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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
 WASHINGTON, D.C. 20549
 FORM 10-K
  þ
    
    Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
 For the fiscal year ended December 31, 2009
 or
 o
    
    Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
 For the transition period from _____________________ to _________________________
 Commission File Number 1-7414
 NORTHWEST PIPELINE GP
  DELAWARE
(State or other jurisdiction of 
incorporation or organization)
    
    26-1157701
(I.R.S. Employer
Identification No.)295 Chipeta Way, Salt Lake City, Utah
(Address of principal executive offices)
    
    84108
(Zip Code)
 
 
 
 o þ
 o þ
 þ o
 o o
 þ
  Large accelerated filer o
    
    Accelerated filer o
    

Non-accelerated filer þ
(Do not check if a smaller Reporting company)
    
    Smaller reporting company o
 o þ




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TABLE OF CONTENTS
 Heading
    
    
    
    PagePART IItem 1.
    
    BUSINESS
    
    
    1Item 1A.
    
    RISK FACTORS
    
    
    10Item 1B.
    
    UNRESOLVED STAFF COMMENTS
    
    
    24Item 2.
    
    PROPERTIES
    
    
    24Item 3.
    
    LEGAL PROCEEDINGS
    
    
    24Item 4.
    
    SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS
    
    
    24PART IIItem 5.
    
    MARKET FOR REGISTRANTS COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES
    
    
    25Item 6.
    
    SELECTED FINANCIAL DATA
    
    
    25Item 7.
    
    MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
    
    
    26Item 7A.
    
    QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK
    
    
    38Item 8.
    
    FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA
    
    
    40Item 9.
    
    CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE
    
    
    67Item 9A(T).
    
    CONTROLS AND PROCEDURES
    
    
    67Item 9B.
    
    OTHER INFORMATION
    
    
    68PART IIIItem 10.
    
    DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE
    
    
    69Item 11.
    
    EXECUTIVE COMPENSATION
    
    
    70Item 12.
    
    SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS
    
    
    72Item 13.
    
    CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE
    
    
    72Item 14.
    
    PRINCIPAL ACCOUNTING FEES AND SERVICES
    
    
    74PART IVItem 15.
    
    EXHIBITS, FINANCIAL STATEMENT SCHEDULES
    
    
    76EX-12EX-23EX-24EX-31.AEX-31.BEX-32.A
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##### Table of Contents



NORTHWEST PIPELINE GP
 FORM 10-K
 
 PART I
 
 Item 1.
    
    BUSINESS
 GENERAL
      PIPELINE SYSTEM, CUSTOMERS AND COMPETITION
 Transportation and Storage
  
 *
    
    The term Mcf means thousand cubic feet, MMcf means million cubic
feet and Bcf means billion cubic feet. All volumes of natural gas are
stated at a pressure base of 14.73 pounds per square inch absolute at 60 degrees
Fahrenheit. The term MMBtu means one million British Thermal Units and TBtu means one
trillion British Thermal Units. The term Dth means one dekatherm, which is equal to one MMBtu.
The term MDth means thousand dekatherms. The term MMDth means million dekatherms. 1




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
    
    Jackson Prairie:We own a one-third interest in the Jackson Prairie underground storage
facility located near Chehalis, Washington, with the remaining interests owned by two of our
distribution customers. As of December 31, 2009, our share of the firm seasonal storage
service in this facility was approximately 7.7 Bcf of working natural gas storage capacity
and up to 383 MMcf* per day of peak day deliveries. Additionally, our share of the
best-efforts delivery capacity was 50 MMcf per day. As described below, we are participating
in an ongoing expansion of Jackson Prairie.
 
    
    Plymouth LNG:We also own and operate a Liquefied Natural Gas (LNG) storage facility
located near Plymouth, Washington, which provides standby service for our customers during
extreme peaks in demand. The facility has a total LNG storage capacity equivalent to 2.3 Bcf
of working natural gas, liquefaction capability of 12 MMcf per day and regasification
capability of 300 MMcf per day. Certain of our major customers own the working natural gas
stored at the LNG plant.
 
    
    Clay Basin Field:We have a contract with a third party under which we contract for
natural gas storage services in an underground storage reservoir in the Clay Basin Field
located in Daggett County, Utah. We are authorized to utilize the Clay Basin Field at a
seasonal storage level of 3.0 Bcf of working natural gas, with a firm delivery capability of
25 MMcf of natural gas per day.
 Competition
  2




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Supply and Demand Dynamics
  Customers
  3




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CAPITAL PROJECTS
  Colorado Hub Connection Project
    Jackson Prairie Underground Expansion
    Sundance Trail Expansion
  4




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OPERATING STATISTICS
 Throughput
  Year Ended December 31,2009
    
    
    2008
    
    
    2007(In trillion British Thermal Units)Total Throughput (1)
    
    
    769
    
    
    
    781
    
    
    
    757Average Daily Transportation Volumes
    
    
    2.1
    
    
    
    2.1
    
    
    
    2.1Average Daily Reserved Capacity Under Base Firm
Contracts, excluding peak capacity
    
    
    2.7
    
    
    
    2.5
    
    
    
    2.5Average Daily Reserved Capacity Under Short-Term
Firm Contracts (2)
    
    
    .5
    
    
    
    .7
    
    
    
    .8
 
 (1)
    
    Parachute Lateral volumes of 49 TBtu in 2009, 102 TBtu in 2008 and 55 TBtu in 2007 are
excluded from total throughput as these volumes flowed under separate contracts that do not
result in mainline throughput.(2)
    
    Includes additional capacity created from time to time through the installation of new
receipt or delivery points or the segmentation of existing mainline capacity. Such capacity
is generally marketed on a short-term firm basis. Seasonality
  Jan-Mar
    
    
    Apr-Jun
    
    
    Jul-Sep
    
    
    Oct-Dec
    
    
    Total2009Revenues ($ in 000)
    
    $
    111,548
    
    
    $
    107,756
    
    
    $
    106,615
    
    
    $
    108,460
    
    
    $
    434,379Revenue %
    
    
    25.7
    %
    
    
    24.8
    %
    
    
    24.5
    %
    
    
    25.0
    %
    
    
    100
    %Operating Expenses ($ in 000)
    
    $
    58,396
    
    
    $
    60,743
    
    
    $
    57,470
    
    
    $
    57,261
    
    
    $
    233,870Throughput (TBtu) (1)
    
    
    224
    
    
    
    173
    
    
    
    166
    
    
    
    206
    
    
    
    769Throughput %
    
    
    29.1
    %
    
    
    22.5
    %
    
    
    21.6
    %
    
    
    26.8
    %
    
    
    100
    %
 
 (1)
    
    Parachute Lateral volumes are excluded from throughput as these volumes flowed under separate
contracts that do not generally result in mainline throughput. REGULATORY MATTERS
 FERC Regulation
  
    
    transportation and storage of natural gas;
 
    
    rates and charges;
 5




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
    
    terms of service including creditworthiness requirements;
 
    
    construction of new facilities;
 
    
    extension or abandonment of service and facilities;
 
    
    accounts and records;
 
    
    depreciation and amortization policies;
 
    
    relationships with gas marketing functions within Williams; and
 
    
    initiation and discontinuation of services.
        Energy Policy Act of 2005
  6




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Safety and Maintenance
    Environmental Regulation
   7




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
    
    requiring the acquisition of permits to conduct regulated activities;
 
    
    restricting the manner in which we can release materials into the environment;
 
    
    imposing investigatory and remedial obligations to mitigate pollution from
former or current operations;
 
    
    assessing administrative, civil, and criminal penalties for failure to comply
with applicable legal requirements; and
 
    
    in certain instances, enjoining some or all of the operations of facilities
deemed in non-compliance with permits issued pursuant to applicable laws and
regulations.
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INSURANCE
  EMPLOYEES
  TRANSACTIONS WITH AFFILIATES
  
 Item 1A.
    
    RISK FACTORS
 FORWARD LOOKING STATEMENTS/RISK FACTORS AND CAUTIONARY STATEMENT FOR 
PURPOSES OF THE SAFE
HARBOR
PROVISIONS OF
 THE PRIVATE SECURITIES LITIGATION REFORM ACT OF 1995
   
    
    Amounts and nature of future capital expenditures;
 
    
    Expansion and growth of our business and operations;
 
    
    Financial condition and liquidity;
 
    
    Business strategy;
 
    
    Cash flow from operations or results of operations;
 10




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
    
    Rate case filings; and
 
    
    Natural gas prices and demand.
  
