20080206final_order_no_30498.pdf

Office of the Secretary
Service Date
February 6, 2008
BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION
IN THE MATTER OF THE APPLICATION
OF A VISTA CORPORATION DBA A VISTA
UTILITIES FOR AN ORDER
AUTHORIZING A CHANGE IN
DEPRECIATION RATES FOR GAS AND
ELECTRIC PLANT
CASE NOS. AVU-07-
A VU-07-
ORDER NO. 30498
On November 1 , 2007, Avista Corporation dba Avista Utilities filed an Application
requesting that the Commission approve changes to the Company s depreciation rates for electric
and natural gas property. Avista serves customers in Washington, Idaho and a small portion of
Oregon. A vista requested that the Commission synchronize depreciation rates so that its Idaho
rates would become effective with new Washington depreciation rates recently approved by the
Washington Utilities and Transportation Commission (WUTC). The Company requested that its
proposed changes to its depreciation rates become effective January 1 2008.
On November 26, 2007, the Commission issued a Notice of Application and
established a deadline for intervention. No person moved to intervene in the case. On February
, 2008 , A vista and Commission Staff filed a Stipulation agreeing upon changes to A vista
depreciation rates. The parties urge the Commission to approve the new depreciation rates
retroactively as of January 1 2008. Based upon our review ofthe Application and the settlement
Stipulation, we approve the parties' stipulated depreciation rates.
BACKGROUND
In April 2007, A vista filed a general rate case application with the WUTC to increase
its rates for electric and natural gas service in Washington. As part of its rate case, the Company
proposed to change its depreciation rates based upon a new depreciation study completed
Gannett Fleming, Inc. The depreciation study was based upon depreciable electric, gas and
common plant in-service as of December 31 , 2004. Application at 2. In October 2007, A vista
the WUTC staff, and other intervenors in the Washington case agreed to accept the depreciation
rates proposed in the depreciation study with four exceptions proposed by the WUTC staff. The
WUTC staff proposed reductions in negative net salvage values in four electric accounts. The
four accounts include: Account 311 (Structures & Improvements); Account 312 (Boiler Plant
Equipment); Account 356 (Overhead Conductor and Devices); and Account 369 (Services).
ORDER NO. 30498
approved, the recommended changes in these four accounts would result in lower depreciation
accrual rates than originally proposed by the Company. On October 29, 2007, the parties in the
Washington case agreed to settle all issues in the general rate case and recommended a proposed
effective date of January 1 , 2008. On December 19, 2007, the WUTC approved the settlement
stipulation including Staffs adjustments to the four depreciation accounts.
THE IDAHO APPLICATION
Avista s depreciation Application in Idaho updated the Company s depreciation
study based upon all plant in-service as of December 31 , 2006. Based upon the depreciation
settlement in Washington, Avista asserted the annual depreciation expenses for electric property
in Idaho should be increased by approximately $128 000 and decreased by approximately
$132 000 for its natural gas property. Application at 4. The Company maintained that approval
of the new depreciation rates would be for accounting purposes only and the Company did not
seek a change in customer service rates at this time. If approved, the new depreciation rates
would become effective January 1 , 2008 and the net change in depreciation rates "would be
reflected in Avista s next general rate case.Id. at 4-5; Order No. 30467 at 2.
THE SETTLEMENT STIPULA TI 0 N
Given the lack of any intervenors, A vista and Staff met to discuss the proposed
depreciation rates. Following these discussions, Avista and Staff agreed that to maintain uniform
utility accounts, the depreciation rates for "system-allocated plant (i., production, transmission
and certain general plant) must be uniform and consistent among the Company s Idaho and
Washington regulatory jurisdictions." Stipulation at ~ 8. The Staff and the Company also agreed
to extend the remaining service life for Idaho Account 367 (Underground Conductor and
Devices). See Atch. B , p. 5 of 7. This Idaho jurisdictional change in the depreciation rate results
in an annual reduction in electric depreciation expense of approximately $668 000. The parties
agreed to the proposed depreciation expense for gas plant contained in A vista s Idaho
Application. If approved, the change in the lives for gas plant would result in an annual decrease
in gas depreciation expense for Idaho of approximately $132 000. Finally, the parties agreed that
the changes in depreciation rates contained in the Stipulation should become effective as of
January 1 2008.
