veh)
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Intersection: 203: I-5 Southbound Ramp
Movement NB
Directions Served T
Maximum Queue (ft) 12
Average Queue (ft) 1
95th Queue (ft) 11
Link Distance (ft) 164
Upstream Blk Time (%)
Queuing Penalty (veh)
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Queuing and Blocking Report Cumulative Plus Project
Cumulative plus Project PM PM Peak Hour
Scenario 1 Aiport South Industrial TIA SimTraffic Report

Page 43 ends

Intersection: 204: I-5 Southbound Ramp
Movement
Directions Served
Maximum Queue (ft)
Average Queue (ft)
95th Queue (ft)
Link Distance (ft)
Upstream Blk Time (%)
Queuing Penalty (veh)
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Intersection: 401: I-5 Southbound Ramp
Movement
Directions Served
Maximum Queue (ft)
Average Queue (ft)
95th Queue (ft)
Link Distance (ft)
Upstream Blk Time (%)
Queuing Penalty (veh)
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Intersection: 402:

Movement EB EB
Directions Served T T
Maximum Queue (ft) 141 140
Average Queue (ft) 83 93
95th Queue (ft) 122 128
Link Distance (ft) 480 480
Upstream Blk Time (%)
Queuing Penalty (veh)
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Queuing and Blocking Report Cumulative Plus Project
Cumulative plus Project PM PM Peak Hour
Scenario 1 Aiport South Industrial TIA SimTraffic Report

Page 44 ends

Intersection: 701: Del Paso Rd/Del Paso Road & Balancing Dwy Movement EB EB WB WB SB SB
Directions Served T T T R L R
Maximum Queue (ft) 11 23 6 120 200 70
Average Queue (ft) 0 1 0 8 87 9
95th Queue (ft) 6 11 4 54 190 98
Link Distance (ft) 3005 3005 289 289 316 316
Upstream Blk Time (%) 3 2
Queuing Penalty (veh) 0 0
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Intersection: 1002: Del Paso Road
Movement EB EB EB
Directions Served T T R
Maximum Queue (ft) 846 867 875
Average Queue (ft) 277 289 235
95th Queue (ft) 874 906 882
Link Distance (ft) 883 883 883
Upstream Blk Time (%) 5 13 16
Queuing Penalty (veh) 24 58 74
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Intersection: 1003: Del Paso Road
Movement EB EB
Directions Served T TR
Maximum Queue (ft) 769 769
Average Queue (ft) 477 480
95th Queue (ft) 1028 1028
Link Distance (ft) 748 748
Upstream Blk Time (%) 29 23
Queuing Penalty (veh) 184 148
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Queuing and Blocking Report Cumulative Plus Project
Cumulative plus Project PM PM Peak Hour
Scenario 1 Aiport South Industrial TIA SimTraffic Report

Page 45 ends

Intersection: 1004: Del Paso Road/Del Paso Rd
Movement EB EB EB WB
Directions Served T T T TR
Maximum Queue (ft) 251 276 262 263
Average Queue (ft) 186 195 175 9
95th Queue (ft) 328 349 337 106
Link Distance (ft) 212 212 212 370
Upstream Blk Time (%) 37 17 9
Queuing Penalty (veh) 290 133 70
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Intersection: 1005: Del Paso Rd/Del Paso Road
Movement EB EB EB WB WB WB
Directions Served T T T T T T
Maximum Queue (ft) 582 581 559 326 374 363
Average Queue (ft) 495 418 365 25 87 90
95th Queue (ft) 747 709 665 159 218 225
Link Distance (ft) 370 370 370 686 686 686
Upstream Blk Time (%) 83 43 19 0
Queuing Penalty (veh) 649 336 151 0
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Intersection: 1006: I-5 Southbound Ramps
Movement SB B1009
Directions Served T T
Maximum Queue (ft) 937 1010
Average Queue (ft) 370 305
95th Queue (ft) 1081 1024
Link Distance (ft) 839 977
Upstream Blk Time (%) 28 19
Queuing Penalty (veh) 0 0
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Queuing and Blocking Report Cumulative Plus Project
Cumulative plus Project PM PM Peak Hour
Scenario 1 Aiport South Industrial TIA SimTraffic Report

Page 46 ends

Intersection: 1007:

Movement EB EB
Directions Served T T
Maximum Queue (ft) 87 92
Average Queue (ft) 44 54
95th Queue (ft) 75 78
Link Distance (ft) 152 152
Upstream Blk Time (%)
Queuing Penalty (veh)
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Intersection: 1011:

Movement SB
Directions Served T
Maximum Queue (ft) 292
Average Queue (ft) 95
95th Queue (ft) 204
Link Distance (ft) 1004
Upstream Blk Time (%)
Queuing Penalty (veh)
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Intersection: 1301: West Elkhorn Boulevard
Movement EB EB
Directions Served T T
Maximum Queue (ft) 11 47
Average Queue (ft) 1 2
95th Queue (ft) 11 35
Link Distance (ft) 212 212
Upstream Blk Time (%) 0
Queuing Penalty (veh) 0
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Queuing and Blocking Report Cumulative Plus Project
Cumulative plus Project PM PM Peak Hour
Scenario 1 Aiport South Industrial TIA SimTraffic Report

Page 47 ends

Intersection: 1302: West Elkhorn Boulevard
Movement EB EB EB
Directions Served T T T
Maximum Queue (ft) 65 38 49
Average Queue (ft) 10 6 5
95th Queue (ft) 62 47 37
Link Distance (ft) 275 275 275
Upstream Blk Time (%)
Queuing Penalty (veh)
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Intersection: 1401: West Elkhorn Boulevard
Movement
Directions Served
Maximum Queue (ft)
Average Queue (ft)
95th Queue (ft)
Link Distance (ft)
Upstream Blk Time (%)
Queuing Penalty (veh)
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Intersection: 1402: West Elkhorn Boulevard
Movement
Directions Served
Maximum Queue (ft)
Average Queue (ft)
95th Queue (ft)
Link Distance (ft)
Upstream Blk Time (%)
Queuing Penalty (veh)
Storage Bay Dist (ft)
Storage Blk Time (%)
Queuing Penalty (veh)
Network Summary
Network wide Queuing Penalty: 8848
SACRAME NTO SOU TH A IRPORT INDUS TR IA L DEVE LOPME NT • LOCAL TRA NSPOR TAT ION A NA LYS IS REPORT • JA N . 30 , 2024
APPENDIX H:

Signal Warrant Analysis
MUTCD Warrant 3

Page 1 of 2 ends

Major Street: 2 or More Lanes
Minor Street: 1 Lane
Yes
Yes
Yes
Yes
Total Number of Unique Hours Met
On Figure 4C-3
0 Hour Interval Major Street Combined Highest Minor Street Approach Beginning At Vehicles Per Hour (VPH) Vehicles Per Hour (VPH) 6:45 AM 385 180
7:00 AM 515 240
7:15 AM 387 180
7:30 AM 259 120
7:45 AM 130 60
8:00 AM 0 0
8:15 AM 0 0
8:30 AM 0 0
8:45 AM 0 0
9:00 AM 0 0
9:15 AM 0 0
1:30 PM 0 0
1:45 PM 0 0
2:00 PM 0 0
2:15 PM 0 0
2:30 PM 0 0
2:45 PM 0 0
3:00 PM 0 0
3:15 PM 0 0
3:30 PM 0 0
3:45 PM 0 0
4:00 PM 0 0
4:15 PM 147 61
4:30 PM 293 124
4:45 PM 439 187
5:00 PM 585 250
5:15 PM 438 189
5:30 PM 292 126
5:45 PM 146 63
6:00 PM 0 0
6:15 PM 0 0
6:30 PM 0 0
6:45 PM 0 0
Does the total stopped time delay experienced by the traffic on one minor-street approach (one direction only) controlled by a STOP sign equal or exceed 4 vehicle-hours for a one-lane approach or 5 vehicle-hours for a two-lane approach? Does the volume on the same minor-street approach (one direction only) equal or exceed 100 vehicles per hour for one moving lane of traffic or 150 vehicles per hour for two moving lanes?
Built-up Isolated Community With Less Than 10,000 Population or Above 40 MPH on Major Street?
MUTCD WARRANT 3, PEAK HOUR
Number of Lanes for Moving Traffic on Each
Approach
No
Hourly Vehicular Volume
Hour Met?
Does the total entering volume serviced during the hour equal or exceed 650 vehicles per hour for intersection with three approaches or 800 vehicles per hour for intersections with four or more approaches?
Indicate whether all three of the following conditions for the same 1 hour (any four consecutive 15- minute periods) of an average day are present*
*If applicable, attach all supporting calculations and documentation.

Is this signal warrant being applied for an unusual case, such as office complexes, manufacturing plants, industrial complexes, or high-occupancy vehicle facilities that attract or discharge large numbers of vehicles over a short time? 6/2/2023 CAMUTCD Signal Warrants_Elkhorn_PowerLine_CumulativeNP.xlsm Elkhorn Blvd at Power Line Rd - Cumulative
MUTCD Warrant 3

Page 2 of 2 ends

0 100
200
300
400
500
300 400 500 600 700 800 900 1000 1100 1200 1300
Minor Street Higher-Volume Approach - VPH
Major Street - Total of Both Approaches - Vehicles Per Hour (VPH) MUTCD Figure 4C-4. Warrant 3, Peak Hour (70% Factor)
0 100
200
300
400
500
600
400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 Minor Street Higher-Volume Approach - VPH
Major Street - Total of Both Approaches - Vehicles Per Hour (VPH) MUTCD Figure 4C-3. Warrant 3, Peak Hour
6/2/2023 CAMUTCD Signal Warrants_Elkhorn_PowerLine_CumulativeNP.xlsm MUTCD Warrant 3

Page 1 of 2 ends

Major Street: 2 or More Lanes
Minor Street: 1 Lane
Yes
Yes
Yes
Yes
Total Number of Unique Hours Met
On Figure 4C-3
1 Hour Interval Major Street Combined Highest Minor Street Approach Beginning At Vehicles Per Hour (VPH) Vehicles Per Hour (VPH) 6:45 AM 228 540
7:00 AM 304 720 Met
7:15 AM 228 540
7:30 AM 152 360
7:45 AM 76 180
8:00 AM 0 0
8:15 AM 0 0
8:30 AM 0 0
8:45 AM 0 0
9:00 AM 0 0
9:15 AM 0 0
1:30 PM 0 0
1:45 PM 0 0
2:00 PM 0 0
2:15 PM 0 0
2:30 PM 0 0
2:45 PM 0 0
3:00 PM 0 0
3:15 PM 0 0
3:30 PM 0 0
3:45 PM 0 0
4:00 PM 0 0
4:15 PM 86 116
4:30 PM 172 232
4:45 PM 258 348
5:00 PM 345 465
5:15 PM 259 349
5:30 PM 173 233
5:45 PM 87 117
6:00 PM 0 0
6:15 PM 0 0
6:30 PM 0 0
6:45 PM 0 0
7:00 PM 0 0
Hour Met?
Does the total entering volume serviced during the hour equal or exceed 650 vehicles per hour for intersection with three approaches or 800 vehicles per hour for intersections with four or more approaches?
Indicate whether all three of the following conditions for the same 1 hour (any four consecutive 15- minute periods) of an average day are present*
*If applicable, attach all supporting calculations and documentation.

Is this signal warrant being applied for an unusual case, such as office complexes, manufacturing plants, industrial complexes, or high-occupancy vehicle facilities that attract or discharge large numbers of vehicles over a short time? Built-up Isolated Community With Less Than 10,000 Population or Above 40 MPH on Major Street?
MUTCD WARRANT 3, PEAK HOUR
Number of Lanes for Moving Traffic on Each
Approach
No
Hourly Vehicular Volume
Does the total stopped time delay experienced by the traffic on one minor-street approach (one direction only) controlled by a STOP sign equal or exceed 4 vehicle-hours for a one-lane approach or 5 vehicle-hours for a two-lane approach? Does the volume on the same minor-street approach (one direction only) equal or exceed 100 vehicles per hour for one moving lane of traffic or 150 vehicles per hour for two moving lanes?
6/2/2023 CAMUTCD Signal Warrants_Metro Air_Airport Industrial.xlsm Metro Air Parkway at South Airport Industrial Blvd
MUTCD Warrant 3

Page 2 of 2 ends

Page 1 of 2 ends

Major Street: 2 or More Lanes
Minor Street: 2 or More Lanes
Yes
Yes
Yes
Yes
Total Number of Unique Hours Met
On Figure 4C-3
0 Hour Interval Major Street Combined Highest Minor Street Approach Beginning At Vehicles Per Hour (VPH) Vehicles Per Hour (VPH) 6:45 AM 424 284
7:00 AM 565 380
7:15 AM 424 286
7:30 AM 283 191
7:45 AM 141 96
8:00 AM 0 0
8:15 AM 0 0
8:30 AM 0 0
8:45 AM 0 0
9:00 AM 0 0
9:15 AM 0 0
1:30 PM 0 0
1:45 PM 0 0
2:00 PM 0 0
2:15 PM 0 0
2:30 PM 0 0
2:45 PM 0 0
3:00 PM 0 0
3:15 PM 0 0
3:30 PM 0 0
3:45 PM 0 0
4:00 PM 0 0
4:15 PM 76 143
4:30 PM 153 286
4:45 PM 229 430
5:00 PM 305 575
5:15 PM 229 432
5:30 PM 152 289
5:45 PM 76 145
6:00 PM 0 0
6:15 PM 0 0
6:30 PM 0 0
6:45 PM 0 0
7:00 PM 0 0
Hour Met?
Does the total entering volume serviced during the hour equal or exceed 650 vehicles per hour for intersection with three approaches or 800 vehicles per hour for intersections with four or more approaches?
Indicate whether all three of the following conditions for the same 1 hour (any four consecutive 15- minute periods) of an average day are present*
*If applicable, attach all supporting calculations and documentation.