    
    Availability of supplies (including the uncertainties inherent in assessing and
estimating future natural gas reserves), market demand, volatility of prices, and the
availability and cost of capital;
 
    
    Inflation, interest rates, and general economic conditions (including future
disruptions and volatility in the global credit markets and the impact of these
events on our customers and suppliers);
 
    
    The strength and financial resources of our competitors;
 
    
    Development of alternative energy sources;
 
    
    The impact of operational and development hazards;
 
    
    Costs of, changes in, or the results of laws, government regulations (including
proposed climate change legislation), environmental liabilities, litigation and rate
proceedings;
 
    
    Our costs for defined benefit pension plans and other postretirement benefit
plans;
 
    
    Changes in maintenance and construction costs;
 
    
    Changes in the current geopolitical situation;
 
    
    Our exposure to the credit risk of our customers;
 
    
    Risks related to strategy and financing, including restrictions stemming from our
debt agreements, future changes in our credit ratings and the availability and cost
of credit;
 
    
    Risks associated with future weather conditions;
 
    
    Acts of terrorism; and
 
    
    Additional risks described in our filings with the Securities and Exchange
Commission (SEC).
    11




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RISK FACTORS
  Risks Inherent to our Industry and Business
 Our natural gas transportation and storage activities involve numerous risks that might result in
accidents and other operating risks and hazards .
  
    
    fires, blowouts, cratering and explosions;
    
    uncontrolled releases of natural gas;
    
    pollution and other environmental risks;
    
    natural disasters;
    
    aging pipeline infrastructure and mechanical problems;
    
    damages to pipelines and pipeline blockages;
    
    operator error;
    
    damage inadvertently caused by third party activity, such as operation of
construction equipment; and
    
    terrorist attacks or threatened attacks on our facilities or those of other energy
companies.
  Increased competition from alternative natural gas transportation and storage options and
alternative fuel sources could have a significant financial impact on us.
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We may not be able to maintain or replace expiring natural gas transportation and storage contracts
at favorable rates or on a long-term basis.
   
    
    the level of existing and new competition to deliver natural gas to our markets;
    
    the growth in demand for natural gas in our markets;
    
    whether the market will continue to support long-term firm contracts;
    
    whether our business strategy continues to be successful;
    
    the level of competition for natural gas supplies in the production basins serving
us; and
    
    the effects of state regulation on customer contracting practices.
  Competitive pressures could lead to decreases in the volume of natural gas contracted or
transported through our pipeline system.
  13




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Any significant decrease in supplies of natural gas in our areas of operation could adversely
affect our business and operating results.
    Decreases in demand for natural gas could adversely affect our business.
  Significant prolonged changes in natural gas prices could affect supply and demand and cause a
termination of our transportation and storage contracts or a reduction in throughput on our system.
  14




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Some portions of our current pipeline infrastructure and other assets have been in use for many
decades, which may adversely affect our business.
  We are subject to risks associated with climate change.
  Our operations are subject to governmental laws and regulations relating to the protection of the
environment, including those relating to climate change, which may expose us to significant costs
and liabilities and could exceed our current expectations.
     15




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We may be subject to legislative and regulatory responses to climate change with which compliance
may be costly.
   The failure of new sources of natural gas production or LNG import terminals to be successfully
developed in North America could increase natural gas prices and reduce the demand for our
services.
  16




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We depend on certain key customers for a significant portion of our revenues. The loss of any of
these key customers or the loss of any contracted volumes could result in a decline in our
business.
  We are exposed to the credit risk of our customers, and our credit risk management may not be
adequate to protect against such risk.
  If third-party pipelines and other facilities interconnected to our pipeline and facilities become
unavailable to transport natural gas, our revenues could be adversely affected.
  We do not own all of the land on which our pipeline and facilities are located, which could disrupt
our operations.
  17




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We do not insure against all potential losses and could be seriously harmed by unexpected
liabilities or by the inability of the insurers we do use to satisfy our claims.
    Execution of our capital projects subjects us to construction risks, increases in labor costs and
materials, and other risks that may adversely affect financial results.
  
    
    the ability to obtain necessary approvals and permits by regulatory agencies on a
timely basis and on acceptable terms;
    
    the availability of skilled labor, equipment, and materials to complete expansion
projects;
    
    potential changes in federal, state and local statutes and regulations, including
environmental requirements, that prevent a project from proceeding or increase the
anticipated cost of the project;
    
    impediments on our ability to acquire rights-of-way or land rights on a timely basis
and on acceptable terms;
    
    the ability to construct projects within estimated costs, including the risk of cost
overruns resulting from inflation or increased costs of equipment, materials, labor or
other factors beyond our control, that may be material; and
 18




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
    
    the ability to access capital markets to fund construction projects.
  Potential changes in accounting standards might cause us to revise our financial results and
disclosures in the future, which might change the way analysts measure our business or financial
performance.
  Risks Related to Strategy and Financing
 Our debt agreements and Williams and WPZs public indentures contain financial and operating restrictions
that may limit our access to credit and affect our ability to operate our business. In addition,
our ability to obtain credit in the future will be affected by Williams and WPZs credit ratings.
     19




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Future disruptions in the global credit markets may make debt markets less accessible, create a
shortage in the availability of credit and lead to credit market volatility.
  Adverse economic conditions could negatively affect our results of operations.
  A downgrade of our credit ratings could impact our liquidity, access to capital and our costs of
doing business, and maintaining our credit ratings is under the control of independent third
parties.
  
    
    economic downturns;
    
    deteriorating capital market conditions;
    
    declining market prices for natural gas;
    
    terrorist attacks or threatened attacks on our facilities or those of other energy
companies;
    
    the overall health of the energy industry, including the bankruptcy or insolvency of
other companies.
  20




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Williams can exercise substantial control over our distribution policy and our business and
operations and may do so in a manner that is adverse to our interests.
  
    
    payment of distributions and repayment of advances;
    
    decisions on financings and our capital raising activities;
    
    mergers or other business combinations; and
    
    acquisition or disposition of assets.
  Risks Related to Regulations that Affect our Industry
 Our natural gas transportation and storage operations are subject to regulation by FERC, which
could have an adverse impact on our ability to establish transportation and storage rates that
would allow us to recover the full cost of operating our pipeline, including a reasonable rate of
return.
  
    
    transportation of natural gas in interstate commerce;
    
    rates, operating terms and conditions of service, including initiation and
discontinuation of services;
    
    the types of services we may offer to our customers;
    
    certification and construction of new facilities;
    
    acquisition, extension, disposition or abandonment of facilities;
    
    accounts and records;
    
    depreciation and amortization policies;
    
    relationships with marketing functions within Williams  involved in certain aspects of the
natural gas business; and
    
    market manipulation in connection with interstate sales, purchases or transportation
of natural gas.
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We could be subject to penalties and fines if we fail to comply with FERC regulations.
  The outcome of future rate cases to set the rates we can charge customers on our pipeline might
result in rates that lower our return on the capital that we have invested in our pipeline.
  The outcome of future rate cases will determine the amount of income taxes that we will be allowed
to recover.
  Legal and regulatory proceedings and investigations relating to the energy industry and capital
markets have adversely affected our business and may continue to do so.
   22




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Risks Related to Employees, Outsourcing of Non-Core Support Activities, and Technology.
 Institutional knowledge residing with current employees nearing retirement eligibility might not be
adequately preserved.
  Failure of or disruptions to our outsourcing relationships might negatively impact our ability to
conduct our business.
   Our allocation from Williams for costs for its defined benefit pension plans and other
postretirement benefit plans are affected by factors beyond our and Williams control.
  Risks Related to Weather, Other Natural Phenomena and Business Disruption
 Our assets and operations can be affected by weather and other natural phenomena.
  23




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Acts of terrorism could have a material adverse effect on our financial condition, results of
operations and cash flows.
  
 Item 1B.
    
    UNRESOLVED STAFF COMMENTS
  
 Item 2.
    
    PROPERTIES
  
 Item 3.
    
    LEGAL PROCEEDINGS
  
 Item 4.
    
    SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS
  24




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PART II
 
 Item 5.
    
    MARKET FOR REGISTRANTS COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF
EQUITY SECURITIES
     
 Item 6.
    
    SELECTED FINANCIAL DATA
  Year Ended December 31,2009
    
    2008
    
    2007
    
    2006
    
    2005(Restated) (B)
    
    (Restated) (B)
    
    (Restated) (B)
    
    (Restated) (B)(Thousands of Dollars)Income Statement Data:Operating revenues
    
    $
    434,379
    
    
    $
    434,854
    
    
    $
    421,851
    
    
    $
    324,250
    
    
    $
    321,457Net income
    
    
    153,651
    
    
    
    155,371
    
    
    
    439,726
    (A)
    
    
    54,462
    
    
    
    68,974Balance Sheet Data (at
period end):Total assets
    
    
    2,081,277
    
    
    
    2,078,812
    
    
    
    2,033,596
    
    
    
    2,034,748
    
    
    
    1,661,324Long-term debt, including
current maturities
    
    
    693,437
    
    
    
    693,240
    
    
    
    693,736
    
    
    
    687,075
    
    
    
    520,080Total owners equity
    
    
    1,207,150
    
    
    
    1,210,547
    
    
    
    1,177,098
    
    
    
    846,809
    
    
    
    728,505Cash Distributions
    
    
    135,000
    
    
    
    419,342
    
    
    
    109,770
    
    
    
    
    
    
    
    50,000
 Note:
    
    Earnings and distributions/dividends per partnership unit/common share are not presented for
2005 through 2009. We were a wholly-owned subsidiary of Williams at December 31, 2007 and for
all prior periods presented. Distributions for 2009 and 2008 were made to our partners based
upon each partnerships ownership interest.
 