I On January 17, 2008 , A vista notified the Idaho Commission that it intends to file a general rate case on or about
April 1 , 2008.
ORDER NO. 30498
The parties asserted that the proposed depreciation rates contained in the Stipulation
are in the public interest and that the proposed depreciation rates are fair, just and reasonable.
Stipulation at ~ 17. The parties urged the Commission to accept the Stipulation. The Staff and
the Company were the only parties in the case. They insisted the changes encompassed in the
Stipulation decrease annual depreciation expenses and are a benefit to Idaho ratepayers.
Accordingly, the parties asked that the Commission approve the Stipulation and adopt the terms
and conditions without further proceedings.
COMMISSION FINDINGS
After reviewing the depreciation Application and the settlement Stipulation, we find
it is reasonable to approve the Stipulation. As indicated above, based on plant in-service as of
December 31 , 2006, the Stipulation results in a decrease of approximately $668 000 in A vista
annual electric depreciation expense and a decrease of approximately $132 000 in its annual gas
depreciation expense for its Idaho jurisdictional operations. See Atch. A. The parties proposed
and we authorize uniform utility depreciation rates for system-allocated plant between the
Company s Idaho and Washington regulatory jurisdictions. Pursuant to our authority in Idaho
Code ~ 61-525, we find the depreciation rates contained in the Stipulation for both electric and
gas plant are fair, just and reasonable.
Consistent with our procedural Rule 274, we find it is appropriate for the
Commission to summarily accept the settlement of these depreciation rates.IDAPA
31.01.01.274. Based upon the lack of intervenors and our review of this matter, we find that an
evidentiary hearing in this matter is not necessary. In conclusion, the Commission finds the
depreciation rates embodied in the Stipulation are fair, just and reasonable, and in the public
interest. We further find the new depreciation rates contained in the Stipulation shall become
effective as of January 1 2008.
ORDER
IT IS HEREBY ORDERED that the Stipulation dated February 1 , 2008, between
A vista Corporation dba A vista Utilities and Commission Staff is approved. A vista
depreciation rates for Idaho electric and gas properties set out in the parties' Stipulation are
approved for the Idaho jurisdiction. The approved depreciation rates are contained in the
Attachments to this Order.
ORDER NO. 30498
IT IS FURTHER ORDERED that the stipulated depreciation rates shall be effective
as of January 1 , 2008.
THIS IS A FINAL ORDER. Any person interested in this Order (or in issues finally
decided by this Order) or in interlocutory Orders previously issued in this Case Nos. A VU-07-
11 and A VU-07-03 may petition for reconsideration within twenty-one (21) days of the
service date of this Order with regard to any matter decided in this Order or in interlocutory
Orders previously issued in these cases. Within seven (7) days after any person has petitioned
for reconsideration, any other person may cross-petition for reconsideration. See Idaho Code
61-626.
DONE by Order of the Idaho Public Utilities Commission at Boise, Idaho this tD 1-1'
day of February 2008.
~~~
MACK A:'RE,DFO IDENT
MARSHA H. SMITH, COMMISSIONER
ATTEST:
D. JewellCo isslOn Secretary