Is this signal warrant being applied for an unusual case, such as office complexes, manufacturing plants, industrial complexes, or high-occupancy vehicle facilities that attract or discharge large numbers of vehicles over a short time? Built-up Isolated Community With Less Than 10,000 Population or Above 40 MPH on Major Street?
MUTCD WARRANT 3, PEAK HOUR
Number of Lanes for Moving Traffic on Each
Approach
No
Hourly Vehicular Volume
Does the total stopped time delay experienced by the traffic on one minor-street approach (one direction only) controlled by a STOP sign equal or exceed 4 vehicle-hours for a one-lane approach or 5 vehicle-hours for a two-lane approach? Does the volume on the same minor-street approach (one direction only) equal or exceed 100 vehicles per hour for one moving lane of traffic or 150 vehicles per hour for two moving lanes?
6/2/2023 CAMUTCD Signal Warrants_Metro Air_Elkhorn_BaselineNP.xlsm Metro Air Parkway at West Elkhorn Blvd - Baseline
MUTCD Warrant 3

Page 2 of 2 ends

Page 1 of 2 ends

Major Street: 2 or More Lanes
Minor Street: 1 Lane
Yes
Yes
Yes
Yes
Total Number of Unique Hours Met
On Figure 4C-3
1 Hour Interval Major Street Combined Highest Minor Street Approach Beginning At Vehicles Per Hour (VPH) Vehicles Per Hour (VPH) 6:45 AM 799 111
7:00 AM 1065 150
7:15 AM 799 113
7:30 AM 533 76
7:45 AM 266 39
8:00 AM 0 0
8:15 AM 0 0
8:30 AM 0 0
8:45 AM 0 0
9:00 AM 0 0
9:15 AM 0 0
1:30 PM 0 0
1:45 PM 0 0
2:00 PM 0 0
2:15 PM 0 0
2:30 PM 0 0
2:45 PM 0 0
3:00 PM 0 0
3:15 PM 0 0
3:30 PM 0 0
3:45 PM 0 0
4:00 PM 0 0
4:15 PM 242 79
4:30 PM 485 159
4:45 PM 728 239
5:00 PM 970 320 Met
5:15 PM 728 241
5:30 PM 485 161
5:45 PM 242 81
6:00 PM 0 0
6:15 PM 0 0
6:30 PM 0 0
6:45 PM 0 0
Hour Met?
Does the total entering volume serviced during the hour equal or exceed 650 vehicles per hour for intersection with three approaches or 800 vehicles per hour for intersections with four or more approaches?
Indicate whether all three of the following conditions for the same 1 hour (any four consecutive 15- minute periods) of an average day are present*
*If applicable, attach all supporting calculations and documentation.

Is this signal warrant being applied for an unusual case, such as office complexes, manufacturing plants, industrial complexes, or high-occupancy vehicle facilities that attract or discharge large numbers of vehicles over a short time? Built-up Isolated Community With Less Than 10,000 Population or Above 40 MPH on Major Street?
MUTCD WARRANT 3, PEAK HOUR
Number of Lanes for Moving Traffic on Each
Approach
No
Hourly Vehicular Volume
Does the total stopped time delay experienced by the traffic on one minor-street approach (one direction only) controlled by a STOP sign equal or exceed 4 vehicle-hours for a one-lane approach or 5 vehicle-hours for a two-lane approach? Does the volume on the same minor-street approach (one direction only) equal or exceed 100 vehicles per hour for one moving lane of traffic or 150 vehicles per hour for two moving lanes?
6/2/2023 CAMUTCD Signal Warrants_Metro Air_Lone Tree_BaselineProject.xlsm West Elkhorn Blvd at Lone Tree Rd - Baseline w/ Project MUTCD Warrant 3

Page 2 of 2 ends

0 100
200
300
400
500
300 400 500 600 700 800 900 1000 1100 1200 1300
Minor Street Higher-Volume Approach - VPH
Major Street - Total of Both Approaches - Vehicles Per Hour (VPH) MUTCD Figure 4C-4. Warrant 3, Peak Hour (70% Factor)
0 100
200
300
400
500
600
400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 Minor Street Higher-Volume Approach - VPH
Major Street - Total of Both Approaches - Vehicles Per Hour (VPH) MUTCD Figure 4C-3. Warrant 3, Peak Hour
6/2/2023 CAMUTCD Signal Warrants_Metro Air_Lone Tree_BaselineProject.xlsm MUTCD Warrant 3

Page 1 of 2 ends

Major Street: 2 or More Lanes
Minor Street: 2 or More Lanes
Yes
Yes
Yes
Yes
Total Number of Unique Hours Met
On Figure 4C-3
2 Hour Interval Major Street Combined Highest Minor Street Approach Beginning At Vehicles Per Hour (VPH) Vehicles Per Hour (VPH) 6:45 AM 494 566
7:00 AM 660 755 Met
7:15 AM 495 567
7:30 AM 331 378
7:45 AM 166 189
8:00 AM 0 0
8:15 AM 0 0
8:30 AM 0 0
8:45 AM 0 0
9:00 AM 0 0
9:15 AM 0 0
1:30 PM 0 0
1:45 PM 0 0
2:00 PM 0 0
2:15 PM 0 0
2:30 PM 0 0
2:45 PM 0 0
3:00 PM 0 0
3:15 PM 0 0
3:30 PM 0 0
3:45 PM 0 0
4:00 PM 0 0
4:15 PM 150 177
4:30 PM 300 354
4:45 PM 450 532
5:00 PM 600 710 Met
5:15 PM 450 533
5:30 PM 300 356
5:45 PM 150 178
6:00 PM 0 0
6:15 PM 0 0
6:30 PM 0 0
6:45 PM 0 0
7:00 PM 0 0
Does the total stopped time delay experienced by the traffic on one minor-street approach (one direction only) controlled by a STOP sign equal or exceed 4 vehicle-hours for a one-lane approach or 5 vehicle-hours for a two-lane approach? Does the volume on the same minor-street approach (one direction only) equal or exceed 100 vehicles per hour for one moving lane of traffic or 150 vehicles per hour for two moving lanes?
Built-up Isolated Community With Less Than 10,000 Population or Above 40 MPH on Major Street?
MUTCD WARRANT 3, PEAK HOUR
Number of Lanes for Moving Traffic on Each
Approach
No
Hourly Vehicular Volume
Hour Met?
Does the total entering volume serviced during the hour equal or exceed 650 vehicles per hour for intersection with three approaches or 800 vehicles per hour for intersections with four or more approaches?
Indicate whether all three of the following conditions for the same 1 hour (any four consecutive 15- minute periods) of an average day are present*
*If applicable, attach all supporting calculations and documentation.

Is this signal warrant being applied for an unusual case, such as office complexes, manufacturing plants, industrial complexes, or high-occupancy vehicle facilities that attract or discharge large numbers of vehicles over a short time? 6/2/2023 CAMUTCD Signal Warrants_Metro Air_Elkhorn_BaselineProject.xlsm Metro Air Parkway at West Elkhorn Blvd - Baseline w/ Project MUTCD Warrant 3

Page 2 of 2 ends

0 100
200
300
400
500
300 400 500 600 700 800 900 1000 1100 1200 1300
Minor Street Higher-Volume Approach - VPH
Major Street - Total of Both Approaches - Vehicles Per Hour (VPH) MUTCD Figure 4C-4. Warrant 3, Peak Hour (70% Factor)
0 100
200
300
400
500
600
400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 Minor Street Higher-Volume Approach - VPH
Major Street - Total of Both Approaches - Vehicles Per Hour (VPH) MUTCD Figure 4C-3. Warrant 3, Peak Hour
6/2/2023 CAMUTCD Signal Warrants_Metro Air_Elkhorn_BaselineProject.xlsm MUTCD Warrant 3

Page 1 of 2 ends

Major Street: 2 or More Lanes
Minor Street: 1 Lane
Yes
Yes
Yes
Yes
Total Number of Unique Hours Met
On Figure 4C-3
3 Hour Interval Major Street Combined Highest Minor Street Approach Beginning At Vehicles Per Hour (VPH) Vehicles Per Hour (VPH) 6:45 AM 1024 513 Met
7:00 AM 1365 685 Met
7:15 AM 1024 514 Met
7:30 AM 683 343
7:45 AM 341 172
8:00 AM 0 0
8:15 AM 0 0
8:30 AM 0 0
8:45 AM 0 0
9:00 AM 0 0
9:15 AM 0 0
1:30 PM 0 0
1:45 PM 0 0
2:00 PM 0 0
2:15 PM 0 0
2:30 PM 0 0
2:45 PM 0 0
3:00 PM 0 0
3:15 PM 0 0
3:30 PM 0 0
3:45 PM 0 0
4:00 PM 0 0
4:15 PM 917 138
4:30 PM 1833 277 Met
4:45 PM 2749 416 Met
5:00 PM 3665 555 Met
5:15 PM 2748 417 Met
5:30 PM 1832 278 Met
5:45 PM 916 139
6:00 PM 0 0
6:15 PM 0 0
6:30 PM 0 0
6:45 PM 0 0
7:00 PM 0 0
Does the total stopped time delay experienced by the traffic on one minor-street approach (one direction only) controlled by a STOP sign equal or exceed 4 vehicle-hours for a one-lane approach or 5 vehicle-hours for a two-lane approach? Does the volume on the same minor-street approach (one direction only) equal or exceed 100 vehicles per hour for one moving lane of traffic or 150 vehicles per hour for two moving lanes?
Built-up Isolated Community With Less Than 10,000 Population or Above 40 MPH on Major Street?
MUTCD WARRANT 3, PEAK HOUR
Number of Lanes for Moving Traffic on Each
Approach
No
Hourly Vehicular Volume
Hour Met?
Does the total entering volume serviced during the hour equal or exceed 650 vehicles per hour for intersection with three approaches or 800 vehicles per hour for intersections with four or more approaches?
Indicate whether all three of the following conditions for the same 1 hour (any four consecutive 15- minute periods) of an average day are present*
*If applicable, attach all supporting calculations and documentation.

Is this signal warrant being applied for an unusual case, such as office complexes, manufacturing plants, industrial complexes, or high-occupancy vehicle facilities that attract or discharge large numbers of vehicles over a short time? 6/2/2023 CAMUTCD Signal Warrants_Metro Air_Hwy Commercial.xlsm Metro Air Parkway at Highway Commercial Driveway
MUTCD Warrant 3

Page 2 of 2 ends

Page 1 of 2 ends

Major Street: 2 or More Lanes
Minor Street: 2 or More Lanes
Yes
Yes
Yes
Yes
Total Number of Unique Hours Met
On Figure 4C-3
2 Hour Interval Major Street Combined Highest Minor Street Approach Beginning At Vehicles Per Hour (VPH) Vehicles Per Hour (VPH) 6:45 AM 794 810 Met
7:00 AM 1060 1080 Met
7:15 AM 796 810 Met
7:30 AM 531 540
7:45 AM 266 270
8:00 AM 0 0
8:15 AM 0 0
8:30 AM 0 0
8:45 AM 0 0
9:00 AM 0 0
9:15 AM 0 0
1:30 PM 0 0
1:45 PM 0 0
2:00 PM 0 0
2:15 PM 0 0
2:30 PM 0 0
2:45 PM 0 0
3:00 PM 0 0
3:15 PM 0 0
3:30 PM 0 0
3:45 PM 0 0
4:00 PM 0 0
4:15 PM 371 237
4:30 PM 742 474
4:45 PM 1113 712 Met
5:00 PM 1485 950 Met
5:15 PM 1114 713 Met
5:30 PM 743 476
5:45 PM 372 238
6:00 PM 0 0
6:15 PM 0 0
6:30 PM 0 0
6:45 PM 0 0
Does the total stopped time delay experienced by the traffic on one minor-street approach (one direction only) controlled by a STOP sign equal or exceed 4 vehicle-hours for a one-lane approach or 5 vehicle-hours for a two-lane approach? Does the volume on the same minor-street approach (one direction only) equal or exceed 100 vehicles per hour for one moving lane of traffic or 150 vehicles per hour for two moving lanes?
Built-up Isolated Community With Less Than 10,000 Population or Above 40 MPH on Major Street?
MUTCD WARRANT 3, PEAK HOUR
Number of Lanes for Moving Traffic on Each
Approach
No
Hourly Vehicular Volume
Hour Met?
Does the total entering volume serviced during the hour equal or exceed 650 vehicles per hour for intersection with three approaches or 800 vehicles per hour for intersections with four or more approaches?
Indicate whether all three of the following conditions for the same 1 hour (any four consecutive 15- minute periods) of an average day are present*
*If applicable, attach all supporting calculations and documentation.

Is this signal warrant being applied for an unusual case, such as office complexes, manufacturing plants, industrial complexes, or high-occupancy vehicle facilities that attract or discharge large numbers of vehicles over a short time? 6/2/2023 CAMUTCD Signal Warrants_Metro Air_I5NB_CumulativeNP.xlsm Metro Air Parkway at I-5 NB Ramps - Cumulative
MUTCD Warrant 3

Page 2 of 2 ends

Page 1 of 2 ends

Major Street: 2 or More Lanes
Minor Street: 2 or More Lanes
Yes
Yes
Yes
Yes
Total Number of Unique Hours Met
On Figure 4C-3
0 Hour Interval Major Street Combined Highest Minor Street Approach Beginning At Vehicles Per Hour (VPH) Vehicles Per Hour (VPH) 6:45 AM 682 161
7:00 AM 910 215
7:15 AM 683 162
7:30 AM 456 108
7:45 AM 228 54
8:00 AM 0 0
8:15 AM 0 0
8:30 AM 0 0
8:45 AM 0 0
9:00 AM 0 0
9:15 AM 0 0
1:30 PM 0 0
1:45 PM 0 0
2:00 PM 0 0
2:15 PM 0 0
2:30 PM 0 0
2:45 PM 0 0
3:00 PM 0 0
3:15 PM 0 0
3:30 PM 0 0
3:45 PM 0 0
4:00 PM 0 0
4:15 PM 101 21
4:30 PM 204 43
4:45 PM 307 65
5:00 PM 410 87
5:15 PM 309 66
5:30 PM 206 44
5:45 PM 103 22
6:00 PM 0 0
6:15 PM 0 0
6:30 PM 0 0
6:45 PM 0 0
Hour Met?
Does the total entering volume serviced during the hour equal or exceed 650 vehicles per hour for intersection with three approaches or 800 vehicles per hour for intersections with four or more approaches?
Indicate whether all three of the following conditions for the same 1 hour (any four consecutive 15- minute periods) of an average day are present*
*If applicable, attach all supporting calculations and documentation.