 (A)
    
    Through September 30, 2007, we used the liability method of accounting for income taxes which
required, among other things, provisions for all temporary differences between the financial
basis and the tax basis in our assets and liabilities and adjustments to the existing deferred
tax balances for changes in tax rates. Following our conversion to a general partnership on
October 1, 2007, we are no longer subject to income tax. On October 1, 2007, we reversed
deferred income tax liabilities of approximately $311.8 million to income and $0.2 million of
deferred income tax assets to other comprehensive income.(B)
    
    Our financial statements have been restated as described in Item 8. Financial Statements and
Supplementary DataNotes to Consolidated Financial StatementsNote 2. Restatement.
Accordingly, our 2005, 2006, 2007, and 2008 selected financial data has been restated to
reflect 25




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the change in accounting treatment. The net impact of the balance sheet corrections
resulted in an adjustment to loans to affiliate which have been reclassified to equity. A reconciliation
between our original basis in our total assets and liabilities and the selected financial data
above follows: Year Ended December 31,2008
    
    
    2007
    
    
    2006
    
    
    2005(Thousands of Dollars)Consolidated Balance Sheets:Total assets, as previously reported
    
    $
    2,082,172
    
    
    $
    2,056,471
    
    
    $
    2,049,324
    
    
    $
    1,692,371Benefit plans correction
    
    
    3,360
    
    
    
    22,875
    
    
    
    14,576
    
    
    
    31,047Total assets, as restated
    
    $
    2,078,812
    
    
    $
    2,033,596
    
    
    $
    2,034,748
    
    
    $
    1,661,324Total owners equity, as previously
reported ,
    
    $
    1,184,714
    
    
    $
    1,185,616
    
    
    $
    857,945
    
    
    $
    756,346Net (increase) decrease of benefit
plans correction
    
    
    (25,833
    )
    
    
    8,518
    
    
    
    11,136
    
    
    
    27,841Total owners equity, as restated
    
    $
    1,210,547
    
    
    $
    1,177,098
    
    
    $
    846,809
    
    
    $
    728,505
 
 Item 7.
    
    MANAGEMENTS DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
 GENERAL
    RECENT DEVELOPMENTS
   26




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HOW WE EVALUATE OUR OPERATIONS
  
    
    the level of capacity reserved under our long-term firm transportation and storage
contracts;
    
    the level of revenues provided by our short-term firm and interruptible transportation
and storage services;
    
    our operating expenses; and
    
    our cash available for distribution.
 Long-Term Firm Service
  Short-Term Firm and Interruptible Servic
  Operating Expenses
  Cash Available for Distribution
  27




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FACTORS THAT IMPACT OUR BUSINESS
     OPERATIONS
  Transportation Services
  28




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Storage Services
  OUTLOOK
  
    
    We have no significant debt maturities until 2016.
    
    As of December 31, 2009, we have approximately $66.8 million of available cash from
return of advances made to affiliates and available capacity under our Credit Facility.
(See further discussion in Managements Discussion and Analysis of Financial Condition
and Results of Operations  Method of Financing.)
    
    A significant portion of our transportation and storage services are provided
pursuant to long-term firm contracts that obligate our customers to pay us monthly
capacity reservation fees regardless of the amount of pipeline or storage capacity
actually utilized by a customer.
  29




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CRITICAL ACCOUNTING POLICIES, ESTIMATES, JUDGMENTS AND SENSITIVITIES
  Regulatory Accounting
  Contingencies
  Environmental Liabilities
  RESULTS OF OPERATIONS
 Analysis of Financial Results
  Years Ended December 31, 2008 and 2009
   30




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Years Ended December 31, 2007 and 2008
       31




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CAPITAL RESOURCES AND LIQUIDITY
     SOURCES (USES) OF CASH
 Years Ended December 31,2009
    
    
    2008
    
    
    2007(Thousands of Dollars)Net cash provided (used) by:Operating activities
    
    $
    234,798
    
    
    $
    239,014
    
    
    $
    205,357Financing activities
    
    
    (83,608
    )
    
    
    (126,848
    )
    
    
    (142,523
    )Investing activities
    
    
    (151,133
    )
    
    
    (112,318
    )
    
    
    (63,826
    )Increase (decrease) in cash
and cash equivalents
    
    $
    57
    
    
    $
    (152
    )
    
    $
    (992
    )
 Operating Activities
  32




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Financing Activities
  
    
    We paid distributions of $135.0 million to our partners.
    
    We received $49.2 million in capital contributions from Williams for the CHC Project.
  
    
    We issued $250 million aggregate principal amount of 6.05 percent senior unsecured notes
due 2018.
    
    We repaid the $250 million borrowed under the Williams revolving credit agreement in
2007.
    
    We received proceeds of $300.9 million from the sale of partnership interest.
    
    We paid distributions of $419.3 million to our partners.
  
    
    We issued $185 million aggregate principal amount of 5.95 percent senior unsecured notes
due 2017.
    
    We borrowed $250 million under the Williams revolving credit agreement.
    
    We retired $175 million of 8.125 percent senior unsecured notes due 2010.
    
    We retired $250 million of 6.625 percent senior unsecured notes due 2007.
    
    We paid distributions of $109.8 million to Williams.
 Investing Activities
  
    
    Capital expenditures totaled $152.6 million, primarily related to normal maintenance and
compliance projects and the CHC Project.
  
    
    Capital expenditures totaled $88.5 million, primarily related to normal maintenance and
compliance and the expansion of the Jackson Prairie storage facility.
    
    We advanced $26.9 million to Williams.
  
    
    Capital expenditures totaled $156.8 million, primarily related to normal maintenance and
compliance.
    
    We received $79.8 million of proceeds from the sale of the Parachute Lateral to an
affiliate.
    
    We received $10.9 million repayment of advances made to Williams.
 33




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##### Table of Contents



METHOD OF FINANCING
 Working Capital
    Short-Term Liquidity
    Credit Agreement
   34




---



##### Table of Contents



Long-Term Financing
  35




---



##### Table of Contents



CAPITAL REQUIREMENTS
    CREDIT RATINGS
  Moodys Investors Service
    
    Baa2Standard and Poors
    
    BBB-Fitch Ratings
    
    BBB
     36




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##### Table of Contents



OTHER
 Contractual Obligations
  2010
    
    
    2011-2012
    
    
    2013-2014
    
    
    Thereafter
    
    
    TotalLong-term debt,
including current
portion:Principal
    
    $
    
    
    
    $
    
    
    
    $
    
    
    
    $
    695.0
    
    
    $
    695.0Interest
    
    
    44.4
    
    
    
    88.9
    
    
    
    88.9
    
    
    
    165.5
    
    
    
    387.7Operating leases
    
    
    2.3
    
    
    
    4.6
    
    
    
    4.5
    
    
    
    11.8
    
    
    
    23.2Purchase Obligations:Natural gas
purchase,
storage,
transportation and
construction
    
    
    27.1
    
    
    
    4.6
    
    
    
    4.1
    
    
    
    
    
    
    
    35.8Other
    
    
    0.1
    
    
    
    0.3
    
    
    
    0.3
    
    
    
    6.7
    
    
    
    7.4Other long-term
liabilities,
including current
portion (1)(2)
    
    
    1.5
    
    
    
    3.0
    
    
    
    3.3
    
    
    
    
    
    
    
    7.8Total
    
    $
    75.4
    
    
    $
    101.4
    
    
    $
    101.1
    
    
    $
    879.0
    
    
    $
    1,156.9
 
 (1)
    
    Does not include estimated settlement of asset retirement obligations. (Please see Item 8
Financial Statements and Supplementary Data  Notes to Consolidated Financial Statements:
Note 10. Asset Retirement Obligations.)(2)
    
    Does not include non-current regulatory liabilities comprised of negative salvage and other
postretirement benefits. (Please see Item 8. Financial Statements and Supplementary Data 
Notes to Consolidated Financial Statements: Note 11. Regulatory Assets and Liabilities.) Off-Balance Sheet Arrangements
  Impact of Inflation
  Environmental Matters
  37




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##### Table of Contents



Safety Matters
  Legal Matters
  Regulatory Proceedings
  CONCLUSION
  
 Item 7A.
    
    QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK
 Interest Rate Risk
  December 31, 2009Fixed rates on long-term debt:5.95% senior unsecured notes due 2017
    
    $
    185,0006.05% senior unsecured notes due 2018
    
    
    250,0007.00% senior unsecured notes due 2016
    
    
    175,0007.125% senior unsecured notes due 2025
    
    
    85,000695,000Unamortized debt discount
    
    
    1,563Total long-term debt
    
    $
    693,437
  38




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##### Table of Contents



Credit Risk
  Market Risk
  39




---



##### Table of Contents



Item 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA
 INDEX TO FINANCIAL STATEMENTS
 PageManagements annual report on internal control over financial reporting
    
    
    41Report of independent registered public accounting firm
    
    
    42Consolidated statements of income for the years ended December 31, 2009, 2008 and 2007
    
    
    43Consolidated balance sheets at December 31, 2009 and 2008
    
    
    44Consolidated statements of owners equity for the years ended December 31, 2009, 2008 and 2007
    
    
    46Consolidated statements of comprehensive income for the years ended December 31, 2009, 2008 and 2007
    
    
    47Consolidated statements of cash flows for the years ended December 31, 2009, 2008 and 2007
    
    
    48Notes to consolidated financial statements
    
    
    49
 40




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##### Table of Contents



MANAGEMENTS REPORT ON INTERNAL CONTROL OVER FINANCIAL REPORTING
   Internal
Control  Integrated Framework.
      41




---



##### Table of Contents



REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
       /s/ Ernst & Young 
 42




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##### Table of Contents



NORTHWEST PIPELINE GP
 
 CONSOLIDATED STATEMENTS OF INCOME
  Years Ended December 31,2009
    
    
    2008
    
    
    2007OPERATING REVENUES
    
    $
    434,379
    
    
    $
    434,854
    
    
    $
    421,851OPERATING EXPENSES:General and administrative
    
    
    64,657
    
    
    
    60,403
    
    
    
    65,772Operation and maintenance
    
    
    71,085
    
    
    
    72,831
    
    
    
    66,847Depreciation
    
    
    86,373
    
    
    
    86,184
    
    
    
    84,731Regulatory credits
    
    
    (2,403
    )
    
    
    (2,617
    )
    