bls/O:A VU-07-A VU-07-dh2
ORDER NO. 30498
ATTACHMENT A
AVISTA UTILITIES
Depreciation Expense - Electric
For the Year Ended December 31 2006
2006 Deprec. at 2006 Deprec. at
Existing Rate Proposed Rate Change Allocation Allocation
Production Plant:
Steam Production Plant 388 515 174 951 213 564)(798 889)(414 675)
Hydraulic Production Plant 208 522 629 652 421 130 277 230 143,900
Other Production Plant 10,625 177 796,613 828,564)203,743)(624 820)
Total Production Plant 28,222 214 601 216 620,998)725 402)(895 595)
PIT Ratio 65.830%34.170%
Transmission Plant 049 748 614 061 (1,435,687)(945 113)(490 574)
PIT Ratio 65.830%34.170%
Distribution Plant 17,457,435 689 392 231 958 120,428 111 530
Depreciable Plant-ADP-12A
General Plant-See Allocation WS 693,473 530 438 163 035)(770 045)(392 990)
Depreciable Plant-ADP-12A 66.210%33.790%
TOTAL ELECTRIC PLANT 61,422 870 60,435 107 (987,762)(320 132)(667 629)
DEFERRED TAX IMPACT ~ 35%(112 046)(233 670)
ID Accumulated DepreciationlDeferred Tax Impact:
Accumulated
Depeciation Balance
Dec-05
Jan-06 (55 636)
Feb-06 . (111 272)
Mar-06 (166 907)
Apr-06 (222 543)
May-06 (278 179)
Jun-06 (333 815)
Jul-06 (389 450)
Aug-06 (445 086)
Sep-06 (500,722)
Oct-06 (556 358)
Nov-06 (611 993)
Dec-06 (667 629)
Average of Monthly Average (333 815)
Deferred FIT
Balance
(19,473)
(38 945)
(58,417)
(77 890)
(97 363)
(116 835)
(136 308)
(155 780)
(175 253)
(194 725)
(214 198)
(233 670)
(116 835)
ATTACHMENT A
Page 1 of 2
Case Nos. A VU-07-11/A VU-07-
ORDER NO. 30498
ATTACHMENT A
AVIST.A, UTILITIES
Depreciation Expense - Gas
For the Year Ended December 31, 2006
862,876 561 878 (300,998)(214 542)(86,456)
71.277%28.723%
177,423 152,821 (24,602)(18,046)(6,557)
73.3:'0%26.650%
99,447 85.072 (14,375)(10 544)(3,831)
i'3.3S0%26.650%
968.561 924 547 (44 014)(30,394)(13.620)
69.055%~~O,845O
.;'
534.295 068.430 (465,865)(333 582)(132,284)
(116,754)(46.299)
Underground Storage Plant
System Contract Demand Ratio
2006 Depree. at
Existin Rate
425,988
Distribution Plant
Actual Therrns PurChased
General Plant - Direct
System Contract Demand Ratio
Transportation PJant - Direct
System Contract Demand Ratio
General Plant-See Allocation WS
Depreciable Plant-ADP-12A
2006 Depree. at
Pro osed Rate
344 112
Chan
(81.876)
WA
Allocalion Allocation
(60,056) (21 820)
73.350% 26.650%
TOTAL GAS PLANT
DEFERRED TAX IMPACT ~ 35%
10 Accumulated Depreciation/Deferred Tax Impact:
Accumulate,!
eciation BalanceDee-OS
Jan-06 (11.024)
Fob-Oe (22 047)
Mar-O6 (33,071)
Apr-O6 (44,095)
May-06 (55.118)JurI-OB (66,142)
Jut-OB (77,166)
Aug-06 (88,189)
Sep-O6 (99,213)
Oct-06 (110 237)Nov-oe (121 260)Dec-Q6 (132.284Average of Monthly Average (66,142)
Deferred FIT
BalanG€'
(3.858)
(7,716)
(11 575)
(15.433)
(12.291)
(23 150)
(27 008)
(:,0 866)
(34 725)
(38,583)
(42.441)
(46 299)
(23,150)
ATTACHMENT A
Page 2 of 2
Case Nos. A VU-07-11/A VU-07-
ORDER NO. 30498
ATTACHMENT B
AVISTA UTILITIES
Depreciation Expense
For the Year Ended December 31 , 2006
(1)(21 (31 (4)(5)(6)(7)
Existing Proposed
Account 2006 Avg.Existing Annual Study Annual Increase or
Number Description Balance Rate Deprec.Rate Deprec.(Decrease)
STEAM PRODUCTION PLANT
KETTLE FALLS STATION
310.3 Removing Property of Others 138 175 159 026 133)
310.4 Easements & Permits 000 301 219 (82)
311.0 Structures & Improvements 20,949 975 647,446 490,229 (157 217)
311.1 Structures & Improvements-Landfill 572 905 110 403 128 982 18,579