Is this signal warrant being applied for an unusual case, such as office complexes, manufacturing plants, industrial complexes, or high-occupancy vehicle facilities that attract or discharge large numbers of vehicles over a short time? Built-up Isolated Community With Less Than 10,000 Population or Above 40 MPH on Major Street?
MUTCD WARRANT 3, PEAK HOUR
Number of Lanes for Moving Traffic on Each
Approach
No
Hourly Vehicular Volume
Does the total stopped time delay experienced by the traffic on one minor-street approach (one direction only) controlled by a STOP sign equal or exceed 4 vehicle-hours for a one-lane approach or 5 vehicle-hours for a two-lane approach? Does the volume on the same minor-street approach (one direction only) equal or exceed 100 vehicles per hour for one moving lane of traffic or 150 vehicles per hour for two moving lanes?
6/2/2023 CAMUTCD Signal Warrants_Metro Air_I5SB_CumulativeNP.xlsm Metro Air Parkway at I-5 SB Ramps - Cumulative
MUTCD Warrant 3

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Page 1 of 2 ends

Major Street: 2 or More Lanes
Minor Street: 2 or More Lanes
Yes
Yes
Yes
Yes
Total Number of Unique Hours Met
On Figure 4C-3
2 Hour Interval Major Street Combined Highest Minor Street Approach Beginning At Vehicles Per Hour (VPH) Vehicles Per Hour (VPH) 6:45 AM 2080 262 Met
7:00 AM 2775 350 Met
7:15 AM 2082 263 Met
7:30 AM 1389 176
7:45 AM 695 88
8:00 AM 0 0
8:15 AM 0 0
8:30 AM 0 0
8:45 AM 0 0
9:00 AM 0 0
9:15 AM 0 0
1:30 PM 0 0
1:45 PM 0 0
2:00 PM 0 0
2:15 PM 0 0
2:30 PM 0 0
2:45 PM 0 0
3:00 PM 0 0
3:15 PM 0 0
3:30 PM 0 0
3:45 PM 0 0
4:00 PM 0 0
4:15 PM 735 41
4:30 PM 1470 82
4:45 PM 2205 123
5:00 PM 2940 165 Met
5:15 PM 2205 124
5:30 PM 1470 83
5:45 PM 735 42
6:00 PM 0 0
6:15 PM 0 0
6:30 PM 0 0
6:45 PM 0 0
Does the total stopped time delay experienced by the traffic on one minor-street approach (one direction only) controlled by a STOP sign equal or exceed 4 vehicle-hours for a one-lane approach or 5 vehicle-hours for a two-lane approach? Does the volume on the same minor-street approach (one direction only) equal or exceed 100 vehicles per hour for one moving lane of traffic or 150 vehicles per hour for two moving lanes?
Built-up Isolated Community With Less Than 10,000 Population or Above 40 MPH on Major Street?
MUTCD WARRANT 3, PEAK HOUR
Number of Lanes for Moving Traffic on Each
Approach
No
Hourly Vehicular Volume
Hour Met?
Does the total entering volume serviced during the hour equal or exceed 650 vehicles per hour for intersection with three approaches or 800 vehicles per hour for intersections with four or more approaches?
Indicate whether all three of the following conditions for the same 1 hour (any four consecutive 15- minute periods) of an average day are present*
*If applicable, attach all supporting calculations and documentation.

Is this signal warrant being applied for an unusual case, such as office complexes, manufacturing plants, industrial complexes, or high-occupancy vehicle facilities that attract or discharge large numbers of vehicles over a short time? 6/2/2023 CAMUTCD Signal Warrants_Metro Air_I5SB_CumulativeProject.xlsm Metro Air Parkway at I-5 SB Ramps - Cumulative w/ Project MUTCD Warrant 3

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APPENDIX O

TRIP GENERAT ION AND D ISTRIBUT ION MEMORANDUM
DATE: March 10, 2023
TO: Matthew Ilagan | City of Sacramento
Pelle Clarke | City of Sacramento
FROM: Sean Carney | DKS Associates
Dave Tokarski | DKS Associates
Vic Maslanka | DKS Associates
SUBJECT: Airport South Industrial – Phase B Project #19179-024 This memorandum summarizes the results of the trip generation and distribution analysis of the proposed Airport South Industrial project, based upon the latest Baseline Plus Project model runs.

The project consists of approximately 474.4 net acres of land to be annexed into the City of Sacramento and developed as M-1 (Industrial) and HC (Highway Commercial) zoning land uses.

PROJECT DESCRIPTION
As illustrated in Figure 1, the project is located on the south side of I-5 at the Metro Air Parkway interchange. Figure 2 illustrates the proposed site plan. Table 1 summarizes the land use utilized in the calculation of trip generation. This land use information was taken directly from the land use summary included in the project description information provided by the applicant to the City. The project includes over 6.6 million square feet of warehousing / distribution / industrial space, four restaurants, a fueling station / carwash, and a hotel.

A IRPORT SO UTH I ND USTRIA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 2 FIGURE 1: SITE LOCATION
A IRPORT SO UTH I ND USTRIA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 3 Source: Wood Rodgers, June 20, 2022.

FIGURE 2: PRELIMINARY SITE PLAN
A IRPORT SO UTH I ND US TR IA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 4 TABLE 1: LAND USE SUMMARY
Source: Wood Rodgers, June 20, 2022.

TRIP GENERATION ESTIMATION

INDUSTRIAL USES
For parcels 1 - 5, 8 – 11, and Caltrans, it was assumed that the parcels would be developed in a manner comparable to Metro Airpark (located on the north side of I-5). As the travel model utilizes “employees” as the land use variable, the building size was converted to number of employees. To calculate this conversion, the applicant provided information from comparable facilities throughout the United States, including the adjacent Metro Airpark. This information was reviewed by City staff, and an employment density of 0.572 employees per 1,000 square feet was assigned (one employee per 1,748 square feet). Table 2 summarizes the estimated number of employees for each parcel. A total of 3,781 employees were calculated.

Table 3 presents mode choice of the industrial uses for light vehicles. 96 percent of person trips are by automobile, 3 percent by walk mode, and 1 percent by bicycle. These estimates do not include heavy vehicle trips.

Table 4 summarizes the daily, AM peak hour, and PM peak hour vehicular trip generation of the industrial uses, as estimated by the travel model (Baseline Plus Project scenario). The industrial

PARCEL USE PARCEL SIZE (ACRES) BUILDING SIZE
(SQUARE FEET)
1 - 5 Warehouse Distribution 235.6 5,204,500
6A Restaurant 2.1 3,900
6B Restaurant 1.5 3,900
6C Fueling Station /
Carwash 3.0 8,100
7A Hotel 4.0 73,400
7B Restaurant 1.5 3,900
7C Restaurant 1.3 5,000
8-11 AND CALTRANS Future Industrial 83.0 1,404,800
A IRPORT SO UTH I ND US TR IA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 5 uses are estimated to generate 12,794 daily trips, 1,191 AM peak hour trips, and 1,004 PM peak hour trips. This includes light vehicle and heavy vehicle trips.

TABLE 2: INDUSTRIAL EMPLOYMENT SUMMARY
TABLE 3: INDUSTRIAL DAILY MODE CHOICE

PARCEL PARCEL SIZE (ACRES) BUILDING SIZE
(SQUARE FEET) EMPLOYEES
1 47.7 979,400 560
2 53.4 1,335,200 764
3 34.4 772,900 442
4 54.7 1,335,200 764
5 45.4 781,800 447
8 64.3 1,088,200 622
9 6.5 110,000 63
10 4.6 77,900 45
11 0.7 11,900 7
CALTRANS 6.9 116,800 67
INDUSTRIAL SUMMARY 318.6 6,609,300 3,781

MODE PERCENTAGE OF PERSON TRIPS
WALK 3%
BICYCLE 1%
AUTOMOBILE – 1 OCCUPANT (SOV) 71%
AUTOMOBILE – 2 OCCUPANTS (HOV2) 14%
AUTOMOBILE – 3 OR MORE OCCUPANTS (HOV3+) 11%
A IRPORT SO UTH I ND US TR IA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 6 TABLE 4: ESTIMATED INDUSTRIAL TOTAL TRIP GENERATION
Table 5 compares the total vehicle trip generation rates of the travel model (trips per 1,000 square feet) to ITE Trip Generation1, rates for similar land uses. The travel model estimates are similar to the ITE warehouse rates (model is higher for daily and AM peak hour, lower for PM peak hour), but lower than light industrial and manufacturing uses. The model projections are consistent with the warehousing and fulfillment center uses that predominate the Metro Airpark.

No further adjustments to the travel model for industrial total trip generation purposes are recommended.

Table 6 summarizes the heavy vehicle trip generation estimates of the travel model. Compared to the anticipated heavy vehicle trip generation for these industrial uses, these estimates are low.

Table 7 compares the heavy vehicle trip percentages to ITE Trip Generation percentages for similar land uses, as well as data from Metro Airpark.

It is recommended that the heavy vehicle trip generation rates should be increased, and applied with a post-processor methodology to adjust the model estimates to reflect anticipated heavy vehicle travel volumes. Based upon the ITE Trip Generation data and the data from Metro Airpark, the recommended heavy vehicle trip generation estimates are presented in Table 8. 1 11th Edition, Version 6.0.1, May 2022

TOTAL VEHICLE TRIPS (LIGHT VEHICLES AND HEAVY VEHICLES) DAILY

AM PEAK HOUR PM PEAK HOUR

ENTER EXIT TOTAL ENTER EXIT TOTAL
12,794 886 305 1,191 281 723 1,004
A IRPORT SO UTH I ND US TR IA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 7 TABLE 5: COMPARISON TO ITE AND METRO AIRPARK INDUSTRIAL TRIP GENERATION RATES a. Metro Air Park – Lot 49 Site Access and Circulation Analysis Update, Fehr & Peers, March 22, 2021. b. Project Bronco – Metro Air Parkway / Skyking Road Existing Plus Project and Existing Plus Project Plus Building 1 Signal Warrant Analysis, Fehr & Peers, September 14, 2020. c. 8035 Metro Air Parkway – Site Access and Circulation Analysis Update, Fehr & Peers, August 3, 2021. d. Metro Air Parkway / I-5 Interchange PS&E Support – Part 2, Fehr & Peers, August 4, 2017.

ITE

CODE LAND USE
VEHICLE TRIPS PER 1,000 SQUARE FEET

DAILY AM PEAK HOUR PM PEAK HOUR
Travel Model Estimates 1.94 0.18 0.15
110 General Light Industrial 4.87 0.74 0.65
130 Industrial Park 3.37 0.34 0.34
140 Manufacturing 4.75 0.68 0.74
150 Warehousing 1.71 0.17 0.18
154
High-Cube Transload and Short-Term
Storage Warehouse 1.40 0.08 0.10
155
High-Cube Fulfillment Center Warehouse -
Non-Sort 1.81 0.15 0.16
-
Amazon SMF5 (Metro Airpark) – Peak
Seasona 7.43 0.93 0.82
-
Amazon SMF5 (Metro Airpark) – Off-Peak
Seasona 4.46 0.56 0.49
- Walmart SMF1 (Metro Airpark)b

0.31 0.12 0.12
- SC Johnson (Metro Air Park)b

0.58 0.07 0.06
- 8035 Metro Air Parkwayc - 0.61 0.61
- Amazon Fulfillment Center, Patterson, CAd

1.80 0.08 0.36
- JC Penney Distribution Center, Lathrop, CAd

0.70 0.03 0.04
A IRPORT SO UTH I ND US TR IA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 8 TABLE 6: ESTIMATED INDUSTRIAL HEAVY VEHICLE TRIP GENERATION

VEHICLE TRIPS

VEHICLE

TYPE DAILY

AM PEAK HOUR PM PEAK HOUR

ENTER EXIT TOTAL ENTER EXIT TOTAL
HEAVY 536 26 26 52 9 9 18
TOTAL 12,794 886 305 1,191 281 723 1,004

PERCENT
HEAVY
TRIPS
4% 3% 9% 4% 3% 1% 2%
A IRPORT SO UTH I ND US TR IA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 9 TABLE 7: COMPARISON TO ITE AND METRO AIRPARK INDUSTRIAL HEAVY VEHICLE TRIP

PERCENTAGES
a. Metro Air Park – Lot 49 Site Access and Circulation Analysis Update, Fehr & Peers, March 22, 2021. b. Project Bronco – Metro Air Parkway / Skyking Road Existing Plus Project and Existing Plus Project Plus Building 1 Signal Warrant Analysis, Fehr & Peers, September 14, 2020. c. 8035 Metro Air Parkway – Site Access and Circulation Analysis Update, Fehr & Peers, August 3, 2021.

ITE

CODE LAND USE

PERCENT HEAVY TRIPS
DAILY
AM
PEAK
HOUR
PM
PEAK
HOUR
Travel Model Estimates 4% 4% 2%
110 General Light Industrial 5% 1% 2%
130 Industrial Park 17% 12% 12%
140 Manufacturing 9% 4% 4%
150 Warehousing 35% 12% 17%
154 High-Cube Transload and Short-Term Storage Warehouse 16% 25% 10% 155 High-Cube Fulfillment Center Warehouse - Non-Sort 13% 13% 6% - Amazon SMF5 (Metro Airpark) – Peak Seasona
23% 7% 13%
- Amazon SMF5 (Metro Airpark) – Off-Peak Seasona
23% 7% 13%
- Walmart SMF1 (Metro Airpark)b
22% 2% 2%
- SC Johnson (Metro Air Park)b
77% 100% 100%
- 8035 Metro Air Parkwayc - 4% 3%
A IRPORT SO UTH I ND US TR IA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 10 TABLE 8: RECOMMENDED INDUSTRIAL HEAVY VEHICLE TRIP GENERATION

HIGHWAY COMMERCIAL USES
Similar to the industrial uses, the building sizes of the highway commercial uses were converted to employees for input to the travel model. Consistent with other retail and service uses in the travel model, 500 square feet per employee was assumed. This yields 33 employees for the land use west of Metro Air Parkway, and 164 employees for the land use east of Metro Air Parkway.

Table 9 presents mode choice of the highway commercial uses. 97 percent of person trips are by automobile, 3 percent by walk mode, and less than 1 percent by bicycle. The number of heavy vehicle trips associated with the highway commercial uses are small, unless a truck-oriented business is developed within this area.

TABLE 9: HIGHWAY COMMERCIAL DAILY MODE CHOICE
Table 10 summarizes the highway commercial vehicle trip generation estimates of the travel model.