    
    (3,663
    )Taxes, other than income taxes
    
    
    14,158
    
    
    
    16,875
    
    
    
    13,997Regulatory liability reversal
    
    
    
    
    
    
    
    
    
    
    (16,562
    )Total operating expenses
    
    
    233,870
    
    
    
    233,676
    
    
    
    211,122Operating income
    
    
    200,509
    
    
    
    201,178
    
    
    
    210,729OTHER INCOME  net:Interest income Affiliated
    
    
    74
    
    
    
    813
    
    
    
    2,983Other
    
    
    16
    
    
    
    6
    
    
    
    2,681Allowance for equity funds used during construction
    
    
    1,996
    
    
    
    812
    
    
    
    2,091Miscellaneous other expense, net
    
    
    (135
    )
    
    
    (8
    )
    
    
    (517
    )Contract termination income
    
    
    
    
    
    
    
    
    
    
    18,199Total other income   net
    
    
    1,951
    
    
    
    1,623
    
    
    
    25,437INTEREST CHARGES:Interest on long-term debt
    
    
    44,439
    
    
    
    42,290
    
    
    
    46,828Other interest
    
    
    5,414
    
    
    
    5,571
    
    
    
    5,585Allowance for borrowed funds used
during construction
    
    
    (1,044
    )
    
    
    (431
    )
    
    
    (1,306
    )Total interest charges
    
    
    48,809
    
    
    
    47,430
    
    
    
    51,107INCOME BEFORE INCOME TAXES
    
    
    153,651
    
    
    
    155,371
    
    
    
    185,059BENEFIT FOR INCOME TAXES (Note 7)
    
    
    
    
    
    
    
    
    
    
    (254,667
    )NET INCOME
    
    $
    153,651
    
    
    $
    155,371
    
    
    $
    439,726CASH DISTRIBUTIONS/DIVIDENDS
    
    $
    135,000
    
    
    $
    419,342
    
    
    $
    109,770
  43




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##### Table of Contents



NORTHWEST PIPELINE GP
 
 CONSOLIDATED BALANCE SHEETS
  December 31,2009
    
    
    
    2008(Restated)ASSETSCURRENT ASSETS:Cash and cash equivalents
    
    $
    402
    
    
    $
    345Advances to affiliate
    
    
    
    
    
    
    65,977Accounts receivable Trade
    
    
    40,442
    
    
    
    40,116Affiliated companies
    
    
    4,514
    
    
    
    1,230Materials and supplies, less reserves of $11 for 2009 and $111
for 2008
    
    
    9,960
    
    
    
    9,817Exchange gas due from others
    
    
    4,089
    
    
    
    17,000Exchange gas offset
    
    
    10,288
    
    
    
    Prepayments and other
    
    
    4,241
    
    
    
    5,985Total current assets
    
    
    73,936
    
    
    
    140,470PROPERTY, PLANT AND EQUIPMENT, at cost
    
    
    2,887,021
    
    
    
    2,765,520Less  Accumulated depreciation
    
    
    950,708
    
    
    
    901,613Total property, plant and equipment, net
    
    
    1,936,313
    
    
    
    1,863,907OTHER ASSETS:Deferred charges
    
    
    13,996
    
    
    
    18,853Regulatory assets
    
    
    57,032
    
    
    
    55,582Total other assets
    
    
    71,028
    
    
    
    74,435Total assets
    
    $
    2,081,277
    
    
    $
    2,078,812
  44




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##### Table of Contents



NORTHWEST PIPELINE GP
 CONSOLIDATED BALANCE SHEETS
  December 31,2009
    
    
    
    2008(Restated)LIABILITIES AND OWNERS EQUITYCURRENT LIABILITIES:Accounts payable Trade
    
    $
    17,552
    
    
    $
    12,172Affiliated companies
    
    
    12,136
    
    
    
    6,484Accrued liabilities Taxes, other than income taxes
    
    
    8,176
    
    
    
    10,019Interest
    
    
    4,045
    
    
    
    4,045Employee costs
    
    
    9,435
    
    
    
    10,426Exchange gas due to others
    
    
    14,377
    
    
    
    12,165Exchange gas offset
    
    
    
    
    
    
    4,835Other
    
    
    5,839
    
    
    
    8,784Total current liabilities
    
    
    71,560
    
    
    
    68,930LONG-TERM DEBT
    
    
    693,437
    
    
    
    693,240DEFERRED CREDITS AND OTHER NONCURRENT LIABILITIES
    
    
    109,130
    
    
    
    106,095CONTINGENT LIABILITIES AND COMMITMENTSOWNERS EQUITY:Owners capital
    
    
    1,027,862
    
    
    
    978,682Loan to affiliate
    
    
    (105,431
    )
    
    
    (34,265
    )Retained earnings
    
    
    284,319
    
    
    
    265,668Accumulated other comprehensive income
    
    
    400
    
    
    
    462Total owners equity
    
    
    1,207,150
    
    
    
    1,210,547Total liabilities and owners equity
    
    $
    2,081,277
    
    
    $
    2,078,812
  45




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##### Table of Contents



NORTHWEST PIPELINE GP
 
 CONSOLIDATED STATEMENTS OF OWNERS EQUITY
  Years Ended December 31,2009
    
    
    2008
    
    
    2007(Restated)
    
    
    (Restated)Common stock, par value $1 per share,
authorized, 1,000 sharesBalance at beginning of period, outstanding,
1,000 shares for 2007
    
    $
    
    
    
    $
    
    
    
    $
    1Conversion to GP
    
    
    
    
    
    
    
    
    
    
    (1
    )Balance at end of period
    
    
    
    
    
    
    
    
    
    
    Additional paid-in capital -Balance at beginning of period
    
    
    
    
    
    
    
    
    
    
    977,021Conversion to GP
    
    
    
    
    
    
    
    
    
    
    (977,021
    )Balance at end of period
    
    
    
    
    
    
    
    
    
    
    Partners capital -Balance at beginning of period
    
    
    978,682
    
    
    
    977,022
    
    
    
    Capital contribution from partner
    
    
    49,180
    
    
    
    1,660
    
    
    
    Conversion to GP
    
    
    
    
    
    
    
    
    
    
    977,022Balance at end of period
    
    
    1,027,862
    
    
    
    978,682
    
    
    
    977,022Loans (to) from affiliate -Balance at beginning of period
    
    
    (34,265
    )
    
    
    (29,186
    )
    
    
    (29,364
    )Loans (to) from affiliate
    
    
    (71,166
    )
    
    
    (5,079
    )
    
    
    178Balance at end of period
    
    
    (105,431
    )
    
    
    (34,265
    )
    
    
    (29,186
    )Retained earnings (deficit) -Balance at beginning of period
    
    
    265,668
    
    
    
    228,739
    
    
    
    (101,214
    )Net income
    
    
    153,651
    
    
    
    155,371
    
    
    
    439,726Cash distributions
    
    
    (135,000
    )
    
    
    (419,342
    )
    
    
    (109,770
    )Sale of partnership interest
    
    
    
    
    
    
    300,900
    
    
    
    Other
    
    
    
    
    
    
    
    
    
    
    (3
    )Balance at end of period
    
    
    284,319
    
    
    
    265,668
    
    
    
    228,739Accumulated other comprehensive income (loss) Balance at beginning of period
    
    
    462
    
    
    
    523
    
    
    
    365Cash flow hedges:Reclassification of gain into earnings
    
    
    (62
    )
    
    
    (61
    )
    
    
    (62
    )Elimination of deferred income taxes
    
    
    
    
    
    
    
    
    
    
    220Balance at end of period
    
    
    400
    
    
    
    462
    
    
    
    523Total owners equity
    
    $
    1,207,150
    
    
    $
    1,210,547
    
    
    $
    1,177,098
  46




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##### Table of Contents



NORTHWEST PIPELINE GP
 
 CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
  Years Ended December 31,2009
    
    
    2008
    
    
    2007(Restated)
    
    



    (Restated)Net Income
    
    $
    153,651
    
    
    $
    155,371
    
    
    $
    439,726Cash Flow Hedges:Amortization of cash flow hedges
    
    
    (62
    )
    
    
    (61
    )
    
    
    (62
    )Elimination of deferred income taxes
    
    
    
    
    
    
    
    
    
    
    220Total comprehensive income
    
    $
    153,589
    
    
    $
    155,310
    
    
    $
    439,884
  47




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##### Table of Contents



NORTHWEST PIPELINE GP
 
 CONSOLIDATED STATEMENTS OF CASH FLOWS
 Years Ended December 31,2009
    
    
    2008
    
    
    2007(Restated)
    
    
    (Restated)OPERATING ACTIVITIES:Net Income
    
    $
    153,651
    
    
    $
    155,371
    
    
    $
    439,726Adjustments
to reconcile to net cash provided by operating activities -Depreciation
    
    
    86,373
    
    
    
    86,184
    
    
    
    84,731Regulatory credits
    
    
    (2,403
    )
    
    
    (2,617
    )
    
    
    (3,663
    )Gain on sale of property, plant and equipment
    
    
    (508
    )
    
    
    (378
    )
    
    
    Provision (benefit) for deferred income taxes
    
    
    
    
    
    
    
    
    
    
    (289,229
    )Amortization of deferred charges and credits
    
    
    12,561
    
    
    
    8,589
    
    
    
    9,783Allowance for equity funds used during construction
    
    
    (1,996
    )
    
    
    (812
    )
    
    
    (2,091
    )Reserve for doubtful accounts
    
    
    
    
    
    
    (7
    )
    