312.0 Boiler Plant Equipment 057 733 307 130 325 911 781
314.0 Turbogenerator Units 085 802 426 998 416 129 (10 869)
315.0 Accessory Electric Equipment 10,261 817 303 750 281 174 (22 576)
316.0 Misc. Power Plant Equipment 304 425 936 759 177)
Total 380 832 869,123 707,428 (161 695)
COLSTRIP UNIT 3
311.0 Structures & Improvements 449 209 478 188 150 242 (327 946)
312.0 Boiler Plant Equipment 529 150 325 393 012,287 (313 106)
314.0 Turbogenerator Units 653 753 547 079 598 462 51,383
315.0 Accessory Electric Equipment 037 535 249 667 2.49 225 035 (24,632)
316.0 Misc. Power Plant Equipment 733 616 238 421 197 380 (41 041)
Total 160 403 263 838 748 183,406 (655 342)
COLSTRIP UNIT 4
311.0 Structures & Improvements 568,467 1,462 270 164 859 (297 411)
312.0 Boiler Plant Equipment 670,162 1,451 536 320,766 (130 770)
314.0 Turbogenerator Units 15,211,778 472 782 532,412 59,630
315.0 Accessory Electric Equipment 372 170 178,646 165 039 (13 607)
316.0 Misc. Power Plant Equipment 107 359 115,410 2.46 101 041 (14 369)
Total 121 929 936 680 644 284 117 (396,527)
Total Steam Production Plant 372 714 031 388 515 174 951 213 564)
ATTACHMENT B
Page 1 of 7
Case Nos. A VU-07-11/A VU-07-
ORDER NO. 30498
ATTACHMENT B
AVISTA UTILITIES
Depreciation Expense
For the Year Ended December 31 , 2006
(1)(2)(31 (4)(5)(6)(7)
Existing Proposed
Account 2006 Avg.Existing Annual Study Annual Increase or
Number Description Balance Rate Deprec.Rate Deprec.(Decrease)
HYDRAULIC PRODUCTION PLANT
CABINET GORGE
330.3 Removing Property of Others 783 237 901 153 979 112 078
330.31 Removing Property of Others-Conservation 240 922 5,469 467
330.4 Land Easements 365 924 260 063 803
330.41 Land Easements-Conservation 332 796 571 6,756 185
331.0 Structures & Improvements 296 356 346 820 150 601 (196.219)
331.1 Structures & Improvements-Fish & Wildlife 610 397 159 (238)
331.2 Structures & Improvements-Recreation 592,490 349 717 (11 632)
331.26 Structures & Improvements-Rec Info 242 908 2.47 599 (309)
332.0 Reservoirs, Dams & Waterways 499 008 478.514 313,232 (165 282)
332.1 Reservoirs, Dams & Waterways-Fish & Wildlife 881 198 299 72,318 019
332.15 Reservoirs, Dams & Waterways-Fish & Wildlife 986 319 1 ,434 587 153
332.2 Reservoirs, Dams & Waterways-Recreation 107 153 951 047 (904)
333.0 Waterwheels, Turbines & Generators 007 087 397 225 828,984 431 759
334.0 Accessory Electric Equipment 227,443 272 644 1.43 752 (197 892)
335.0 Misc. Power Plant Equipment 342,515 712 (11 712)
335.1 Misc. Power Plant Equipment-Fish & Wildlife 938 746 643 897
335.2 Misc. Power Plant Equipment-Recreation 647 303 587 284
336.0 Roads, Railroads & Bridges 098,564 179 22,521 (35,658)
Total 79,870,449 642 215 676,013 798
LITTLE FALLS
330.1 Settlement 200 000 88,216 000 216)
330.3 Removing Property of Others 634 418 2.47 337 (81)
330.4 Land Easements 627 111 255 144
331.0 Structures & Improvements 911 061 093 093
332.0 Reservoirs, Dams & Waterways 010 780 178 765 663 (103,102)
332.2 Reservoirs, Dams & Waterways-Recreation 366 516 250 (266)
333.0 Waterwheels, Turbines & Generators 968 823 300 035 241 (279 794)
334.0 Accessory Electric Equipment 706 235 117 833 868 (101 965)
335.0 Misc. Power Plant Equipment 136,815 990 614 376)
Total 965,341 693 884 199,321 (494 563)
LONG LAKE
330.3 Removing Property of Others 171 080 535 3,490 045)
330.4 Land Easements 246 562 536 005 469
331.0 Structures & Improvements 436 183 (1.258)723 981