VEHICLE TRIPS

VEHICLE

TYPE DAILY

AM PEAK HOUR PM PEAK HOUR

ENTER EXIT TOTAL ENTER EXIT TOTAL
HEAVY 2,559 89 31 119 28 72 100
TOTAL 12,794 886 305 1,191 281 723 1,004

PERCENT
HEAVY
TRIPS
20% 10% 10% 10% 10% 10% 10%

MODE PERCENTAGE OF PERSON TRIPS
WALK 3%
BICYCLE <1%
AUTOMOBILE – 1 OCCUPANT (SOV) 57%
AUTOMOBILE – 2 OCCUPANTS (HOV2) 23%
AUTOMOBILE – 3 OR MORE OCCUPANTS (HOV3+) 17%
A IRPORT SO UTH I ND US TR IA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 11 TABLE 10: ESTIMATED HIGHWAY COMMERCIAL TRIP GENERATION
Compared to the anticipated trip generation for these highway commercial uses adjacent to an interstate freeway, these estimates are extremely low. The travel model does not include land use categories / uses specific to intense highway commercial uses, such as a convenience store / gas station. The model trip generation is also unconstrained for employment uses, which reduces the number of trips attracted to a land use not adjacent to a developed area.

It is recommended that ITE trip generation rates be used for the highway commercial uses, and applied with a post-processor methodology to adjust the model estimates to reflect anticipated travel volumes. This is especially critical for the access management review along Metro Air Parkway near the I-5 interchange, and along Airport South Industrial Drive.

The recommended trip generation of the highway commercial uses is based upon representative uses from the Institute of Transportation Engineers (ITE) Trip Generation Manual 11th Edition, Version 6.0.1, May 2022. Table 11 summarizes the land use on each parcel and the assumed ITE land use code and statistics.

Table 12 and Table 13 summarize the vehicle trip generation estimates for the highway commercial parcels. Parcel 6C was calculated based upon both fueling positions and convenience store size, with the results averaged. Pass-by percentages are based upon ITE data. Internal trips are limited to a maximum of 10 percent, with no trips assumed between restaurants. The appendix includes the trip generation calculations for highway commercial uses.

PARCEL EMPLOYEES

VEHICLE TRIPS
DAILY

AM PEAK HOUR PM PEAK HOUR

ENTER EXIT TOTAL ENTER EXIT TOTAL
6A, 6B, 6C
(WEST) 33 298 15 5 20 9 15 23
7A, 7B, 7C
(EAST) 164 1,005 54 18 73 24 48 72

HIGHWAY

COMMERCIAL

SUMMARY
197 1,303 69 23 93 33 63 95
A IRPORT SO UTH I ND US TR IA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 12 TABLE 11: HIGHWAY COMMERCIAL PARCEL TRIP GENERATION CHARACTERISTICS

PARCEL PROPOSED

USE ACRES SQUARE FEET
ITE
CODE

ASSUMED

USE ASSUMPTIONS
6A Restaurant 2.1 3,900 934 Fast-Food
Restaurant
With DriveThrough
-
6B Restaurant 1.5 3,900 934 -
6C
Fueling
Station /
Carwash

3.0 8,100 945
Convenience
Store / Gas
Station
8,100 square-foot convenience
store, 20 fueling positions
7A Hotel 4.0 73,400 310 Hotel 122 Rooms, based on typical 600 square feet per room
7B Restaurant 1.5 3,900 934 Fast-Food
Restaurant
With DriveThrough
-
7C Restaurant 1.3 5,000 934 -
A IRPORT SO UTH I ND US TR IA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 13 TABLE 12: HIGHWAY COMMERCIAL VEHICLE TRIP GENERATION ESTIMATES – WEST PARCELS

PARCEL PROPOSED USE

VEHICLE TRIPS (INCLUDES TRUCK TRIPS)
DAILY

AM PEAK HOUR PM PEAK HOUR

ENTER EXIT TOTAL ENTER EXIT TOTAL

TOTAL TRIPS
6A Restaurant 1,823 89 85 174 67 62 129
6B Restaurant 1,823 89 85 174 67 62 129
6C Fueling Station /
Carwash 8,655 343 343 686 295 294 589
Total 12,301 521 513 1,034 429 418 847

INTERNAL TRIPS
Total -729 -35 -35 -70 -26 -26 -52

PASS-BY TRIPS
6A Restaurant -861 -40 -38 -78 -33 -31 -64
6B Restaurant -861 -40 -38 -78 -33 -31 -64
6C Fueling Station /
Carwash -6,259 -247 -248 -495 -211 -211 -422
Total -7,982 -327 -324 -652 -278 -273 -550

NEW TRIPS
6A Restaurant 779 40 38 78 27 25 52
6B Restaurant 779 40 38 78 27 25 52
6C Fueling Station /
Carwash 2,031 78 78 156 70 70 141
Total 3,590 158 155 313 125 121 245
A IRPORT SO UTH I ND US TR IA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 14 TABLE 13: HIGHWAY COMMERCIAL VEHICLE TRIP GENERATION ESTIMATES – EAST PARCELS

PARCEL PROPOSED USE

VEHICLE TRIPS (INCLUDES TRUCK TRIPS)
DAILY

AM PEAK HOUR PM PEAK HOUR

ENTER EXIT TOTAL ENTER EXIT TOTAL

TOTAL TRIPS
7B Restaurant 1,823 89 85 174 67 62 129
7C Restaurant 2,337 114 109 223 86 79 165
7A Hotel 975 31 25 56 37 35 72
Total 5,135 234 219 453 190 176 366

INTERNAL TRIPS
Total -195 -6 -5 -11 -7 -7 -14

PASS-BY TRIPS
7B Restaurant -935 -44 -42 -86 -36 -33 -69
7C Restaurant -1,198 -56 -54 -110 -46 -42 -89
7A Hotel 0 0 0 0 0 0 0
Total -2,133 -100 -96 -196 -82 -76 -158

NEW TRIPS
7B Restaurant 846 44 42 86 29 27 57
7C Restaurant 1,084 56 54 110 38 35 72
7A Hotel 878 28 23 50 33 32 65
Total 2,807 128 118 246 100 93 194
A IRPORT SO UTH I ND US TR IA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 15

TRIP DISTRIBUTION ESTIMATES

INDUSTRIAL USES
Figure 3 illustrates the project trip distribution from the Baseline Plus Project scenario for the industrial uses. Separate distribution percentages are displayed for light vehicles (automobiles) and heavy vehicles.

FIGURE 3: BASELINE PROJECT TRIP DISTRIBUTION FOR INDUSTRIAL USES A IRPORT SO UTH I ND US TR IA L • TRI P GE NERATION MEMORA ND UM • MARCH 10 , 2023 16

HIGHWAY COMMERCIAL USES
Figure 4 illustrates the project trip distribution from the Baseline Plus Project scenario for the highway commercial uses. As discussed previously, these uses will not generate a large volume of heavy vehicles. The distribution reflects new trips. Pass-by trips associated with the highway commercial uses will primarily be associated with traffic patterns on I-5.

FIGURE 4: BASELINE PROJECT TRIP DISTRIBUTION FOR HIGHWAY COMMERCIAL USES

APPENDIX P

DRAFT VMT ANALYS IS
DATE: March 10, 2023
TO: Matthew Ilagan, Pelle Clarke | City of Sacramento
FROM: Sean Carney, David Tokarski, Vic Maslanka | DKS Associates SUBJECT: Airport South Industrial VMT Analysis Project #19179-024

INTRODUCTION
In accordance with Senate Bill 743 (SB 743) and the resulting changes to the California Environmental Quality Act (CEQA) Guidelines published by the Natural Resources Agency, local agencies may no longer use measures of vehicle delay such as Level of Service (LOS) to quantify transportation impacts on the environment. VMT is a systemic metric and is a useful indicator of overall land use and transportation efficiency, where the most efficient system is one that minimizes VMT by encouraging shorter vehicle trip lengths, more walking and biking, or increased carpooling and transit. Vehicle miles traveled (VMT) has been codified in the CEQA Guidelines as the most appropriate measure for measuring transportation impacts under CEQA. This change went into effect statewide on July 1, 2020. The City of Sacramento’s draft transportation impact guidelines are consistent with OPR’s recommendation of using VMT as a metric.

INDUSTRIAL USES
Based on current practice of the City of Sacramento, transportation impacts are considered significant if the proposed project would result in a VMT per capita or office VMT per employee above 85% of the regional average, consistent with technical guidance published by the Governor’s Office of Planning and Research (OPR). The OPR guidance does not specify a particular significance threshold for industrial employment and recommends that local jurisdictions determine this threshold based on local conditions. Some jurisdictions in the Sacramento region (including Sacramento County (adopted) and the City of Rancho Cordova (adopted)) have determined that the significance threshold for industrial employment is 100% of regional average. The reasoning for this less restrictive threshold for industrial uses compared to other employment types is rooted in improving overall VMT efficiency of all future development in aggregate. Industrial uses generally have more zoning restrictions and are generally less densely developed than other employment types making them less desirable within urban areas. By keeping these uses outside of urban centers, the land that they would occupy can instead be used for higher density land development that can see a greater benefit from being located in VMT efficient areas. This inherently means industrial uses will have higher VMT per employee than other employment types because they are A IRPORT SO UTH I ND US TR IA L • VMT A NA LYS IS • MARCH 10 , 2023 2 located further from a good mix of housing and services which are necessary to achieve lower VMT levels. The draft City of Sacramento Transportation Impact Analysis Guidelines do not specify a significance threshold for industrial land uses. For consistency with other nearby jurisdictions and after discussion with City staff, this analysis applies the significance threshold of 100% of regional average for industrial uses.

HIGHWAY COMMERCIAL USES
Because new retail development often redistributes trips rather than creating new travel demand, the OPR guidance recommends that lead agencies analyze the net change in VMT to indicate the transportation impact of retail projects.1
The potential for VMT impacts, according to this approach, hinges on whether the project can be considered local-serving or regional. By adding retail opportunities within existing neighborhoods, local-serving retail projects can shorten trips and reduce overall VMT. In contrast, regional destination retail projects would draw customers from larger trade areas, potentially substituting for shorter trips and increasing VMT. The OPR guidance suggests that any retail projects including stores larger than 50,000 square feet might be considered regional serving retail.

This approach has been applied to the highway commercial uses. As discussed below, the individual uses were reviewed to determine whether they can be considered regional “destination” uses which would attract vehicle trips from a large area and potentially increase VMT, or whether the uses duplicate other existing projects in the nearby area and could reduce VMT.

VMT SCREENING

VMT SCREENING CRITERIA
Pursuant to SB 743 and technical guidance published by OPR, there are several screening procedures to potentially streamline project analysis (i.e., provide a presumptive non-impact finding and obviate the need for a VMT analysis). The various screening options are listed below with a brief determination of whether a given screen is triggered by the proposed project.  Project Size: Projects that generate fewer than 110 trips per day can be presumed to have a less than significant transportation impact. Based on the trip generation data presented in the Transportation Analysis (in a separate document prepared by DKS), the proposed project does not meet this screening criteria.
 Proximity to High Quality Transit: Residential or office projects within one-half mile of an existing major transit station or stop along an existing high-quality transit corridor can be 1 Governor’s Office of Planning and Research, Technical Advisory on Evaluating Transportation Impacts in CEQA. (New York: Free Press, December 2018), 15–16.

A IRPORT SO UTH I ND US TR IA L • VMT A NA LYS IS • MARCH 10 , 2023 3 presumed to have a less than significant transportation impact. The proposed project is not currently served by transit. The project does not meet this screening criteria.  Affordable Housing Development: The proposed project does not include the provision of housing. The proposed project does not meet this screening criteria.  Locally Serving Retail: Typically less than 50,000 square feet. The Highway Commercial component of the project could potentially meet this screening criteria, as discussed below.  Infrastructure: Projects that would not likely lead to a substantial or measurable increase in vehicle travel are presumed to be VMT neutral and generally presumed to have a less than significant transportation impact (i.e., induced VMT). These include: Roadway Maintenance and Rehab Projects; Signal Timing / Synchronization / Adaptive Signal Control /Signal Preemption Improvements; Intersection Control Type and Turn Lane Channelization Improvements; Widening for Local or Local Collector Streets; and Transit / Bicycle / Pedestrian Infrastructure Improvements. The proposed project does not contain any substantial infrastructure improvements that meet this screening criteria.
 Project Location: Projects that fall within an identified location (in this case SACOG’s hexagon methodology is used for screening purposes) that demonstrates VMT per Capita for residential projects below 85% of the regional average for that metric, or VMT per Employee for employment-based projects below 100% of the regional average for that metric. As discussed below, the industrial portion of the project does not meet this screening criteria.

INDUSTRIAL VMT ANALYSIS

VMT EMPLOYMENT SCREENING MAP
Figure 1 illustrates SACOG’s VMT Employment Screening Map for the project vicinity. As the hexagons are based upon 2016 conditions, and the project site was vacant, there are no applicable hexagons that apply to the entirety of the project. On the northeast corner of the project site, the hexagon which includes the northwest (employment) corner of Westlake, the VMT per employee is shown as 103% of the regional average.

A IRPORT SO UTH I ND US TR IA L • VMT A NA LYS IS • MARCH 10 , 2023 4 FIGURE 1: VMT EMPLOYMENT SCREENING MAP
Near the northwest corner of the project site, several hexagons are located at and adjacent to Sacramento International Airport. The VMT per employee is shown as 178% of the regional average. The SACOG screening map does not provide information for most of Metro Airpark, as the calculations are based upon 2016 conditions. Based upon this information, the industrial portion of the project does not meet the screening criteria.

TRAVEL DEMAND MODEL ANALYSIS

TRAVEL DEMAND MODEL
The CEQA VMT analysis is based on the latest SACOG SACSIM-19 activity-based travel demand model (ABM) including scripts prepared by SACOG for this very analysis purpose. The analysis is tour‐based, meaning that the analysis fully accounts for trips that are linked to trips that start or end at the project. This means that intermediate trips, such as those occurring after someone has left the project area, such as a trip to pick‐up lunch while at work, are accounted for in this analysis.

Based on the latest SACOG model scripts, SACSIM-19 also reflects the entire trip length, including the portion of the trip that occurs outside the SACOG region. External‐internal and internal‐external A IRPORT SO UTH I ND US TR IA L • VMT A NA LYS IS • MARCH 10 , 2023 5 VMT is calculated via a script file provided by SACOG and included in their model for VMT post‐processing. The post-processor determines the added VMT that occurs outside the SACOG region (i.e., for trips that either start or end outside of the region). This interregional VMT is then added to the internal-internal VMT to determine the total VMT. Consistent with OPR guidelines, only automobile trips are considered as a part of this analysis. Heavy-duty truck and delivery vehicle VMT as well as alternative mode VMT (transit vehicles) are not reflected.