    
    (46
    )Regulatory liability reversal
    
    
    
    
    
    
    
    
    
    
    (16,562
    )Contract termination income
    
    
    
    
    
    
    
    
    
    
    (6,045
    )Cash
provided (used) by changes in current assets and liabilities:Trade accounts receivable
    
    
    (326
    )
    
    
    580
    
    
    
    (8,413
    )Affiliated receivables, including income taxes in 2007
    
    
    (3,284
    )
    
    
    2,284
    
    
    
    (2,923
    )Exchange gas due from others
    
    
    2,623
    
    
    
    4,583
    
    
    
    (1,654
    )Materials and supplies
    
    
    (143
    )
    
    
    527
    
    
    
    (331
    )Other current assets
    
    
    1,744
    
    
    
    943
    
    
    
    1,017Trade accounts payable
    
    
    (828
    )
    
    
    (2,599
    )
    
    
    4,653Affiliated payables, including income taxes in 2007
    
    
    275
    
    
    
    (6,572
    )
    
    
    (5,259
    )Exchange gas due to others
    
    
    (2,623
    )
    
    
    (4,583
    )
    
    
    1,654Other accrued liabilities
    
    
    (533
    )
    
    
    3,083
    
    
    
    2,105Changes in noncurrent assets and liabilities:Deferred charges
    
    
    (4,580
    )
    
    
    (423
    )
    
    
    (9,769
    )Other deferred credits
    
    
    (5,205
    )
    
    
    (5,139
    )
    
    
    7,673Net cash provided by operating activities
    
    
    234,798
    
    
    
    239,014
    
    
    
    205,357FINANCING ACTIVITIES:Proceeds from issuance of long-term debt
    
    
    
    
    
    
    249,333
    
    
    
    434,362Retirement of long-term debt
    
    
    
    
    
    
    (250,000
    )
    
    
    (252,867
    )Early retirement of long-term debt
    
    
    
    
    
    
    
    
    
    
    (175,000
    )Debt issuance costs
    
    
    
    
    
    
    (2,027
    )
    
    
    (2,059
    )Premium on early retirement of long-term debt
    
    
    
    
    
    
    
    
    
    
    (7,111
    )Capital contribution from parent
    
    
    49,180
    
    
    
    1,660
    
    
    
    Proceeds from sale of partnership interest
    
    
    
    
    
    
    300,900
    
    
    
    Distributions paid
    
    
    (135,000
    )
    
    
    (419,342
    )
    
    
    (109,770
    )Changes in cash overdrafts
    
    
    2,212
    
    
    
    (7,372
    )
    
    
    (30,078
    )Net cash used in financing activities
    
    
    (83,608
    )
    
    
    (126,848
    )
    
    
    (142,523
    )INVESTING ACTIVITIES:Property, plant and equipment -Capital expenditures*
    
    
    (152,580
    )
    
    
    (88,478
    )
    
    
    (156,761
    )Proceeds from sales
    
    
    2,234
    
    
    
    3,065
    
    
    
    2,257Proceeds from sale of Parachute facilities
    
    
    
    
    
    
    
    
    
    
    79,770Repayments from (advances to) affiliates
    
    
    (787
    )
    
    
    (26,905
    )
    
    
    10,908Net cash used in investing activities
    
    
    (151,133
    )
    
    
    (112,318
    )
    
    
    (63,826
    )NET INCREASE
(DECREASE) IN CASH AND CASH EQUIVALENTS
    
    
    57
    
    
    
    (152
    )
    
    
    (992
    )CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR
    
    
    345
    
    
    
    497
    
    
    
    1,489CASH AND CASH EQUIVALENTS AT END OF YEAR
    
    $
    402
    
    
    $
    345
    
    
    $
    497* Increases to property, plant and equipment
    
    $
    (156,576
    )
    
    $
    (78,566
    )
    
    $
    (157,163
    )Changes in related accounts payable and accrued liabilities
    
    
    3,996
    
    
    
    (9,912
    )
    
    
    402Capital expenditures
    
    $
    (152,580
    )
    
    $
    (88,478
    )
    
    $
    (156,761
    )Supplemental disclosures of non-cash transactions:Adjustment to owners equity for benefit plans correction
    
    $
    (4,402
    )
    
    $
    (5,079
    )
    
    $
    178Advances to affiliates reclassified to owners equity
    
    
    66,764
    
    
    
    
    
    
    
    
  48




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##### Table of Contents



NORTHWEST PIPELINE GP
 
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
 1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
 Corporate Structure and Control
       Nature of Operations
  Regulatory Accounting
  49




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##### Table of Contents



NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
   Basis of Presentation
  Use of Estimates
   Property, Plant and Equipment
    50




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##### Table of Contents



NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
    Allowance for Borrowed and Equity Funds Used During Construction
   Regulatory Allowance for Equity Funds Used During Construction
  Advances to Affiliates
   51




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##### Table of Contents



NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
  Accounts Receivable and Allowance for Doubtful Receivables
  Materials and Supplies Inventory
   Impairment of Long-Lived Assets
   Income Taxes
   Deferred Charges
  52




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##### Table of Contents



NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
 Cash and Cash Equivalents
  Revenue Recognition
    Environmental Matters
  Interest Payments
  Subsequent Events
  53




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##### Table of Contents



NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
 Accounting Standards Issued But Not Yet Adopted
   Change in Accounting Estimate
  2. RESTATEMENT
   54




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##### Table of Contents



NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
   December 31,2008Consolidated Balance Sheet:Deferred charges, as previously reported
    
    $
    22,213Correction to remove benefit plan assets
    
    
    3,360Deferred charges, as restated
    
    $
    18,853Total other assets, as previously reported
    
    $
    77,795Correction to remove benefit plan assets
    
    
    3,360Total other assets, as restated
    
    $
    74,435Total assets, as previously reported
    
    $
    2,082,172Correction to remove benefit plan assets
    
    
    3,360Total assets, as restated
    
    $
    2,078,812Accrued liabilities -Employee costs, as previously reported
    
    $
    10,505Correction to remove benefit plan liabilities
    
    
    79Employee costs, as restated
    
    $
    10,426Total current liabilities, as previously reported
    
    $
    69,009Correction to remove benefit plan liabilities
    
    
    79Total current liabilities as restated
    
    $
    68,930Deferred credits and other noncurrent liabilities, as previously reported
    
    $
    135,209Correction to remove benefit plan liabilities
    
    
    29,114Deferred credits and other noncurrent liabilities, as restated
    
    $
    106,095Loan to affiliate, as previously reported
    
    $
    Correction to remove benefit plan assets and liabilities
    
    
    34,265Loan to affiliate, as restated
    
    $
    (34,265
    )Accumulated other comprehensive loss, as previously reported
    
    $
    (59,636
    )Correction to remove benefit plans
    
    
    (60,098
    )Accumulated other comprehensive income, as restated
    
    $
    462Total owners equity, as previously reported
    
    $
    1,184,714Correction to remove benefit plan assets, liabilities, and other
comprehensive loss
    
    
    (25,833
    )Total owners equity, as restated
    
    $
    1,210,547Total liabilities and owners equity, as previously reported
    
    $
    2,082,172Correction to remove benefit plan assets, liabilities, and other
comprehensive loss
    
    
    3,360Total liabilities and owners equity, as restated
    
    $
    2,078,812
 55




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NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
 Years Ended December 31,2008
    
    
    2007Consolidated
Statements of Owners Equity:Loan to affiliate -Balance at beginning of period, as previously
reported
    
    $
    
    
    
    $
    Cumulative amount of benefit plans correction
    
    
    
    
    
    
    (29,364
    )Balance at beginning of period, as restated
    
    
    (29,186
    )
    
    
    (29,364
    )Loans (to) from affiliate
    
    
        (5,079
    )
    
    
    178Balance at end of period
    
    $
    (34,265
    )
    
    $
    (29,186
    )Accumulated other comprehensive income (loss) Balance at beginning of period, as previously
stated
    
    $
    
    
    
    $
    (17,863
    )Cumulative amount of benefit plans correction
    
    
    
    
    
    
    18,228Balance at beginning of period, as restated
    
    
    523
    
    
    
    365Cash flow hedges:Reclassification of gain into earnings
    
    
    (61
    )
    
    
    (62
    )Elimination of deferred income taxes
    
    
    
    
    
    
    220Balance at end of period
    
    $
    462
    
    
    $
    523
 Years Ended December 31,2008
    
    
    2007Consolidated Statements of Comprehensive Income:Total comprehensive income, as previously reported
    
    $
    115,880
    
    
    $
    437,444Correction to remove benefit plans
    
    
    (39,430
    )
    
    
    (2,440
    )Total comprehensive income, as restated
    
    $
    155,310
    
    
    $
    439,884
 3. RATE AND REGULATORY MATTERS
 Parachute Lateral Project
   56




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NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
  4. CONTINGENT LIABILITIES AND COMMITMENTS
 Legal Proceedings
  Environmental Matters
    Safety Matters
 Pipeline Integrity Regulations
 57




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##### Table of Contents



NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
  Other Matters
  Summary
  Other Commitments
  Cash Distributions to Partners
    5. DEBT, FINANCING ARRANGEMENTS AND LEASES
 Debt Covenants
  58




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##### Table of Contents



NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
 Long-Term Debt
   December 31,2009
    
    
    2008(Thousands of Dollars)5.95%, payable 2017
    
    $
    184,535
    
    
    $
    184,4716.05%, payable 2018
    
    
    249,440
    
    
    
    249,3747%, payable 2016
    
    
    174,643
    
    
    
    174,5877.125%, payable 2025
    
    
    84,819
    
    
    
    84,808Total long-term debt
    
    $
    693,437
    
    
    $
    693,240
  (Thousands of Dollars)2010
    
    $
    2011
    
    
    2012
    
    
    2013
    
    
    2014
    
    
    Thereafter
    
    
    695,000Total
    
    $
    695,000
 Line-of-Credit Arrangements
   59




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NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
 
    
    Williams ratio of debt to capitalization must be no greater than 65 percent. Williams
was in compliance with this covenant at December 31, 2009.
    