331.1 Structures & Improvements-Fish & Wildlife 872
331.2 Structures & Improvements-Recreation 158
332.0 Reservoirs, Dams & Waterways 532.371 940 642 181 856 (758 786)
332.2 Reservoirs, Dams & Waterways-Recreation 105 639 011 384 627)
333.0 Waterwheels, Turbines & Generators 823 605 512 778 113 825 (398,953)
334.0 Accessory Electric Equipment 779 392 203 025 791 (180,234)
335.0 Misc. Power Plant Equipment 387 918 216 129 (12 087)
Total 639 780 690,485 345,203 345 282)
MONROE STREET
331.0 Structures & Improvements 742 077 145 140 906 134 761
331.1 Structures & Improvements-Fish & Wildlife 206 2.43
331.2 Structures & Improvements-Recreation 507 701 403 743 340
332.0 Reservoirs. Dams & Waterways 045 079 006 138 375 134 369
333.0 Waterwheels, Turbines & Generators 018 005 734 251 211 239 477
334.0 Accessory Electric Equipment 660 800 167 326 159
335.0 Misc. Power Plant Equipment 344 103 537 434
336.0 Roads, Railroads & Bridges 50,448 095 045
Total 050,660 608 594 198 565,590
ATTACHMENT B
Page 2 of 7
Case Nos. A VU-07-111A VU-07-
ORDER NO. 30498
ATTACHMENT B
AVISTA UTILITIES
Depreciation Expense
For the Year Ended December 31 2006
(1 J (2)(3)(4)(5)(6)(7)
Existing Proposed
Account 2006 Avg.Existing Annual Study Annual Increase or
Number Descri tion Balance Rate Deprec.Rate Deprec.(Decrease)
NINE MILE
330.3 Removing Property of Others 937 394 165 (229)
330.4 Land Easements 980
331.0 Structures & Improvements 934 864 218 469 251
332.0 Reservoirs, Dams & Waterways 744 264 230 078 253 676 23,598
332.1 Reservoirs, Dams & Waterways-Fish & Wildlife 535
332.2 Reservoirs , Dams & Waterways-Recreation 92,744 817 179 362
333.0 Waterwheels, Turbines & Generators 465,050 459 286 791 256 332
334.0 Accessory Electric Equipment 643,763 847 945 098
335.0 Misc. Power Plant Equipment 281 963 856 513 (343)
336.0 Roads , Railroads & Bridges 625 181 144 16,505 361
Total 802 281 1.43 412 921 726,368 313 447
NOXON RAPIDS
330.3 Removing Property of Others 413 622 122 586 594 155 471 569
330.4 Land Easements 10,607 300 256
330.41 Land Easements-Conservation 550,000 292 10,120 828
331.0 Structures & Improvements 080 010 233 184 196,116 (37 068)
331.1 Structures & Improvements-Fish & Wildlife 28,422 179 523 344
331.2 Structures & Improvements-Recreation 574 838 692 635 (57)
331.26 Structures & Improvements-Rec Info 359 242 211 (31)
332.0 Reservoirs, Dams & Waterways 097 050 536 877 538,737 860
332.1 Reservoirs, Dams & Waterways-Fish & Wildlife 005 322 933 794 (139)
332.15 Reservoirs, Dams & Waterways-Fish & Wildlife 481 128 583 468 (115)
332.2 Reservoirs, Dams & Waterways-Recreation 96,606 615 087 472
333.0 Waterwheels, Turbines & Generators 241 997 238,057 960 694 722 637
334.0 Accessory Electric Equipment 692 253 101 873 321 114 219 241
335.0 Misc. Power Plant Equipment 300,093 136,474 311 (114 163)
335.1 Misc. Power Plant Equipment-Fish & Wildlife 348 557 854 1.40 880 (15 974)
335.2 Misc. Power Plant Equipment-Recreation 753 1.40
336.0 Roads, Railroads & Bridges . 225 369 632 778 (854)
Total 122 163 986 1,437 143 693 017 255,874
POST FALLS
330.3 Removing Property of Others 167 368 968 600
330.4 Land Easements 708 437 978 102 650 59,672
331.0 Structures & Improvements 612 088 204 204
331.1 Structures & Improvements-Fish & Wildlife 665
331.2 Structures & Improvements-Recreation 526
332.0 Reservoirs, Dams & Waterways 759,792 22,685 156,666 133,981