PROJECT USE (VMT PER EMPLOYEE METRIC)
For work-based land uses of the proposed project, SACSIM-19 was used with a modified version of the SACOG script to meet guidance from the Office of Planning and Research (OPR) as previously discussed. A regional baseline (2016) average VMT per employee metric was used to establish the threshold set at 100% of the regional average.

For the industrial portion of the project, the average VMT is calculated as 128% of the regional average.

HIGHWAY COMMERCIAL VMT ANALYSIS
The highway commercial area of the project includes the uses shown in Table 1.

A IRPORT SO UTH I ND US TR IA L • VMT A NA LYS IS • MARCH 10 , 2023 6 TABLE 1: HIGHWAY COMMERCIAL LAND USE SUMMARY
Source: Wood Rodgers, June 20, 2022.
 The proposed uses are ubiquitous throughout the area, with many competitors at nearby I-5 interchanges (Del Paso Road and Arena Boulevard). This includes restaurants, fueling stations, carwashes, convenience stores, and hotels.
 The highway commercial uses would serve travelers and employees associated with Sacramento International Airport. These trips could reduce VMT by potentially diverting a trip from a destination located farther from the airport.
 The highway commercial uses would also serve the industrial uses of the project, as well as the development of Metro Airpark. These trips could reduce VMT by potentially diverting a trip from a destination located farther from the project and Metro Airpark.  With the exception of the hotel, all of the projects are less than 50,000 square feet, which is a “rule of thumb” for VMT screening of retail projects.

VMT IMPACT

INDUSTRIAL USES
The travel model VMT analysis estimates the average VMT of the industrial uses as 128% of the regional average. This is a significant impact.

HIGHWAY COMMERCIAL USES
Based upon the nature of the highway commercial uses, it is concluded that the highway commercial uses meet the retail screening criteria. This is a less-than-significant impact.

PARCEL USE PARCEL SIZE (ACRES) BUILDING SIZE
(SQUARE FEET)
6A Restaurant 2.1 3,900
6B Restaurant 1.5 3,900
6C Fueling Station /
Carwash 3.0 8,100
7A Hotel 4.0 73,400
7B Restaurant 1.5 3,900
7C Restaurant 1.3 5,000

APPENDIX Q
Acknowledgement & Conflict of Interest

Page 1 of 1 ends

DRAFT MEMORANDUM
DATE: September 26, 2023
TO: Pelle Clarke, Senior Engineer
FROM: Daniel S. Cucchi, Attorney for Applicant
CC: Nick S. Avdis, Attorney for Applicant
SUBJECT: P21-017 Airport South Industrial - VMT Mitigation Measures I. Introduction & Background
The intent of this memo is to outline the P21-017 Airport South Industrial Vehicle Miles Traveled (VMT) mitigation approach and corresponding calculations for the project. The project proposes to develop approximately 470 acres of vacant land for industrial and commercial uses in North Natomas that would be annexed into the City of Sacramento. The project is located south of I-5 and west of the Westlake community. The proposed project would connect to the I-5 Metro Air Parkway interchange as well as Powerline Road to the west and Bayou Way to the east.

Per the DKS Draft VMT Analysis dated March 10, 2023, the proposed project would result in an average VMT calculated as 128% of the regional average and is considered a significant impact. Since the Office of Planning and Research (OPR) does not specify a particular significance threshold for industrial employment, OPR recommends local jurisdictions to determine this threshold based on local conditions.

Local jurisdictions in the region such as Sacramento County and City of Rancho Cordova have determined the significance threshold for industrial employment as 100% of regional average.

Consistent with nearby jurisdictions, the City has established the significance threshold of 100% of regional average for industrial uses. With the 100% significance threshold, the project is required to mitigate 22% (1-1.00/1.28 = 0.22) to achieve a less-than significant impact for VMT. Consistent with SB 743, OPR’s Technical Advisory, and California Air Pollution Control Officers Association (CAPCOA), the proposed project is required to mitigate VMT utilizing CAPCOA’s Handbook for Analyzing Greenhouse Gas Emission Reductions, Assessing Climate Vulnerabilities, and Advancing Health and Equity dated December 2021 (CAPCOA 2021 Handbook).

The applicant iproposes a mitigation measure which allows for the owner/operator of a building (or set of buildings) within the project site, prior to the issuance of a certificate of occupancy, to submit and receive City approval of a VMT Reduction Plan that includes a commitment to implement a selection of VMT reduction strategies (listed below) from the CAPCOA 2021 Handbook, totaling at or more than a 22% reduction in VMT for the covered building sites. The proposed VMT reduction plan must comply with the CAPCOA rules to prevent double-counting, and provide documentation calculating the VMT reduction value of each adopted measure as applied to the specific building site(s) and operations.

VMT Reduction Plan Memo
September 26, 2023

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II. CAPCOA Transportation Quantitative GHG Reduction Measures CAPCOA’s 2021 Handbook outlines the quantitative reduction measures that can be used to mitigate VMT impacts. There are 6 categories within the Transportation section with corresponding subsections for quantifying VMT mitigation measures.

Below are the 6 categories:

1. Land Use

2. Trip Reduction Programs

3. Parking or Road Pricing/Management

4. Neighborhood Design

5. Transit

6. Clean Vehicles and Fuels
Given the largely industrial and highway commercial nature of the project and no existing or planned transit within the project’s vicinity, all but the Trip Reduction Programs category can be eliminated when identifying applicable VMT mitigation measures for the project. Below are mitigation options within the Trip Reduction Programs category with its subsequent maximum percentages to reduce VMT, as calculated below in this memorandum:
• T-6 Implement Commute Trip Reduction Program (Mandatory Implementation & Monitoring) – 26% • T-7 Implement Commute Trip Reduction Marketing – 4%
• T-8 Provide Ridesharing Program – 8%
• T-9 Implement Subsidized or Discounted Transit Program – 1.2% • T-10 Provide End-of-Trip Bicycle Facilities – 2.5%
• T-11 Provide Employer-Sponsored Vanpool – 1.4%
• T-12 Price Workplace Parking – 20%
• T-13 Implement Employee Parking Cash-Out – 12%
While the Trip Reduction Programs category allows for mitigating VMT up to a maximum of 45%, it also identifies additional limitations for quantifying the mitigation percentages to reduce VMT. Each subsector of mitigation options identifies how some mitigation options have mutually exclusive measures, as well as expanded mitigation options. The mutually exclusive measures identify which measures cannot be credited together as it would be considered double counting.

III. Limitations to Avoid Double-Counting
As identified in CAPCOA’s 2021 Handbook, T-6 requires the implementation of a Commute Trip Reduction (CTR) Program that allows for a maximum of 26% for mitigating VMT. Within the implementation requirements, it explicitly outlines T-7 through T-11 cannot be used with this option.

The mandatory CTR includes T-7 through T-11 and therefore cannot be added if T-6 is used. The VMT Reduction Plan Memo
September 26, 2023

Page 3 of 8 ends

expanded mitigation options for T-6 are identified to be T-12 or T-13 (cannot be both). Below is a list of implementation requirements for T-7 through T-11:
• T-7 Implement Commute Trip Reduction Marketing
o Onsite or online commuter information services
o Employee transportation coordinators
o Onsite or online transit pass sales
o Guaranteed ride home services
• T-8 Provide Ridesharing Program
o Ridesharing must be promoted through a multifaceted approach o Designating a certain percentage of desirable parking spaces for ridesharing vehicles o Designating adequate passenger loading and unloading and waiting areas for ridesharing vehicles
o Providing an app or website for coordinating rides
• T-9 Implement Subsidized or Discounted Transit Program o The project should be accessible either within 1 mile of high-quality transit service, 0.5 mile of local or less frequent transit service, or along a designated shuttle route providing last-mile connections to rail service
• T-10 Provide End-of-Trip Bicycle Facilities
o End-of trip facilities should be installed at a size proportional to the number of commuting bicyclists and regularly maintained
• T-11 Provide Employer-Sponsored Vanpool
o Vanpool programs are more appropriate for the building occupant or tenant to implement and monitor than the building owner or developer Thus, an operator may select T-6, but cannot also select any of T-7 through T-11. Furthermore, an operator cannot select both T-12 and T-13, regardless of whether they select T-6, or one or more of T-7 through T-11.

IV. Sample Calculations For Trip Reduction Programs T-6 Through T-13 GHG Calculations for T-6
Following the GHG formula and variables for T-6, the following calculations are provided below with representation of the corresponding variables:

GHG Reduction Formula: 𝐴 = 𝐵 𝑥 𝐶 𝑥 𝐷
ID Variable Value Unit Source
A Percent reduction in GHG emissions from
project/site employee commute VMT
0 – 26.0 % calculated
B Percent of employees eligible for program 0 – 100 % User input C Percent reduction in vehicle mode share in
employee commute trips
-26 % Nelson\Nygaard Consulting
Associates 2015
D Adjustment from vehicle mode share to
commute VMT
1 unitless assumed
VMT Reduction Plan Memo
September 26, 2023

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𝐴 = 1 𝑥 (−0.26) 𝑥 1 = −𝟐6%
With the recommendation in CAPCOA for 100% for variable B, the resulting maximum percentage for reduction is -26% for mitigating VMT.

GHG Calculations for T-7
Following the GHG formula and variables for T-7, the following calculations are provided below with representation of the corresponding variables:

GHG Reduction Formula: 𝐴 = 𝐵 𝑥 𝐶 𝑥 𝐷
ID Variable Value Unit Source
A Percent reduction in GHG emissions from
project/site employee commute VMT
0 – 4.0 % calculated
B Percent of employees eligible for program 0 – 100 % User input C Percent reduction in employee
commute vehicle trips
-4 % TRB 2010
D Adjustment from vehicle trips to VMT 1 unitless assumed 𝐴 = 1 𝑥 (−0.04) 𝑥 1 = −4%
With the recommendation in CAPCOA for 100% for variable B, the resulting maximum percentage for reduction is -4% for mitigating VMT.

GHG Calculations for T-8
Following the GHG formula and variables for T-8, the following calculations are provided below with representation of the corresponding variables:

GHG Reduction Formula: 𝐴 = 𝐵 𝑥 𝐶
ID Variable Value Unit Source
A Percent reduction in GHG emissions from
project/site employee commute VMT
0 – 8.0 % calculated
B Percent of employees eligible for program 0 – 100 % User input C Percent reduction in employee
commute VMT
-8
(Urban)
% SANDAG 2015
𝐴 = 1 𝑥 (−0.08) 𝑥 1 = −8%
With the recommendation in CAPCOA for 100% for variable B, the resulting maximum percentage for reduction is -8% for mitigating VMT.

VMT Reduction Plan Memo
September 26, 2023

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GHG Calculations for T-9
Following the GHG formula and variables for T-9, the following calculations are provided below with representation of the corresponding variables:

GHG Reduction Formula: 𝐴= (C/B) 𝑥 G 𝑥 𝐷 x E x F x H x I ID Variable Value Unit Source
A Percent reduction in GHG emissions from
employee vehicles accessing the site
0 – 5.5 % calculated
B Average transit fare without subsidy $100/mo. $ User input C Subsidy Amount $100/mo. $ User input
D Percent of employees eligible for subsidy 0 – 100 % User input E Percent of project-generated VMT
from employees
0 – 100 % User input
F Transit mode share of work trips 5.44%
(Table T-9.1)
% FHWA 2017
G Elasticity of transit boardings with
respect to transit fare price
-0.43 unitless Taylor et al. 2008
H Percent of transit trips that would
otherwise be made in a vehicle
50 % Handy & Boarnet 2013
I Conversion factor of vehicle trips to VMT 1 unitless assumption 𝐴 = (100/100 𝑥 -0.43) 𝑥 1 x 1 x 0.0544 x 0.50 x I
With the recommendation in CAPCOA for 100% for variables D and E, the resulting maximum percentage for reduction is -1.2% for mitigating VMT.

VMT Reduction Plan Memo
September 26, 2023

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GHG Calculations for T-10
Following the GHG formula and variables for T-10, the following calculations are provided below with representation of the corresponding variables:

GHG Reduction Formula: 𝐴 = [C x (E – (B x E))] / (𝐷 x F) ID Variable Value Unit Source
A Percent reduction in GHG emissions from
employee project/site commute VMT
0 .1 – 4.4 % calculated
B Bike mode adjustment factor 1.78 or

4.86 % Buehler 2012
C Existing bicycle trip length
for all trips in region

2.9 miles FHWA 2017a
D Existing vehicle trip length
for all trips in region

10.9 miles FHWA 2017a
E Existing bicycle mode share for
work trips in region

2.2 % FHWA 2017b
F Existing vehicle mode share for
work trips in region

89.5 % FHWA 2017b
𝐴 = [(2.9 𝑥 (.022 – (4.86 x .022))] / (10.9 𝑥 .895) = −𝟐.5% The resulting maximum percentage for reduction is -2.5% for mitigating VMT (assuming facilities include bike parking, showers, and lockers).

GHG Calculations for T-11
Following the GHG formula and variables for T-11, the following calculations are provided below with representation of the corresponding variables:

GHG Reduction Formula: 𝐴 = (((1 – 𝐵) 𝑥 𝐶) + (B x (D / E)) / C) - 1 ID Variable Value Unit Source
A Percent reduction in project/site
employee commute VMT

3.4 – 20.4 % calculated
B Percent of employees that participate
in van pool program

2.7 % SANDAG 2019
C Average length of one-way vehicle
commute trip in region

14.23 miles per
trip
FHWA 2017
D Average length of one-way
vanpool commute trip
42 miles per
trip
SANDAG 2019
E Average vanpool occupancy
(including driver)

6.25 occupants SANDAG 2019
𝐴 = (((1 – .027) x 14.23) + (.027 𝑥 (42 / 6.25)) / 14.23) – 1 = −1.4% The resulting maximum percentage for reduction is -1.4% for mitigating VMT.