    Our ratio of debt to capitalization and that of another participating subsidiary of
Williams must be no greater than 55 percent. We were in compliance with this covenant at
December 31, 2009.
      Leases
   60




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##### Table of Contents



NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
    (Thousands of Dollars)2010
    
    $
    2,2842011
    
    
    2,2842012
    
    
    2,2842013
    
    
    2,2842014
    
    
    2,285Total
    
    $
    11,421
   6. EMPLOYEE BENEFIT PLANS
 Pension and other postretirement benefit plans
  Defined contribution plan
  61




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##### Table of Contents



NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
 Stock-Based Compensation
       7. INCOME TAXES
   Year Ended December 31,2009
    
    
    2008
    
    
    2007(Thousands of Dollars)Current:Federal
    
    $
    
    
    
    $
    
    
    
    $
    30,888State
    
    
    
    
    
    
    
    
    
    
    3,674
    
    
    
    
    
    
    
    34,562Deferred:Federal
    
    
    
    
    
    
    
    
    
    
    (258,459
    )State
    
    
    
    
    
    
    
    
    
    
    (30,770
    )
    
    
    
    
    
    
    
    (289,229
    )Total benefit
    
    $
    
    
    
    $
    
    
    
    $
    (254,667
    )
 62




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##### Table of Contents



NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
  Year
          Ended December 31,2009
        
        
        2008
        
        
        2007(Thousands of Dollars)Provision at statutory
            Federal income tax rate of 35 percent (1)
        
        $
        
        
        
        $
        
        
        
        $
        52,831Increase in tax provision
            resulting from -State income taxes
            net of Federal tax benefit
        
        
        
        
        
        
        
        
        
        
        3,948Book/tax basis reconciliation
            adjustment
        
        
        
        
        
        
        
        
        
        
        Other  net
        
        
        
        
        
        
        
        
        
        
        330Provision for income
            taxes prior to conversion from a corporation to a partnership
        
        $
        
        
        
        $
        
        
        
        $
        57,109Effective tax rate
            prior to conversion from a corporation to a partnership
        
        
        
        
        
        
        
        
        
        
        37.83
        %Provision for income
            taxes prior to conversion from a corporation to a partnership
        
        $
        
        
        
        $
        
        
        
        $
        57,109Conversion from corporation
            to partnership
        
        
        
        
        
        
        
        
        
        
        (311,776
        )Total benefit for income
            taxes
        
        $
        
        
        
        $
        
        
        
        $
        (254,667
        )
 
 (1)
    
    Following our conversion to a general partnership on October 1, 2007, we are no longer
subject to income tax. The provision for income taxes shown herein for 2007 reflects the
provision through September 30, 2007. Subsequent to the conversion to a general partnership
on October 1, 2007, all deferred income taxes were eliminated and we no longer provide for
income taxes.  8. FINANCIAL INSTRUMENTS
 Fair Value of Financial Instruments
  Cash, cash equivalents and advances to affiliate
 Long-term debt
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NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
 9. TRANSACTIONS WITH MAJOR CUSTOMERS AND AFFILIATES
 Concentration of Off-Balance-Sheet and Other Credit Risk
  Year Ended December 31,2009
    
    2008
    
    2007(Thousands of Dollars)Puget Sound Energy, Inc.
    
    $
    94,508
    
    
    $
    89,988
    
    
    $
    85,059Northwest Natural Gas Co.
    
    
    49,256
    
    
    
    (a)

    
    
    
    48,648
 
 (a)
    
    Under 10 percent in 2008  Related Party Transactions
    64




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##### Table of Contents



NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
   10. ASSET RETIREMENT OBLIGATIONS
   2009
    
    
    2008Beginning balance
    
    $
    82,666
    
    
    $
    50,423Accretion
    
    
    6,068
    
    
    
    4,341New obligations
    
    
    2,594
    
    
    
    116Changes in estimates of existing obligations
    
    
    (4,579
    )
    
    
    27,790Obligation settled
    
    
    
    
    
    
    (4
    )Ending Balance
    
    $
    86,749
    
    
    $
    82,666
  11. REGULATORY ASSETS AND LIABILITIES
  65




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NORTHWEST PIPELINE GP
 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
 2009
    
    
    2008(Restated)(Thousands of Dollars)Current regulatory assets  environmental costs
    
    $
    2,200
    
    
    $
    2,200Noncurrent regulatory assetsEnvironmental costs
    
    
    3,590
    
    
    
    5,790Grossed-up deferred taxes on equity funds used during construction
    
    
    18,346
    
    
    
    19,234Levelized incremental depreciation
    
    
    30,801
    
    
    
    28,397Asset retirement obligations, net
    
    
    4,295
    
    
    
    1,189Other post-employment benefits
    
    
    
    
    
    
    972Total noncurrent regulatory assets
    
    
    57,032
    
    
    
    55,582Total regulatory assets
    
    $
    59,232
    
    
    $
    57,782Noncurrent regulatory liabilitiesPostretirement benefits
    
    $
    15,134
    
    
    $
    14,652Total regulatory liabilities
    
    $
    15,134
    
    
    $
    14,652
 12. QUARTERLY INFORMATION (UNAUDITED)
  Quarter of 2009First
    
    Second
    
    Third
    
    Fourth(Thousands of Dollars)Operating revenues
    
    $
    111,548
    
    
    $
    107,756
    
    
    $
    106,615
    
    
    $
    108,460Operating income
    
    
    53,152
    
    
    
    47,013
    
    
    
    49,145
    
    
    
    51,199Net income
    
    
    40,908
    
    
    
    35,162
    
    
    
    38,260
    
    
    
    39,321
 Quarter of 2008First
    
    Second
    
    Third
    
    Fourth(Thousands of Dollars)Operating revenues
    
    $
    107,405
    
    
    $
    106,450
    
    
    $
    108,542
    
    
    $
    112,457Operating income
    
    
    49,166
    
    
    
    46,676
    
    
    
    53,042
    
    
    
    52,294Net income
    
    
    38,158
    
    
    
    35,685
    
    
    
    41,236
    
    
    
    40,292
  66




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Item 9.
    
    CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE
  
 ITEM 9A(T).
    
    Controls and Procedures
 Disclosure Controls and Procedures
    Managements Annual Report on Internal Control over Financial Reporting
  Changes in Internal Controls Over Financial Reporting
  67




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Item 9B.
    
    OTHER INFORMATION
  68




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PART III
 
 Item 10.
    
    DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE
 Management Committee Member and Executive Officers
   Name
    
    Age
    
    PositionPhillip D. Wright
    
    
    54
    
    
    Senior Vice President and
Management Committee Member
(Principal Executive Officer)Donald R. Chappel
    
    
    58
    
    
    Management Committee MemberSteven J. Malcolm
    
    
    61
    
    
    Chief Executive OfficerRichard D. Rodekohr
    
    
    51
    
    
    Vice President and Treasurer
(Principal Financial Officer)Allison G. Bridges
    
    
    50
    
    
    Vice PresidentRandall L. Barnard
    
    
    51
    
    
    Vice PresidentLawrence G. Hjalmarson
    
    
    55
    
    
    Vice PresidentRandall R. Conklin
    
    
    53
    
    
    Vice President and General CounselFrank J. Ferazzi
    
    
    53
    
    
    Vice President
      69




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##### Table of Contents



Section 16(a) Beneficial Ownership Reporting Compliance
  Code of Ethics
  Corporate Governance
  
 Item 11.
    
    EXECUTIVE COMPENSATION
 Compensation Discussion and Analysis
 http://www.sec.gov http://www.williams.com
 70




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##### Table of Contents



Executive Compensation
  2009 Summary Compensation Table
 Change inPension ValueandNonqualifiedNon-Equity
    
    DeferredStock
    
    Option
    
    Incentive Plan
    
    Compensation
    
    All OtherName
    
    Year
    
    Salary
    
    Bonus
    
    Awards
    
    Awards
    
    Compensation
    
    Earnings
    
    Compensation
    
    TotalPhillip D. Wright
    
    
    2009
    
    
    $
    111,204
    
    
    $
    
    
    
    $
    96,651
    
    
    $
    148,250
    
    
    $
    120,287
    
    
    $
    89,934
    
    
    $
    4,607
    
    
    $
    570,933Senior Vice President
    
    
    2008
    
    
    
    130,579
    
    
    
    
    
    
    
    (21,196
    )
    
    
    84,665
    
    
    
    146,250
    
    
    
    100,148
    
    
    
    2,626
    
    
    
    443,072(Principal Executive Officer)
    
    
    2007
    
    
    
    92,681
    
    
    
    
    
    
    
    408,204
    
    
    
    66,898
    
    
    
    129,929
    
    
    
    13,203
    
    
    
    1,902
    
    
    
    712,817Richard D,
Rodekohr
    
    
    2009
    
    
    
    48,225
    
    
    
    
    
    
    
    17,480
    
    
    
    22,518
    
    
    
    33,606
    
    
    
    36,789
    
    
    
    3,109
    
    
    