332.1 Reservoirs, Dams & Waterways-Fish & Wildlife 133 461 397
332.2 Reservoirs , Dams & Waterways-Recreation 268,670 064 302 238
333.0 Waterwheels, Turbines & Generators 230,774 569 569
334.0 Accessory Electric Equipment 854 367 196 196
335.0 Misc. Power Plant Equipment 214 663 159 753 594
Total 696 282 318 281 789 211 471
UPPER FALLS
330.3 Removing Property of Others 564 284 2.48 576 (708)
331.0 Structures & Improvements 460 413
331.2 Structures & Improvements-Recreation 387
332.0 Reservoirs, Dams & Waterways 058 533 119 694 702 (34 992)
332.2 Reservoirs, Dams & Waterways-Recreation 644 077 838 239)
333.0 Waterwheels, Turbines & Generators 090 002 706 810 (66,896)
334.0 Accessory Electric Equipment 776 139 327 359 (14 968)
335.0 Misc. Power Plant Equipment 106 857 855 2,458 603
Total 648,539 2.41 232,943 113 743 (119,200)
Total Hydraulic Production Plant 328 837 318 208,517 629,652 421 135
ATTACHMENT B
Page 3 of 7
Case Nos. A VU-07-11/A VU-07-
ORDER NO. 30498
ATTACHMENT B
AVISTA UTILITIES
Depreciation Expense
For the Year Ended December 31 , 2006
(1)(2)(31 (41 (5)(6)(7)
Existing Proposed
Account 2006 Avg.Existing Annual Study Annual Increase or
Number Description Balance Rate Depree.Rate Depree.(Decrease)
OTHER PRODUCTION PLANT
BOULDER PARK
341.0 Structures & Improvements 724 602 230 057 (17 173)
342.0 Fuel Holders, Producers & Access.115 970 799 143 656)
343.0 Prime Movers 216 861 722 139)
344.0 Generators 093,374 245 866 854 652 (391 214)
345.0 Accessory Electric Equipment 261 612 081 770 311)
346.0 Miscellaneous Equipment 961 431 187 (244)
Total 259,735 304 268 886,531 (417 737)
COYOTE SPRINGS
341.0 Structures & Improvements 381 703 474 265 314 135 (160 130)
342.0 Fuel Holders, Producers & Access.19,271 114 803 041 549 227 (253 814)
344.0 Generators 116,479 939 818 187 401,214 416 973)
345.0 Accessory Electric Equipment 564 443 528 252 389,498 (138,754)
346.0 Miscellaneous Equipment 001 553 706 643 (14 063)
Total 160,698 752 665,451 681 717 983,734)
KETTLE FALLS
342.0 Fuel Holders, Producers & Access.89,232 721 230 509
343.0 Prime Movers 071 493 379 188 427 267 079
344.0 Generators 718 185 104
345.0 Accessory Electric Equipment 894 206 4.48 219
Total 169,337 383,196 431 901 705
NORTHEAST TURBINE
341.0 Structures & Improvements 256,733 992 516 476)
342.0 Fuel Holders, Producers & Access,460 654 412 (242)
343.0 Prime Movers 089 743 200 883 711,727 510,844
344.0 Generators 595 127 16,623 685 062
345.0 Accessory Electric Equipment 337 809 795 849 054
346.0 Miscellaneous Equipment 244 881 494 037 457)
Total 555 753 253,441 765,225 511 784
RATHDRUM TURBINE
341.0 Structures & Improvements 186 951 125 885 125 885 (0)
342.0 Fuel Holders, Producers & Access.700 144 295 706 411
343.0 Prime Movers 658,328 132 066 132 066 (0)
344.0 Generators 574 276 636 953 636,953
345.0 Accessory Electric Equipment 871 631 623 66,630
Total 991 330 018 822 031,239 417
Total Other Production Plant 272 674 907 10,625 178 796,613 828 565)
TOTAL GENERATION 974 226 256 28,222 210 25,601,216 620,994)
ATTACHMENT B
Page 4 of 7
Case Nos. A VU-07-111A VU-07-
ORDER NO. 30498
ATTACHMENT B
AVISTA UTILITIES
Depreciation Expense
For the Year Ended December 31 , 2006
(1)(21 (3)(4)(5)(6)(7)
Existing Proposed
Account 2006 Avg.Existing Annual Study Annual Increase or
Number Description Balance Rate Depree.Rate Depree.(Decrease)
TRANSMISSION PLANT