VMT Reduction Plan Memo
September 26, 2023

Page 7 of 8 ends

GHG Calculations for T-12
Following the GHG formula and variables for T-12, the following calculations are provided below with representation of the corresponding variables:

GHG Reduction Formula: 𝐴 = ((𝐵 – C) / C) 𝑥 E 𝑥 𝐷 x F
ID Variable Value Unit Source
A Percent reduction in GHG emissions
from employee commute VMT
0 – 20.0 % calculated
B Proposed parking price 100/mo $ user input
C Baseline parking price 0 $ user input
D Share of employees paying for parking 100 % user input E Elasticity of parking demand with respecting
to parking price
-0.4 unitless Lehner & Peer 2019
F Ratio of vehicle trip reduction to VMT 1 unitless assumption 𝐴 = .50 𝑥 -0.4 𝑥 1 x 1 = −𝟐0%
Because the maximum allowed price increase of 50% is lower than the maximum increase for a new build project which by definition is 100%, the formula replaces the price increase calculation ([B – C] / C), with 50%. The resulting maximum percentage for reduction is -20% for mitigating VMT.

GHG Calculations for T-13
Following the GHG formula and variables for T-13, the following calculations are provided below with representation of the corresponding variables:

GHG Reduction Formula: 𝐴 = 𝐵 𝑥 𝐶
ID Variable Value Unit Source
A Percent reduction in GHG emissions from
project/site commute VMT
0 – 12.0 % calculated
B Percent of employees eligible 100 % User input
C Percent reduction in commute VMT
from implementation of measure
-26 % Shoup 2005
𝐴 = 1 𝑥 −0.12 = −12%
With the recommendation in CAPCOA for 100% for variable B, the resulting maximum percentage for reduction is -12% for mitigating VMT.

VMT Reduction Plan Memo
September 26, 2023

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V. Viability of VMT Reduction Plan Mitigation Strategy
Some of the above Trip Reduction Programs discussed above include variables that are determined by data provided by CAPCOA for the region where the project site is located. Data provided by CAPCOA for the Sacramento Region was used as the input for that variable. In all other cases involving a variable, the applicant has the discretion to select the input (e.g., how many employees are eligible), and can therefore control the relative VMT reduction value of the selected Trip Reduction Programs.

Thus, applying the double-counting rules, and the calculated values of each of the available VMT Reduction Programs for the Sacramento Region, an operator can achieve a 22% reduction target in several different ways.

For instance, an operator may select T-6 (Maximum 26% reduction), T-6 and T-12 (Maximum 45% reduction), or T-6 and T-13 (Maximum 38% reduction), each of which is capable of meeting the mitigation requirements of a minimum 22% VMT reduction. Alternatively, an operator may select T-12 and one or more of T-7 through T-11 (maximum 37.1% reduction), or select T-13 and at least two or more of T-7 through T-11 (maximum 29.1% reduction), either of which are also capable of meeting the mitigation requirements for a minimum 22% VMT reduction. Thus, the operator has full control to ensure the selected Trip Reduction Programs will be able to meet the required -22% reduction target.

VI. Conclusion
Based on the CAPCOA calculations for T-6 through T-13 under the Trip Reduction Programs subsector, the project would be able to mitigate the 128% VMT impact to be less-than significant through the selection of multiple Trip Reduction Programs to achieve a minimum -22% VMT reduction. The owner/operator of each building site(s) shall be required to submit for approval and implement a VMT Reduction Plan that includes a sufficient selection of Trip Reduction Programs T-6 through T-13, while complying with the double-counting rules and providing building site(s) specific calculations, to reduce VMT by at least 22%. Please see attached Appendices for excerpts from the CAPCOA Handbook for additional guidance on the calculations presented in this memo. The full Transportation Chapter of the CAPCOA Handbook can be found through the following link:
https://www.caleemod.com/handbook/chapter_3_1transportation.html.

University of Nebraska - Lincoln
DigitalCommons@University of Nebraska - Lincoln
USGS Staff -- Published Research US Geological Survey
2017
Extending the Habitat Concept to the Airspace
Robert H. Diehl
Northern Rocky Mountain Science Center, [email protected] Anna C. Peterson
University of Minnesota, Saint Paul, [email protected]
Rachel T. Bolus
Southern Utah University, [email protected]
Douglas Johnson
Northern Prairie Wildlife Research Center, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/usgsstaffpub Part of the Geology Commons, Oceanography and Atmospheric Sciences and Meteorology Commons, Other Earth Sciences Commons, and the Other Environmental Sciences Commons Diehl, Robert H.; Peterson, Anna C.; Bolus, Rachel T.; and Johnson, Douglas, "Extending the Habitat Concept to the Airspace" (2017). USGS Staff -- Published Research. 1129. https://digitalcommons.unl.edu/usgsstaffpub/1129
This Article is brought to you for free and open access by the US Geological Survey at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in USGS Staff -- Published Research by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln.

Extending the Habitat Concept
to the Airspace 3
Robert H. Diehl, Anna C. Peterson, Rachel T. Bolus,
and Douglas H. Johnson
Abstract
Habitat is one of the most familiar and fundamental concepts in the fields of ecology, animal behavior, and wildlife conservation and management. Humans interact with habitats through their senses and experiences and education to such a degree that their perceptions of habitat have become second nature. For this reason, it may be difficult at first to accept the airspace as habitat, an area that is invisible, untouchable, highly dynamic, and its occupants difficult to see. Nonetheless, the habitat concept, by definition and in practice, applies readily to the airspace. Some ecological and behavioral processes including habitat selection, foraging, and reproduction are operational in the airspace, while others, particularly those mediated by resource limitation such as territoriality, are likely uncommon if present at all. The behaviors of flying animals increasingly expose them to anthropogenic hazards as development of the airspace accelerates. This exacerbates the need to identify approaches for managing these human–wildlife conflicts in aerial habitats, especially where human safety or at-risk populations are concerned. The habitat concept has proven useful in shaping environmental law and policy to help R.H. Diehl (*)
US Geological Survey, Northern Rocky Mountain Science Center, Bozeman, MT, USA e-mail: [email protected]
A.C. Peterson
Department of Fisheries, Wildlife and Conservation Biology, University of Minnesota, Saint Paul, MN, US
e-mail: [email protected]
R.T. Bolus
Department of Biology, Southern Utah University, Cedar City, UT, USA e-mail: [email protected]
D.H. Johnson
US Geological Survey, Northern Prairie Wildlife Research Center, Jamestown, ND, USA e-mail: [email protected]
# Springer International Publishing AG, part of Springer Nature 2017 P.B. Chilson et al. (eds.), Aeroecology,
https://doi.org/10.1007/978-3-319-68576-2_3
47 mitigate these conflicts. It remains to be seen whether current law can bend to include a more expansive concept of habitat that includes the airspace. 1 What Is Habitat?
Consider an organism moving through a vast and apparently featureless yet dynamic fluid medium. Its behavioral and physical phenotype is designed for life in this medium, and its survival contingent upon its ability to seek out favorable currents in which to move about, find food, sleep, and avoid predators. This might describe the rudimentary natural history of countless pelagic fish species and we would not hesitate to call the open water they occupy a habitat. This might also describe the natural history of numerous bird species and the airspaces they occupy, yet most would claim a bird in flight is not in habitat. The notion of habitat is firmly linked to terrestrial or aquatic places, yet nothing about the ecology of habitats excludes the airspace which shares many ecological parallels with its terrestrial and aquatic counterparts.

Ecologists have struggled to define habitat. Linnæus (1754), his mind on plants, informally referred to “the native places” (where one finds a given species of plant) as “station,” his nascent term for habitat. This concept was developed with principles that apply to sessile plants and which have continued to influence scientific understanding of habitat; however, highly mobile organisms defy our attempts to discretely categorize their habitats by plant communities (e.g., forest, grassland) and/or geological formations (e.g., river, alpine). Linnæus’ general perception of habitat remains widely accepted today, even as a persistent dissatisfaction surrounds a precise definition. Odum’s (1959) definition of habitat as “the place an organism lives, or where one would go to find it” is perhaps the most familiar to ecologists. A few years later, perhaps dissatisfied with this and other definitions, Elton (1966) stated that, “definition of habitat, or rather lack of it, is one of the chief blind spots in zoology,” and efforts to define it continue. Many of the more generalizable definitions of habitat offer some reference to occupancy or resources that promote occupancy (e.g., Hall et al. 1997; Dennis et al. 2003, 2006; Morrison et al. 2006). Of these, Morrison et al.’s is among the more precise and generalizable, calling habitat an “area with a combination of resources and environmental conditions that promotes occupancy by individuals of a given species that allows individuals to survive and reproduce.” More context specific definitions usually involve additional criteria and represent special cases and are therefore less broadly applicable to the life history of organisms as a whole (e.g., by requiring the presence of vegetation). The airspace satisfies criteria set forth in these and other broadly defined conceptions of habitat in that it contains resources that promote occupancy. These include food, mates, opportunities to avoid predators, and a low friction, relatively uncluttered medium enabling efficient travel. The idea that the airspace should be considered habitat (Diehl 2013) is gaining acceptance and is a fundamental tenet of the emerging field of aeroecology (Kunz et al. 2008). 48 R.H. Diehl et al.

It was unclear how long airborne resources could sustain life during flight, particularly of a vertebrate, until Alpine and Common Swifts (Tachymarptis melba and Apus apus) were documented remaining aloft for several months without landing (Liechti et al. 2013; Hedenstr€om et al. 2016). The airspace alone provided all the resources required to sustain the swift’s biology, including food and sleep.

Much as a terrestrial amphibian uses the water only to breed, these swifts appear to need land only to support their nests and eggs. (The word “amphibious” means “leading a double life” in Greek, and had early taxonomists not applied this word exclusively to animals that exist between the land and water, we might also label swifts as “amphibious.”) In addition, recent research shows that the microscopic biological flotsam of the air is composed not only of inert cells and bits of feathers but also of life: pollen, bacteria, fungi, and protists (Depre´s et al. 2012). The airspace is teeming with microbial communities that spend generations aloft before settling back to the surface after metabolizing, undergoing selection, and reproducing (Womack et al. 2010). Such phenomena challenge biologists to accept that the airspace is habitat. The alternative—that such organisms are sustained through large proportions of their lives outside habitat—suggests that the current habitat model be rejected altogether, although it is unclear what might replace it (Dennis et al. 2003). A revised understanding of habitat that includes the airspace offers a new context to consider the habitat concept. Relative to its terrestrial and aquatic counterparts, the airspace is highly dynamic yet presumably lacking in much of the structure and organizational complexity that comes with higher plant and animal abundances, species diversity, and physical substrates typically associated with habitat.

Despite a strong ecological basis that the airspace should be considered habitat, the notion remains counterintuitive and references to the airspace as habitat are vague where they exist at all (e.g., Cadenasso et al. 2003). Through formal education and personal experience, we learn about habitat strictly in terms of land and water. Indeed, among all vertebrates and macroinvertebrates, humans and a relative handful of other species are actually unusual for their inability to fly. Our perceptions shape how we understand and apply the habitat concept in ways that may have consequences for wildlife conservation and management and the education of future generations.

Early hunter-gatherer societies likely cultivated a deep understanding of the natural history of plants and animals, so the awareness of habitat (in the sense that certain resources can be found in certain places at certain times) predates scientific recognition and definition by millions of years. The knowledge of when and where to gain access to resources was critical to survival throughout evolutionary history and therefore linked to resources that were accessible (that is, by land and water, but seldom through the air). As such, perceptions of habitat may be deeply ingrained, possibly even codified in our DNA, and indeed, a genetic basis for habitat preference is well documented among some species (Jaenike and Holt 1991).

Evolution shaped our senses for survival on land and water to a degree that almost certainly influences our perceptions of what constitutes habitat, so considering the airspace as a habitat poses several challenges. The airspace is largely 3 Extending the Habitat Concept to the Airspace 49
invisible as are many of the features that give it structure (e.g., wind, temperature, pressure, geomagnetism). Even those features which are detectable to humans through nonvisual channels (e.g., wind) likely do not carry the same meaning as they do with flying animals. We lack certain sensory receptive organs (e.g., cilia) and the neurological infrastructure that interprets signals from those organs. Moreover, certain characteristics of aerial habitat seem to defy common sense. That a habitat could be invisible or is capable of being present one moment and gone the next is far outside most personal and professional experiences. For example, the convective thermals used by raptors represent aerial habitats that are both invisible and highly ephemeral. Despite these limitations, extensions to our senses offered by access to the airspace though manned and unmanned aircraft and advances in remote sensing technology are beginning to reveal the intricacies of an ecological airspace (Helms et al. 2016; Bridge et al. 2011; Robinson et al. 2009). 2 The Nature of Aerial Habitat
The term “aerial habitat” has been used more in reference to plants than flying animals, specifically in relation to the phyllosphere where the ecology of epiphytes and other arboreal organisms plays out, usually high in the trees (e.g., Lindow and Brandl 2003). What constitutes aerial habitat in the context of aeroecology remains a somewhat open question. In atmospheric terms, aerial habitat includes those parts of the troposphere where aerobiological activity occurs, within the planetary boundary layer and lower parts of the free atmosphere (Davy et al. 2017). Typically, most activity occurs within the first several hundred meters above ground level. In biological terms, aerial habitat occurs when and where an organism’s presence indicates use of an airborne resource (e.g., for food or as a movement corridor).

Many properties of the airspace give rise to variability in the structure of aerial habitat. These include wind speed and direction and their diverse manifestations (e.g., convection, shear, turbulence); various forms of moisture including humidity and cloud; precipitation; temperature; pressure and air density (see Chap. 2); magnetic and gravitational field strengths; odor; light conditions (e.g., polarized light, also Van Doren et al. 2017); and natural and anthropogenic gases, chemicals, and particulate matter. Other properties that may not be considered structural in relation to the airspace itself but are nonetheless influential include aerial predators and prey, topography, and anthropogenic structure (Lambertucci et al. 2015; Shipley et al. 2017). These characteristics influence the likelihood of occupancy for a given species within the occupiable airspace, which has vague upper and lower boundaries.

Animals occupying aerial habitats respond primarily to conditions aloft and are often behaviorally decoupled from land and water surfaces. However, at low altitudes, aerial habitat segues into terrestrial or aquatic habitat and animal behavior aloft is increasingly influenced by surface features. A large literature exists concerning the ecology of habitat interfaces, usually between patches of vegetation (Cadenasso et al. 2003). Where obvious transitions between the primary physical 50 R.H. Diehl et al.
habitat types (land–water, land–air, air–water) have received some attention, the ecology of land–water interfaces dominates. Land–air and air–water interfaces are considered hard boundaries with comparatively abrupt transitions. Research on these boundaries focuses primarily on the physics and chemistry of gas exchange and microbial communities (Belnap et al. 2003) with little attention given to higher trophic levels. In these areas, the airspace may be a functional extension of surface terrestrial or aquatic habitat rather than aerial habitat per se, and time spent aloft by vertebrates and macroscopic invertebrates can be brief and usually occurs irrespective of conditions in the interstitial airspaces (e.g., nectar feeding bats, terrestrial territoriality in birds).