    161,727Vice President and Treasurer
    
    
    2008
    
    
    
    53,474
    
    
    
    
    
    
    
    14,028
    
    
    
    21,662
    
    
    
    35,696
    
    
    
    40,088
    
    
    
    3,396
    
    
    
    168,344(Principal Financial Officer)
    
    
    2007
    
    
    
    44,358
    
    
    
    
    
    
    
    100,495
    
    
    
    22,953
    
    
    
    36,913
    
    
    
    (121
    )
    
    
    2,966
    
    
    
    207,564Allison G. Bridges
    
    
    2009
    
    
    
    259,615
    
    
    
    
    
    
    
    73,173
    
    
    
    96,301
    
    
    
    202,488
    
    
    
    188,741
    
    
    
    15,105
    
    
    
    835,423Vice President
    
    
    2008
    
    
    
    248,500
    
    
    
    
    
    
    
    12,850
    
    
    
    94,020
    
    
    
    196,013
    
    
    
    217,251
    
    
    
    11,905
    
    
    
    780,5392007
    
    
    
    235,211
    
    
    
    
    
    
    
    421,027
    
    
    
    95,960
    
    
    
    196,919
    
    
    
    1,832
    
    
    
    13,895
    
    
    
    964,844Randall L. Barnard
    
    
    2009
    
    
    
    21,527
    
    
    
    
    
    
    
    6,473
    
    
    
    8,366
    
    
    
    19,277
    
    
    
    16,355
    
    
    
    1,044
    
    
    
    73,042Vice President
    
    
    2008
    
    
    
    32,038
    
    
    
    
    
    
    
    1,318
    
    
    
    12,783
    
    
    
    28,739
    
    
    
    23,379
    
    
    
    1,529
    
    
    
    99,7862007
    
    
    
    72,584
    
    
    
    
    
    
    
    142,715
    
    
    
    33,037
    
    
    
    76,975
    
    
    
    3,091
    
    
    
    3,644
    
    
    
    332,046Lawrence G. Hjalmarson
    
    
    2009
    
    
    
    8,964
    
    
    
    
    
    
    
    3,202
    
    
    
    4,444
    
    
    
    6,079
    
    
    
    6,370
    
    
    
    618
    
    
    
    29,677Vice President
    
    
    2008
    
    
    
    10,823
    
    
    
    
    
    
    
    2,563
    
    
    
    5,729
    
    
    
    7,098
    
    
    
    6,573
    
    
    
    606
    
    
    
    33,3922007
    
    
    
    68,301
    
    
    
    
    
    
    
    16,427
    
    
    
    22,957
    
    
    
    51,332
    
    
    
    1,345
    
    
    
    5,009
    
    
    
    165,371
 Compensation Committee Interlocks and Insider Participation
  Compensation of Directors
  Compensation Committee Report
  
 71




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Item 12.
    
    SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS
  
 Item 13.
    
    CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE
     
    
    the liquidation, dissolution or winding up of Northwest or making any bankruptcy
filing;
    
    the issuance, incurrence, assumption or guarantee of any indebtedness or the
pledge of any of Northwests assets;
    
    filing or resolving a Section 4 general rate case proceeding under the Natural
Gas Act or any other proceeding or controversy at FERC or an appeal of a FERC
order, the outcome of which would cause (A) Northwest to have reduced revenue of,
or pay penalties, refunds or interest in excess of, $50 million, or (B) Northwest
to agree to any criminal penalty;
    
    any amendment of the Northwest partnership agreement;
    
    any distributions to Northwests partners, other than the distributions of
available cash to be made at least quarterly as described below;
    
    the admission of any person as a partner (other than a permitted transferee of a
partner) or the issuance of any partnership interests or other equity interests of
Northwest or any withdrawal by any partner from Northwest;
    
    the transfer, redemption, repurchase or other acquisition of interests in
Northwest;
    
    the disposition of substantially all of the assets of Northwest or any portion
of such assets with a value exceeding $20 million;
    
    any merger or consolidation of Northwest with another person or any conversion
or reorganization of Northwest;
    
    entering into any activity or business that may generate income that may not be
qualifying income under Section 7704 of the Internal Revenue Code;
    
    the approval of Northwests budget;
    
    the approval of a transfer by a partner of its interest in Northwest; and
 72




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##### Table of Contents




    
    any amendment to the administrative services agreement to which Northwest is a
party.
 Quarterly Cash Distributions
 plus less
 Capital Calls to the Partners
  Restrictions on Transfer of Interests in Northwest
  Profit and Loss Allocations
  Agreement with Regard to Colorado Hub Connection Project
  Williams Cash Management Program
  73




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##### Table of Contents



Other Related Party Transactions
      
 Item 14. PRINCIPAL ACCOUNTING FEES AND SERVICES
  2009
    
    
    2008(Thousands of Dollars)Audit Fees
    
    $
    862
    
    
    $
    1,038Audit-Related Fees
    
    
    
    
    
    
    Tax Fees
    
    
    
    
    
    
    All Other Fees
    
    
    
    
    
    
    $
    862
    
    
    $
    1,038
   74




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##### Table of Contents



http://www.sec.gov http://williams.com
 75




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PART IV
 
 Item 15. EXHIBITS, FINANCIAL STATEMENT SCHEDULES
 (a) 1. Financial Statements
 Index
 Page Reference to2009 Form 10-KManagements Annual Report on Internal Control over Financial Reporting
    
    
    41Report of Independent Registered Public Accounting Firm
    
    
    42Consolidated Statements of Income for the Years Ended December 31, 2009, 2008
    
    
    43and 2007Consolidated Balance Sheets at December 31, 2009 and 2008
    
    
    44Consolidated Statements of Owners Equity for the Years Ended December 31, 2009,
    
    
    462008 and 2007Consolidated Statements of Comprehensive Income for the Years Ended December
    
    
    4731, 2009, 2008 and 2007Consolidated Statements of Cash Flows for the Years Ended December 31, 2009,
    
    
    482008 and 2007Notes to Consolidated Financial Statements
    
    
    49
 76




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##### Table of Contents



(a) 2. Financial Statement Schedules
 
 Charged toBeginning
    
    
    Costs and
    
    
    
    
    
    
    EndingDescription
    
    Balance
    
    
    Expenses
    
    
    Deductions
    
    
    BalancesYear ended December 31, 2009:Reserve for doubtful receivables
    
    $
    
    
    
    $
    
    
    
    $
    
    
    
    $
    Reserve for obsolescence of
materials and supplies
    
    
    111
    
    
    
    145
    
    
    
    (245
    )
    
    
    11Year ended December 31, 2008:Reserve for doubtful receivables
    
    
    7
    
    
    
    (7
    )
    
    
    
    
    
    
    Reserve for obsolescence of
materials and supplies
    
    
    181
    
    
    
    141
    
    
    
    (211
    )
    
    
    111Year ended December 31, 2007:Reserve for doubtful receivables
    
    
    53
    
    
    
    (46
    )
    
    
    
    
    
    
    7Reserve for obsolescence of
materials and supplies
    
    
    472
    
    
    
    104
    
    
    
    (395
    )
    
    
    181
  (a) 3 and b. Exhibits:
 (2)
    
    Plan of acquisition, reorganization, arrangement, liquidation or succession:
 (a)
    
    Certificate of Conversion of Northwest Pipeline Corporation (Exhibit 2.1 to
Northwest report on Form 8-K, No. 1-7414, filed
October 2, 2007) and incorporated herein by reference.
 (3)
    
    Articles of incorporation and by-laws:
 (a)
    
    Statement of Partnership Existence of Northwest Pipeline GP (Exhibit 3.1 to
Northwest report on Form 8-K, No. 1-7414, filed October 2, 2007) and incorporated herein by reference.(b)
    
    Amended and Restated General Partnership Agreement of Northwest Pipeline GP
(Exhibit 3.1 to Northwest report on Form 8-K, No. 1-7414, filed January 30, 2008) and incorporated herein by reference.
 (4)
    
    Instruments defining the rights of security holders, including indentures:
 (a)
    
    Senior Indenture, dated as of November 30, 1995 between Northwest and Chemical
Bank, relating to Pipelines 7.125% Debentures, due 2025 (Exhibit 4.1 to Registration
Statement on Form S-3, No. 33-62639, filed September 14, 1995) and incorporated herein by reference.(b)
    
    Indenture, dated as of June 22, 2006, between Northwest Pipeline Corporation and
JPMorgan Chase Bank, N.A. (Exhibit 4.1 to Northwest report on Form 8-K, No. 1-7414,
filed June 23, 2006) and incorporated herein by reference.
 77




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##### Table of Contents



(c)
    
    Indenture, dated as of April 5, 2007, between Northwest Pipeline Corporation and
The Bank of New York (Exhibit 4.1 to Northwest report on Form 8-K, No. 1-7414, filed
April 6, 2007) and incorporated herein by reference.(d)
    
    Indenture, dated May 22, 2008, between Northwest Pipeline GP and The Bank of New
York Trust Company, N.A., as Trustee (filed as exhibit 4.1 to Northwest Pipeline GPs
Form 8-K, filed May 23, 2008) and incorporated herein by reference.
 (10)
    
    Material contracts:
 (a)
    
    Credit Agreement, dated as of May 1, 2006, among The Williams Companies, Inc.,
Northwest Pipeline Corporation, Transcontinental Gas Pipe Line Corporation, and Williams
Partners L.P., as Borrowers, and Citibank, N.A., as Administrative Agent (Exhibit 10.1
to The Williams Companies, Inc. Form 8-K filed May 1, 2006 Commission File Number
1-4174) and incorporated herein by reference.(b)
    