350.3 Removing Property of Others 1,486 017 616 724 (892)
350.4 Land Rights 8,487 996 111 933 108 646 287)
352.0 Structures & Improvements 13,150,989 277 905 211 731 (66,174)
353.0 Station Equipment 153,279 410 026 986 663,378 (363 608)
354.0 Towers & Fixtures 069 239 1.40 238 969 319,195 226
355.0 Poles & Fixtures 291 514 010 571 826,964 (1,183,607)
356.0 OH Conductor & Devices 726 141 309,942 403 615 673
357.0 UG Conduit 561 148 315 866 (449)
358.0 UG Conductor & Devices 317 910 032 800 768
359.0 Roads & Trails 826 844 480 143 663
Total 369,197 208 049,749 614,061 1,435,688
DISTRIBUTION PLANT
361.0 Structures & Improvements 229,439 217 919 184 130 (33 789)
362.0 Station Equipment 76,759,289 2.48 900,202 995 742 540
364.0 Poles, Towers & Fixtures 171 634,479 210 542 565 477 354 935
365.0 OH Conductor & Devices 113 570 904 477,444 2.46 793 844 316,400
366.0 UG Conduit 876 655 128 211 622 657 494 446
367-WA UG Conductor & Devices 063,858 363 965 771 749 407 784
367-ID UG Conductor & Devices 356 657 780 733 456 722 675,989
368.0 Line Transformers 134 753,556 573 305 695 071 (878 234)
369.1 OH Services 41,413,068 882,085 699 881 (182,204)
369.2 UG Services - Spokane Network 229 912 165 556 609)
369.3 UG Services - Other 118 269 152 875 860,480 (292 395)
370.0 Meters 761 590 779 704 567 902 (211 802)
373.1 Street Lighting & Signal Sys-Mercury Vapor 841 917 107 016 293 (54 723)
373.2 Street Lighting & Signal Sys-UG Conductor 432 780 870 923 (23,947)
373.3 Street Lighting & Signal Sys-Decorative 233 275 115 621 379 (62 242)
373.4 Street Lighting & Signal Sys-Sodium Vapor 368 277 687,777 320 585 (367 192)
Total 805 643,925 457,434 689 392 231,958
148 185
ELECTRIC GENERAL PLANT Utility 0
390.1 Structures & Improvements 033 059 008 612 396)
391.1 Computer Equipment 148 900 20.321 17.311 010)
393.0 Stores Equipment 104 872 2.40 516 360 (156)
394.0 Tools, Shop & Garage Equipment 874 999 4.49 129 084 121 325 759)
395.0 Laboratory Equipment 047 117 101,783 235,237 133 454
397.0 Communication Equipment 27,186,860 683 888 5.40 468,090 215 798)
398.0 Miscellaneous Equipment 760
Total 35,398,567 988,605 891 000 097 605)
ELECTRIC TRANSPORTATION PLANT Utility 0
392.0 Transportation Equipment 243,320 (3.38)(41 966)003 969
396.0 Power Operated Equipment 449 252 7.43 181 921 134 954 (46 967)
Total 692 572 139 955 180 957 002
TOTAL ELECTRIC PLANT 188 158 528 857 953 976 626 (881 327)
ATTACHMENT B
Page 5 of 7
Case Nos. A VU-07-11/A VU-07-
ORDER NO. 30498
ATTACHMENT B
AVISTA UTILITIES
Depreciation Expense
For the Year Ended December 31, 2006
(1)(2)(3)(41 (5)(6)(7)
Existing Proposed
Account 2006 Avg.Existing Annual Study Annual Increase or
Number Description Balance Rate Depree.Rate Depree.(Decrease)
COMMON PLANT
GENERAL PLANT Utility 7
390.1 Structures & Improvements 112 759 465 996 464 586 (1,410)
391.0 Office Furniture & Equipment 332 392 289 007 609 176 320 169
391.1 Computer Equipment 587,875 20.176,513 19.099,576 (76 937)
391.7 Office Furniture & Equipment-Lease 106 109 140,707 114 926 (25 781)
394.0 Tools, Shop & Garage Equipment 607 942 378 25,838 540)
395.0 Laboratory Equipment 732 3.46 140 967 (173)
397.0 Communication Equipment 566,930 445,689 330 646 (115,043)
397.2 Communication Equipment-Portable 574 11.980 697 283)
397.7 Communication Equipment-Lease 515 853 50,657 760 103
398.0 Miscellaneous Equipment 614 070 836 704 868
Total 569 236 625 903 745,875 119 972