As altitude increases, conditions supporting buoyancy and powered flight diminish and the upper limit for a particular species is determined by the extent to which its behavior, anatomy, and physiology have adapted to decreasing air density, temperature, oxygen, and increasing radiation. Where these upper boundary conditions lie for most species is unknown owing to the difficulty of tracking small organisms. Winds are capable of lifting and dispersing invertebrates, seeds, and numerous microorganisms including pollen, spores, and fungi to altitudes exceeding 50 km (e.g., Drake and Reynolds 2012; Westbrook and Isard 1999; Womack et al. 2010). Among high-flying vertebrates, the bar-headed goose (Anser indicus) may be the most well-studied and most extreme. These geese routinely reach altitudes exceeding 6000 m when transiting the Himalayan Mountains of the Tibetan Plateau (Hawkes et al. 2011, 2013), although these geese and other species have been documented at higher altitudes, including a Ruppell’s Vulture (Gyps rueppellii) which was struck by an aircraft at >11,000 m (Laybourne 1974). At 6000 m, air density and the partial pressure of oxygen is approximately half that at sea level under standard atmospheric conditions. Therefore, oxygen availability to power aerobic flight is considerably reduced just as the demands of flight increase as a result of reduced lift from low air density. Despite these constraints, bar-headed geese are not known to benefit from supportive winds in their trans-Himalayan migrations, instead relying on physiological adaptation to altitude and favoring calm atmospheric conditions (Hawkes et al. 2011). 3 Ecology of the Airspace
Terrestrial and aquatic habitats are home to a long list of ecological and behavioral processes including predation, competition, reproduction, and territoriality. The extent to which many of these processes are operational in the airspace is poorly known and, even if present, may be uncommon, ephemeral, or difficult to detect and observe. Certain behaviors are unambiguously at work including habitat selection, reproductive behavior, and predator–prey interactions. Others, especially those that partition resources such as exploitative competition and territoriality, even when operational, may be too short-lived or ambiguous to be useful.

Persistent resource defense territoriality generally occurs only when resources are defendable, limited, and predictable. In most cases, the energetic cost of 3 Extending the Habitat Concept to the Airspace 51
occupying the airspace may be high relative to that in terrestrial and aquatic habitats as the airspace has no substrate and offers little unassisted buoyant support (at least for most vertebrates). Flying animals must power movement using their own energy reserves or by harvesting energy conveniently available from the wind (Sachs 2016; Pennycuick 1998), either of which limits the defendability of airborne resources.

Also, most properties of the airspace that might serve as airborne resources (e.g., favorable wind, airborne invertebrates as food) may be both unpredictable and effectively unlimited at any given place and time. As a result, resource defense territoriality of airspaces is likely either uncommon or assumes an alternative form than that which has been previously recognized. For example, instead of defending a particular static area bounded in three dimensions, perhaps territoriality manifests as competition in space relative to other individuals (e.g., location in a flock or breeding swarm), which may be more spatially dynamic than the traditional view of a territory. Flying animals, particularly some invertebrates, do use the airspace to defend underlying terrestrial or aquatic habitats and their associated resources. We regard this use of airspace as an extension of surface territoriality as opposed to strict defense of an aerial resource.

Like other difficult-to-study habitats, the airspace offers a relatively unexplored context for examining the generality of ecological theory. If a given ecological process is present because the airspace and organism meet known criteria required for that process to be operational, then the durability of that concept is reinforced.

Alternatively, an ecological process that is present despite the absence of expected criteria may call the generality of theory into question. Similar reasoning applies for ecological processes not present in the airspace. We discuss the occurrence of some of these ecological processes to emphasize the point that the airspace functions as habitat and that the ecology of the airspace in many ways differs little from the ecology of the land and the water.

3.1 Habitat Quality, Use, and Selection
Aerial habitats, like their terrestrial and aquatic counterparts, vary in quality in ways that influence survival and reproductive success (Jones 2001). Organisms react to this variation, although reactions differ among species. Microorganisms may be limited in their ability to “select” habitat, but distinct microbial communities exist in the airspace. Community composition is influenced by adjacent source terrestrial/aquatic habitats (Bowers et al. 2011; Brodie et al. 2007), weather (Harrison et al. 2005), and microhabitat differences in the airspace (Womack et al. 2010). Winds aerosolize microorganisms upward from the land (especially from plants; Vaı¨tilingom et al. 2012) or water and then can horizontally transport the larger microbes and pollen, sometimes for long distances (e.g., from the Sahara to the Alps; Meola et al. 2015), mixing communities. Once they have been passively dispersed, species differ in their ability to survive extreme temperature shifts, radiation, osmotic shocks, and desiccation (Joly et al. 2015), conditions that vary spatially and temporally (Womack et al. 2010). Eventually microorganisms return 52 R.H. Diehl et al.
to earth due to wind drift, sedimentation, or precipitation (Depre´s et al. 2012).

Adaptations to the harsh life of the atmosphere (e.g., pigments to reduce the stress from radiation, cold shock proteins; Joly et al. 2015) have likely contributed to the successful inoculation of life in some of its most extreme aquatic and terrestrial habitats (e.g., polar ice sheets; Gonzalez-Toril et al. 2009).

In contrast to microorganisms’ passive habitat use, flying animals often select habitats because they provide resources in support of some critical behavior such as foraging, reproduction, or migration. For example, migrating birds choose routes and weather conditions (e.g., Fig. 3.1) that allow them to manage the often conflicting goals of minimizing travel time, energy expenditure, and risk (Alerstam and Lindstr€om 1990); these birds often respond to wind support more than temperature and humidity when selecting the routes and altitudes for their movements (Liechti et al. 2000). For instance, to assist their long-distance migrations over the ocean, bar-tailed godwits time departures from Alaska to coincide with weather likely to produce tailwinds (Gill et al. 2009). In contrast, some migratory insects choose their altitudes primarily based on atmospheric turbulence rather than tail wind assistance (Aralimarad et al. 2011). Diurnal soaring birds, such as the golden eagle, restrict their flight to a narrow band of low-altitude airspace as wind speeds increase (Lanzone et al. 2012). These and other forms of aerial habitat selection appear to be non-density dependent, since the resources being selected (e.g., favorable winds) are not thought to be limiting so as to create conditions for competitive exclusion.

A feature of habitat selection that distinguishes it from mere habitat use is that it results from the relationship between the costs and benefits of occupancy. For instance, during nocturnal migration, birds appear to select the lowest altitude where they first encounter supportive wind conditions even if “better” winds occur at higher altitudes (Mateos-Rodrı´guez and Liechti 2012). Presumably birds are unwilling to cross a cost barrier to seek out potentially more advantageous flying conditions suggesting that frequent altitude changes in search of optimal flying conditions may be costly (but see Bowlin et al. 2015).

3.2 Reproduction
The airspace provides many resources supporting reproduction, ranging from the concrete (space for asexual division, gamete dispersal, or copulation; protection from predators) to the abstract (a clear channel for communicating with potential mates). Many plants are pollinated through the action of the wind either directly or indirectly by affecting the flight paths of their pollinators. Bacteria have shorter reproductive cycles than their typical residency times in the air column and may have multiple generations between their ascents and descents (Burrows et al. 2009; Sattler et al. 2001).

Most aerial reproductive behavior in flying animals occurs among invertebrates.

Insect mating swarms can take many forms. Under seasonally appropriate weather conditions, Diptera form highly localized mating swarms and may maintain 3 Extending the Habitat Concept to the Airspace 53
Fig. 3.1 (a) Weather radar reflectivity at 3.51 antenna elevation from Brownsville, TX (KBRO) showing layered bird migration on 12 May 2006, 2330 CST.

A white dot shows the location of the radar. (b) The vertical profile of reflectivity computed from the radar reflectivity volume scan on this day, and the (c) associated wind profile showing the direction from which the wind was blowing that day at 1900 CST. The dashed circles in (a) represent 16 and 32 km rangerings and correspond to the ~1000 and ~2000 m height AGL dashed lines, respectively, in (b) and (c) 54 R.H. Diehl et al.
consistent locations with respect to conspicuous “swarm markers” in the landscape (e.g., a geographic feature or patch of sunlight; Sullivan 1981). Alternatively, mating swarms may occupy enormous areas (Dublon and Sumpter 2014). The mayfly swarming event depicted in Fig. 3.2 occupies more than 3000 km2 of Lake Erie’s surface, at least 12% of its total area. Emergence generally occurs when both water temperatures exceed 20 C (Corkum et al. 2006) and winds are moving toward the shore, as molting occurs on land after emergence; therefore, aerial habitat selection affects reproductive timing. Aerial reproductive swarming of this magnitude also serves as predator defense, as the massive pulse of food for local predators overwhelms the predator community to the point of satiation (Sweeney and Vannote 1982; but see Allan and Flecker 1989). Aerial copulation is common among invertebrates (e.g., Scott 1972; Allan and Flecker 1989), but appears to be rare among vertebrates. However, there is some evidence that red bats Fig. 3.2 Emergence of Hexagenia mayflies from western Lake Erie on 18 June 2015, 2204 CST as captured by Cleveland, Ohio weather radar, KCLE (white dot). Radar reflectivities (dBZ) show varying mayfly densities aloft. The line segment in the upper image (a) west of the radar identifies the south-to-north cross section through the radar’s volume scan shown below (b) 3 Extending the Habitat Concept to the Airspace 55
(Lasiurus borealis) and hoary bats (Lasiurus cinereus) copulate in flight (Cryan and Brown 2007).

The airspace is an important area for mating displays across taxa. Aerial lekking has been described for some insects (e.g., Lepidoptera, Andersson et al. 1998).

Eusocial insects, particularly the Hymenoptera and Blattodea (e.g., termites), often make nuptial flights, although many of these occur close to the ground, where the role of the airspace may be limited (e.g., Dial and Vaughan 1987). Some bats may respond to turbulence when choosing mating display locations; this hypothesis has been suggested as an explanation for why bats congregate in the lee of wind turbines, a behavior which unfortunately often results in mortality (Cryan et al. 2014). Many birds have song flights and elaborate aerial displays, including the roding display of the Eurasian woodcock (Scolopax rusticola; Hoodless et al. 2008), the dive and shuttle of Anna’s hummingbird (Calypte anna; Stiles 1982), and the sky dancing of the Montagu’s harrier (Circus pygargus; Arroyo et al. 2013).

In addition to visual displays, many acoustic and olfactory breeding signals are transmitted through the air, including an assortment of vocalizations, stridulations, airborne pheromones, and pollinator attractors. Many of these signals evolved characteristics that allow them to travel efficiently through the air to receivers, taking forms that propagate with minimal degradation (Morton 1975). The signals themselves compete for airspace, or at least clear transmission through it, by varying in ways that minimize overlap within a community (Nelson and Marler 1990). This variation can either be an adaptive characteristic of a species- or population-specific signal (e.g., a distinct floral scent; Wright and Schiestl 2009) or the result of an individual modulating its signal in real time in response to current acoustic or olfactory “clutter” (e.g., modulating a bird song frequency to avoid overlap with noise; Goodwin and Podos 2013).

3.3 Foraging, Competition, and Resource Partitioning
The airspace supports considerable foraging habitat for many aerial specialists and obligate insectivores (e.g., swallows, flycatchers, insectivorous bats). Other flying animals depend upon predictable seasonal resource pulses (Yang et al. 2008).

Usually these occur as the invertebrate mating swarms described above, but some aerial predators have adapted to exploit seasonal songbird migrations as a food source. The giant noctule bat (Nyctalus lasiopterus) will opportunistically switch diets to prey almost exclusively upon migrating songbirds (Popa-Lisseanu et al. 2007; Fukui et al. 2013). Eleonora’s falcon (Falco eleonorae) also takes migrating songbirds in flight and appears to synchronize its reproduction with the seasonal availability of this food source (Wink and Ristow 2000). Similarly, peregrine falcons (Falco peregrinus) and red-tailed hawks (Buteo jamaicensis) hunt outside the large breeding colonies of insectivorous Brazilian free-tailed bats (Tadarida brasiliensis; Lee and Kuo 2001), which in turn prey on migrating noctuid moths.

This sets up an aerial tritrophic interaction (raptors > bats > noctuid moths) that occurs each summer and is mediated by abiotic conditions in the airspace that 56 R.H. Diehl et al.
determine the favorability of conditions for moth migration (McCracken et al. 2008).

Intra- and interspecific competition over aerial food resources also occurs in the airspace, although the difficulty in defending airborne resources together with limited niche overlap among competitors reduces the likelihood that such competition will arise (Mills 1986). Bats and common nighthawks (Chordeiles minor) have been observed in competitive interaction over insects at a human light source (Shields and Bildstein 1979). Altitudinal resource partitioning is hypothesized to explain differences in niche breadth among some avian aerial insectivores, wherein physical adaptations have allowed certain swift species to forage at higher altitudes and take advantage of larger and higher flying insects, thus reducing competition with swifts at lower altitudes (Collins 2015). Several species of desert bats differed in the locations and timing of foraging bouts over water sources in the Central Negev Highlands of Israel, suggestive of aerial resource partitioning due to competition for a shared insect resource (Razgour et al. 2011). 4 Anthropogenic Impacts
Even as human encroachment into the airspace advances, it is difficult to know whether certain taxa experience non-compensatory levels of mortality (Drewitt and Langston 2006; Kunz et al. 2007) which complicates how development of the airspace can be managed to reduce impacts to flying animal populations. In this context, recognizing the airspace as habitat may have meaningful consequences for species conservation and management. The habitat concept is necessarily central to international species-based environmental law (e.g., US Endangered Species Act and National Environmental Policy Act, EU’s Habitats Directive and Birds Directive) and influences how biologists that work for regulatory agencies interpret the law in practice. That many parts of the airspace fall within the habitat concept could change the scope of application of these laws to include vast new areas. However, regulatory references to the airspace as habitat are scant; we could find only one and it argued against recognizing the airspace as habitat. In the context of a review of New Zealand’s Resource Management Act which recognizes protection of significant habitats, Wallace (2007) specifically argues against characterizing flight corridors or migration routes as habitat because those areas are “disconnected from breeding and feeding spaces.” Aside from being imprecise (many organisms do breed and feed in the airspace, even if the waterbirds considered by this Act do not), the point is also irrelevant since breeding and foraging are not required characteristics of habitat and are not the only habitat-related behaviors critical to survival (e.g., hibernating, roosting; Cryan and Veilleux 2007, Mehlman et al. 2005). Even if waterbirds were the only taxon of concern for a regulatory agency, they repeatedly travel similar routes between feeding and roosting locations (Everaert and Stienen 2007; Cox and Afton 1996), so any anthropogenic disruption in their path could have negative consequences on their populations by increasing mortality and decreasing reproductive success. Recognizing the airspace as habitat 3 Extending the Habitat Concept to the Airspace 57
is critical for species conservation and management that consider entire life histories (Davy et al. 2017).