GENERAL PLANT Utility 9
389.3 Removing Property of Others 277 677 293 (384)
389.4 Land Easements 787 066 253 187
390.1 Structures & Improvements 340,853 167 757 154 306 (13 451)
393.0 Stores Equipment 950 549 2.41 907 608 701
394.0 Tools, Shop & Garage Equipment 356,632 042 157 (885)
395.0 Laboratory Equipment 767 259 629 25,089 (540)
397.0 Communication Equipment 026 217 690 073 508 698 (181 375)
397.2 Communication Equipment-Portable 910 752 11.105 125 039 (34 086)
398.0 Miscellaneous Equipment 615 768 501 733
Total 18,437 941 030 044 807 944 (222 100)
TRANSPORTATION PLANT Utility 7
392.0 Transportation Equipment 502 394 810 (584)
396.0 Power Operated Equipment 554 036 7.43 165 746 419)
Total 601 538 559 33,556 (10 003)
TRANSPORTATION PLANT Utility 9
392.0 Transportation Equipment 285,199 14,039 866 173)
396.0 Power Operated Equipment 487 024 7.43 186 906 (8,280)
Total 772 223 50,225 773 (11,452)
TOTAL COMMON PLANT 380,938 749 731 626,147 (123,584)
A TT A CHMENT B
Page 6 of 7
Case Nos. A VU-07-11/A VU-07-
ORDER NO. 30498
ATTACHMENT B
AVISTA UTILITIES
Depreciation Expense
For the Year Ended December 31 2006
(1)(2)(3)(4)(5)(6)(71
Existing Proposed
Account 2006 Avg.Existing Annual Study Annual Increase or
Number Description Balance Rate Depree.Rate Depree.(Decrease)
GAS PLANT
UNDERGROUND STORAGE
350.2 Rights of Way 723 655 553 (102)
351.0 Structures & Improvements 065,109 633 1.44 15,338 (3,295)
352.0 Storage Wells 817 514 116 348 100 643 (15,705)
352.1 Wells 254 354 453 340 113)
352.2 Reservoirs 203 330 514 778 264
352.3 Cushion Natural Gas 971,926 151 687 112 272 (39,415)
353.0 Lines 823,423 962 19,433 471
354.0 Compressor Station Equipment 043,859 47,484 36,994 (10 490)
355.0 Measuring & Regulating Equipment 171 919 573 390 817
356.0 Purification Equipment 407 250 095 570 525)
357,0 Other Equipment 681,643 46,583 801 (12 782)
Total 18,473,050 425 987 344 112 (81 875)
DISTRIBUTION PLANT
375.0 Structures & Improvements 518 673 375 166 209)
376.0 Mains 160 645 516 833 236 907,684 (925 552)
378.0 Measuring/Regulating Station Equipment 511 639 878 107 456 578
379.0 Measuring/Regulating City Gate Equipment 1,491 098 399 45,926 527
380.0 Services 117 362,693 132 926 250,947 118 021
381.0 Meters 199,504 721 937 197,824 475 887
385.0 Measuring/Regulating Industrial Equipment 263,561 2.44 124 876 (13 248)
Total 322 992 684 862 875 561 878 (300 997)
GAS GENERAL PLANT
390.1 Structures & Improvements 605 452 15,653 921 268
393.0 Stores Equipment 900 2.48 412 236 824
394.0 Tools, Shop & Garage Equipment 567 219 464 503 039
395.0 Laboratory Equipment 553,814 110 143 033
397.0 Communication Equipment 771 590 382 641 (41 741)
398.0 Miscellaneous Equipment 332 401 376 (25)
Total 586 307 177 422 152,821 (24 601)
GAS TRANSPORTATION PLANT
392.0 Transportation Equipment 286,905 334 345
396.0 Power Operated Equipment 144 449 7.44 113 70,727 (14 386)
Total 431 354 447 85,072 (14,375)
COMMON GAS GENERAL PLANT Utility 8
391.0 Office Furniture & Equipment 378 871 163 447 284
394.0 Tools, Shop & Garage Equipment 142 360 879 275 396
395.0 Laboratory Equipment 266 565 4.49 775 210
397.0 Communication Equipment 864 974 10.90,994 373 (46,621)
Total 1,403 471 114 601 88,870 (25 731)
TOTAL GAS PLANT 347 886 866 680 332 232 753 (447 579)
GRAND TOTAL 607 426 332 288 016 69,835 527 (1,452 489)
ATTACHMENT B
Page 7 of 7
Case Nos. A VU-07-111A VU-07-
ORDER NO. 30498