4.1 Threats to Aerial Organisms
The actions of society through development, commerce, transportation, policy, and resource extraction increasingly result in conflicts with flying animals that have impacts ranging from the safety of airline travel (Dolbeer and Wright 2008) to the price of corn (Boyles et al. 2011). The increasing construction of tall structures may result in long-term disruptions of aerial habitats, including wind turbines (Arnett et al. 2010); power lines (Martin 2011; Bevanger 1998); buildings, especially those using glass construction (Loss et al. 2014; Klem 1990); and some communications towers (Gehring et al. 2011; Gehring et al. 2009). One of the newest anthropogenic entrants to the airspace, unmanned aircraft systems (UAS), pose possible threats in that they may interfere with natural animal behavior and in other ways disrupt aerial ecosystems (e.g., Lambertucci et al. 2015). Current US federal guidelines allow UAS operations in all classes of airspace except those in the vicinity of airports (Class B; Federal Aviation Administration 2015a), but because proposed guidelines require operators to keep UAS within visual line-of-sight (Federal Aviation Administration 2015b), UAS use generally occurs relatively close to the ground within the region of most flying animal activity.

Anthropogenic development of the airspace creates novel challenges for flying animals, many of which are not adapted to flying in cluttered environments. Put another way, “perceptually [birds] have no prior for human artifacts such a buildings, power wires or wind turbines” (Martin 2011). In addition, not only may organisms lack the sensory capabilities to avoid development, but their senses may trick them into responding inappropriately to it. Ecological traps occur when rapid changes in the environment produce misleading cues about the quality of habitats. Based on these cues, organisms may select lower quality habitat which leads to lower survival or reproductive success, even though higher quality habitat may be available. Numerous examples of ecological traps have been documented for terrestrial habitats, and anthropogenic factors are usually responsible (Robertson and Hutto 2006; Schlaepfer et al. 2002). The airspace is no exception.

Migrating birds drawn into circling illuminated communications towers, particularly those with guy wires, in low cloud conditions die in large numbers (Gehring et al. 2009; Larkin and Frase 1988). Under these conditions, airspace in the vicinity of lighted towers might be considered low-quality aerial habitat. Nonetheless, birds in these circumstances remain in flight, presumably because the hazy glow of a lighted tower in cloud is in some way attractive. Similarly, bats that die in the vicinity of wind turbines may select this aerial habitat, perhaps as a mating location or because turbines concentrate insects as food (Cryan et al. 2014).

Anthropogenic structures and machines in the airspace are not the only threat to aerial organisms. Chemicals and particulate matter as air pollutants also degrade aerial habitats, and the impacts of air pollution on animals in flight are poorly understood. Is the health of flying animals disproportionately affected owing to 58 R.H. Diehl et al.
their relatively high metabolic rates during flight? Does air pollution interfere with olfactory or visual cues necessary for foraging, reproduction, and orientation? Might pollution that impacts aerial invertebrates have a trophic effect on their aerial predators? Does extreme air pollution impede visibility enough to increase risk of collisions with structure? Does pollution interfere with the composition and metabolic processes of aerial microbial communities in ways that affect climate and human health?
Anthropogenic structures that intrude upon aerial habitats can be designed, refitted, or adapted to limit their impacts on flying animals. Communications towers can be designed with lighting and structural support that reduces collision risk (Gehring et al. 2009). Curtailment of wind turbines has been shown to reduce bat mortality (Arnett et al. 2010), and current research is exploring ultraviolet (UV) illumination of turbines as a way of dissuading bats from approaching altogether (Gorresen et al. 2015). Combination camera/acoustic detection and deterrence systems are being explored as a means of reducing eagle mortality at wind facilities (Sinclair and DeGeorge 2016). A variety of markers are now available which increase the visibility of powerlines to birds in flight (e.g., Sporer et al. 2013). UV reflecting patterns on glass, which are visible to birds but not humans, may be effective at deterring birds from colliding with glass structure (Klem 2009).

Where technological deterrents are impractical or otherwise ineffective, the airspaces themselves may require protection. Airspace reserves may be needed to support the conservation of species as human development of aerial habitats continues and populations face compounding pressures across all phases of their life cycle (e.g., terrestrial habitat loss, mismatched phenology through climate change, predation and competition from nonnative species). Such reserves might focus on regulating development of the airspace near traditional movement corridors or in other areas where high densities of aerial organisms commonly occur or where species of concern are prone to fly (Diehl 2013; Lambertucci et al. 2015). Aerial reserves may be appropriate in areas where human–wildlife conflicts become a human safety concern or development presents a population-level risk to flying organisms or the ecological services they provide.

The preservation of aerial habitats may be quite different than traditional approaches for terrestrial and aquatic habitats. Most terrestrial and aquatic habitat preservation focuses on particular areas of concern and is intended to be continuous and long term, as disturbance can have lasting effects. In contrast, many human– wildlife conflicts are temporally dependent. Where animal use of aerial habitat is predictable, preservation may involve the timing of human activities rather than permanent restrictions on a particular area. For instance, proper lighting and curtailment of wind turbines when flying animals are most active can reduce or eliminate systematic impacts (Arnett et al. 2010; Duerr et al. 2012). Turbine curtailment could conceivably occur over even short timescales such as when fog or low cloud interferes with animals’ ability to avoid structures (Kirsch et al. 2015).

Many North American cities participate in seasonal lights-out programs, turning off the lights of large city buildings during peak bird migration times. These examples 3 Extending the Habitat Concept to the Airspace 59
illustrate how anthropogenic hazards to flying animals can be reduced by timing the use of airspaces to complement animal phenology.

Brazilian free-tailed bats offer an interesting conservation case study. Brazilian free-tailed bats are migratory and roost during summer in caves across the southern tier of the continental USA, with exceptionally large concentrations in central Texas (Wilkins 1989). Bracken, Frio, and other caves in this region host summer maternity colonies containing millions of these bats; the colony in Bracken Cave is one of the largest single bat colonies in the world (McCracken 2003). In the evenings, they depart the caves en masse to forage on noctuid moths and other insects near the planetary boundary layer (Westbrook 2008; Fig. 3.3).

Conservation organizations acquired land to protect terrestrial habitat in the immediate vicinity of the cave entrance. Protecting these areas from human development indirectly offers overlying airspaces some associated protection by excluding potentially hazardous anthropogenic structures (e.g., wind turbines, communications towers) from the immediate area. Protection of Bracken Cave and its airspace preserves the phenomenon of mass exodus (sensu Brower and Malcolm 1991), the biological integrity of its populations (e.g., Allee effects, Langwig et al. 2015), the ecological services these bats provide to agriculture (Boyles et al. 2011; Davidai et al. 2015), and the educational opportunities afforded by these conspicuous movements (Pennisi et al. 2004). Even though Bracken and other caves in the region are occupied only half of the year (March through October), protecting the integrity of the cave itself from any form of development or even routine visitation is a year-round necessity as the cave represents a nonrenewable resource for bats. The immediate overlying airspace is also critical habitat as millions of bats transit this space when moving to and from foraging habitat. In contrast to the protection of the cave, aerial habitat in the vicinity of the cave could be considered renewable and its preservation seasonal.

The reserve concept is often oriented toward nonhuman species protection, but understanding and perhaps regulating airspace use with respect to flying animals has financial and human safety implications as well. From 1990 to 2007, bird strikes by civilian aircraft accounted for the overwhelming majority of monetary losses associated with wildlife strikes (~$125 to ~$625 million annually in the USA) and resulted in 10 fatalities and 164 injuries (Dolbeer and Wright 2008). After US Airways Flight 1549 struck a flock of Canada Geese (Branta canadensis) and crash landed into the Hudson River, there were calls for improved monitoring of bird movements (Marra et al. 2009).

Bird-avoidance models exist that combine both historic and current data to identify times and places of increased risk of bird strikes for low-flying aircraft (Shamoun-Baranes et al. 2008). These warning systems forecast hazards using near real-time feedback from biological data collected from weather radar. However, classification algorithms designed to identify and extract biological data from weather radar data streams are rudimentary at best. Currently, no published algorithms exist that can differentiate among types of biological echoes (i.e., taxa) on weather radars, although some effort has been made to distinguish biological from nonbiological radar echoes (Park et al. 2009; Bachmann and Zrnic´ 2007).
60 R.H. Diehl et al.

Fig. 3.3 Series of weather
radar sweeps showing the
evening exodus of Brazilian
free-tailed bats from Frio
Cave (yellow dot) near
Concan, Texas, during the
evening of 22 July 2014. The
white dot shows the location
of the weather radar (KDFX)
at Laughlin AFB, Texas.

Colors show differential
phase, a radar polarimetry
measure used here because it
best distinguishes emerging
bats (browns, yellows, and
dark greens) from other radar
bioscatterers (light green).

The first four sweeps are
separated by 10 min; the fifth
sweep occurred 30 min after
the fourth and shows the
movement more developed
and bats emerging from other
roosts in the vicinity
3 Extending the Habitat Concept to the Airspace 61
Identifying radar echoes to taxon is critical to the operational usefulness of any near real-time warning system, since large birds pose the greatest hazard to manned aircraft (Dolbeer and Wright 2008). Reliable information on the passage of large birds would enable responders to manage aircraft altitudes and approach and departure times and directions as needed. Figure 3.4 shows a typical autumn Fig. 3.4 Weather radars capture a moment during the onset of waterfowl migration toward the SSE across southeastern Wisconsin and northeastern Illinois on 22 Nov 2010, at ~17:45 CST. A 10 km diameter airspace centered on O’Hare International Airport is represented by a yellow circle. The inset shows changes in the estimated number of birds within this circle as the migration begins and progresses. (The abundance calculation assumes mallard-sized birds for simplicity and because good estimates of radar cross section are available for Mallards (Anas platyrhynchos) to convert radar reflectivity to bird numbers (O’Neal et al. 2010; Chilson et al. 2012b); the likely presence of larger birds such as geese and perhaps some cranes reduces these estimates of bird abundances.). The arrow indicates when in the time series this radar capture occurred 62 R.H. Diehl et al.
waterfowl migration toward the SSE with ducks, Canada Geese, and some Sandhill Cranes (Grus canadensis) departing habitats throughout southeastern Wisconsin and northeastern Illinois. Waves of waterfowl passed through the airspace of O’Hare International Airport, near Chicago, Illinois (Fig. 3.4, time series). In this image, the northern-most band of waterfowl radar echoes running west of the “Lake Michigan” label passed through O’Hare airspace at ~19:50 and was responsible for the large pulse of waterfowl seen in the time series. These migratory pushes out of southeastern Wisconsin occur routinely each autumn, so during this time O’Hare becomes both heavily used commercial airspace and seasonally predictable waterfowl aerial habitat. 5 Conclusions
Definitions matter. How habitat is defined influences law, policy, and the actions of resource managers in interpreting policy. Frequent efforts to redefine habitat in ways that capture perceived shortcomings testify to the continuing importance of the habitat concept. The airspace easily satisfies widely recognized definitions of habitat and shares many ecological properties of other more familiar habitat types.

Considering the airspace as habitat also encourages new perspectives on the habitat concept. For example, airspace lacks many of the familiar visible cues we associate with habitat such as vegetation, substrate, or topographic relief. The energetic costs of occupying aerial habitats are often high, and critical aerial resources can be simultaneously abundant, ephemeral, and unpredictable with respect to any one location. Identifying properties shared across all major habitat types—terrestrial, aquatic, and aerial—clarifies our understanding of habitat by focusing our attention on its most fundamental and essential elements.

Considering the airspace as habitat also reminds us that time as much as place is a critical component of habitat, since many of the airspace’s resources for flying animals depend upon the weather and are therefore highly dynamic. Yet, many widely recognized definitions of habitat explicitly refer only to place and tend to reinforce a rather static notion of habitat (but see Dingle 2014; Southwood 1977).

This conforms with human perception of habitats as generally stable through time, at least in the manner we are accustomed to instinctively experiencing them, even if academically, we might recognize that the suitability of nearly any habitat for a given species varies through time, often seasonally if not through ecological succession or some other biotic or abiotic process. In short, that habitat is “where one would go to find it” (Odum 1959) is no more important than when one would go to find it.

The habitat concept has proven to be influential in shaping and informing environmental law and natural resource management in many countries. It is unknown whether aerial habitat represents an expansion of the habitat concept that is applicable under existing law, for example, if the need should arise to create airspace reserves or otherwise regulate the airspace to ensure human safety or protect animal populations. Accelerating human occupancy and development of 3 Extending the Habitat Concept to the Airspace 63
aerial habitats has created a greater need for regulation of the airspace, and clarification of the habitat concept is critical for developing or interpreting laws and regulatory practices that protect species when and where they are present.

We have much to learn about the ecology of the airspace. The dynamism of aerial habitat leads to dynamism of aeroecological processes generally, making them challenging to study, even with the aid of contemporary technology (Chilson et al. 2012a; Bridge et al. 2011). Recognizing that the airspace is habitat allows the known ecology of terrestrial and aquatic habitats to serve as models for predicting the conditions required for a wide range of ecological and behavioral processes to be operational in the airspace.

Acknowledgements We thank S. Soileau, H. Hoffmann, and the editors for helpful input on this chapter. The USGS Northern Rocky Mountain Science Center Ecolunch group provided valuable feedback as the concept of aerial habitat was developed. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

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Sacramento City CouncilNovember 18, 2025

Sacramento City Council
November 18, 2025