    Amendment Agreement, dated May 9, 2007, among The Williams Companies, Inc.,
Williams Partners L.P., Northwest Pipeline Corporation, Transcontinental Gas Pipe Line
Corporation, certain banks, financial institutions and other institutional lenders and
Citibank, N.A., as administrative agent (Exhibit 10.1 to The Williams Companies, Inc.
report on Form 8-K filed May 15, 2007, Commission File Number 1-4174) and incorporated herein by reference.(c)
    
    Amendment Agreement dated November 21, 2007, among The Williams Companies, Inc.,
Williams Partners L.P., Northwest Pipeline GP, Transcontinental Gas Pipe Line
Corporation, certain banks, financial institutions and other institutional lenders and
Citibank, N.A., as administrative agent (Exhibit 10.1 to the Williams Companies, Inc.,
Form 8-K, filed November 28, 2007, Commission File Number 1-4174) and incorporated herein by reference.(d)
    
    Administrative Services Agreement, dated January 24, 2008, between Northwest
Pipeline GP and Northwest Pipeline Services, LLC (Exhibit 10.1 to Northwest report on
Form 8-K, No. 1-7414, filed January 30, 2008) and incorporated herein by reference.(e)
    
    Contribution, Conveyance and Assumption Agreement, dated January 24, 2008, among
Williams Pipeline Partners L.P., Williams Pipeline Operating LLC, WPP Merger LLC,
Williams Pipeline Partners Holdings LLC, Northwest Pipeline GP, Williams Pipeline GP
LLC, Williams Gas Pipeline Company, LLC, WGPC Holdings LLC and Williams Pipeline
Services Company (Exhibit 10.2 to Northwest report on Form 8-K, No. 1-7414, filed
January 30, 2008) and incorporated herein by reference.(f)
    
    Registration Rights Agreement, dated as of May 22, 2008, among Northwest Pipeline
GP and Banc of America Securities LLC, BNP Paribas Securities Corp., and Greenwich
Capital Markets, Inc., acting on behalf of themselves and the several initial purchasers
listed on Schedule I thereto (filed as Exhibit 10.1 to our Form 8-K, dated May 23,
2008) and incorporated herein by reference.(g)
    
    Credit Agreement, dated as of February 17, 2010, by and
among Williams Partners L.P., Transcontinental Gas Pipe Line
Company, LLC, Northwest Pipeline GP, the lenders party thereto and
Citibank, N.A., as Administrative Agent (filed as Exhibit 10.5 to
Williams Partners L.P.s Current Report on Form 8-K, filed on
February 22, 2010 (File No. 001-32599) and incorporated by
reference as Item 10.1 to our Form 8-K, filed February 22, 2010)
and incorporated herein by reference.
 (12)*
    
    Computation of Ratio of Earnings to Fixed Charges
 (23)*
    
    Consent of Independent Registered Public Accounting Firm(24)*
    
    Power of Attorney(31)
    
    Section  302 Certifications
 78




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##### Table of Contents



(a)*
    
    Certification of Principal Executive Officer pursuant to Rules 13a-14(a) and
15d-14(a) promulgated under the Securities Exchange Act of 1934, as amended and Item
601(b)(31) of Regulation S-K, as adopted pursuant to Section 302 of The Sarbanes-Oxley
Act of 2002.(b)*
    
    Certification of Principal Financial Officer pursuant to Rules 13a-14(a) and
15d-14(a) promulgated under the Securities Exchange Act of 1934, as amended, and Item
601(b)(31) of Regulation S-K, as adopted pursuant to Section 302 of The Sarbanes-Oxley
Act of 2002.
 (32)
    
    Section 906 Certification
 (a)*
    
    Certification of Principal Executive Officer and Principal Financial Officer
pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002.
 
 *
    
    Filed herewith 79




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##### Table of Contents



SIGNATURES
  NORTHWEST PIPELINE GP
(Registrant)By
    /s/ R. Rand ClarkR. Rand ClarkController   Signature
    
    Title/s/ Phillip D. Wright*
    
    Senior Vice President and Management Committee MemberPhillip D. Wright
    
    (Principal Executive Officer)/s/ Richard D. Rodekohr

Richard D. Rodekohr
    
    Vice President and Treasurer 

(Principal Financial Officer)/s/ Allison G. Bridges

Allison G. Bridges
    
    Vice President/s/ R. Rand Clark
    
    Controller (Principal Accounting Officer)R. Rand Clark/s/ Steven J. Malcolm*
    
    Chief Executive OfficerSteven J. Malcolm/s/ Donald R. Chappel*
    
    Management Committee MemberDonald R. Chappel* By /s/ R. Rand Clark

R. Rand ClarkAttorney-in-fact
  80




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##### Table of Contents



Exhibit
    
    Description2
    (a)
    
    Certificate of Conversion of Northwest Pipeline Corporation (Exhibit 2.1 to Northwest
report on Form 8-K, No. 1-7414, filed October 2, 2007) and incorporated herein by reference.3
    (a)
    
    Statement of Partnership Existence of Northwest Pipeline GP (Exhibit 3.1 to Northwest
report on Form 8-K, No. 1-7414, filed October 2, 2007) and incorporated herein by reference.3
    (b)
    
    Amended and Restated General Partnership Agreement of Northwest Pipeline GP (Exhibit 3.1
to Northwest report on Form 8-K, No. 1-7414, filed January 30, 2008) and incorporated herein by reference.4
    (a)
    
    Senior Indenture, dated as of November 30, 1995 between Northwest and Chemical Bank,
relating to Pipelines 7.125% Debentures, due 2025 (Exhibit 4.1 to Registration Statement on
Form S-3, No. 33-62639, filed September 14, 1995) and incorporated herein by reference.4
    (b)
    
    Indenture, dated as of June 22, 2006, between Northwest Pipeline Corporation and JPMorgan
Chase Bank, N.A. (Exhibit 4.1 to Northwest report on Form 8-K, No. 1-7414, filed June 23,
2006) and incorporated herein by reference.4
    (c)
    
    Indenture, dated as of April 5, 2007, between Northwest Pipeline Corporation and The Bank
of New York (Exhibit 4.1 to Northwest report on Form 8-K, No. 1-7414, filed April 6, 2007) and incorporated herein by reference.4
    (d)
    
    Indenture, dated May 22, 2008, between Northwest Pipeline GP and The Bank of New York
Trust Company, N.A., as Trustee (filed as exhibit 4.1 to Northwest Pipeline GPs Form 8-K,
filed May 23, 2008) and incorporated herein by reference.10
    (a)
    
    Credit Agreement, dated as of May 1, 2006, among The Williams Companies, Inc., Northwest
Pipeline Corporation, Transcontinental Gas Pipe Line Corporation, and Williams Partners L.P.,
as Borrowers, and Citibank, N.A., as Administrative Agent (Exhibit 10.1 to The Williams
Companies, Inc. Form 8-K filed May 1, 2006 Commission File Number 1-4174) and incorporated herein by reference.10
    (b)
    
    Amendment Agreement, dated May 9, 2007, among The Williams Companies, Inc., Williams
Partners L.P., Northwest Pipeline Corporation, Transcontinental Gas Pipe Line Corporation,
certain banks, financial institutions and other institutional lenders and Citibank, N.A., as
administrative agent (Exhibit 10.1 to The Williams Companies, Inc. report on Form 8-K filed
May 15, 2007, Commission File Number 1-4174) and incorporated herein by reference.10
    (c)
    
    Amendment Agreement dated November 21, 2007, among The Williams Companies, Inc., Williams
Partners L.P., Northwest Pipeline GP, Transcontinental Gas Pipe Line Corporation, certain
banks, financial institutions and other institutional lenders and Citibank, N.A., as
administrative agent (Exhibit 10.1 to the Williams Companies, Inc., Form 8-K, filed November
28, 2007, Commission File Number 1-4174) and incorporated herein by reference.10
    (d)
    
    Administrative Services Agreement, dated January 24, 2008, between Northwest Pipeline GP
and Northwest Pipeline Services, LLC (Exhibit 10.1 to Northwest report on Form 8-K, No.
1-7414, filed January 30, 2008) and incorporated herein by reference.10
    (e)
    
    Contribution, Conveyance and Assumption Agreement, dated January 24, 2008, among Williams
Pipeline Partners L.P., Williams Pipeline Operating LLC, WPP Merger LLC, Williams Pipeline
Partners Holdings LLC, Northwest Pipeline GP, Williams Pipeline GP LLC, Williams Gas Pipeline
Company, LLC, WGPC Holdings LLC and Williams Pipeline Services Company (Exhibit 10.2 to
Northwest report on Form 8-K, No. 1-7414, filed January 30, 2008) and incorporated herein by reference.
 81




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##### Table of Contents



Exhibit
    
    Description10(f)
    
    
    Registration Rights Agreement, dated as of May 22, 2008, among Northwest Pipeline GP and
Banc of America Securities LLC, BNP Paribas Securities Corp., and Greenwich Capital Markets,
Inc., acting on behalf of themselves and the several initial purchasers listed on Schedule I
thereto (filed as Exhibit 10.1 to our Form 8-K, dated May 23, 2008) and incorporated herein by reference.10(g)
    
    

Credit Agreement, dated as of February 17, 2010, by and among Williams Partners L.P., Transcontinental Gas Pipe Line Company, LLC, Northwest Pipeline GP, the lenders party
thereto and Citibank, N.A., as Administrative Agent (filed as Exhibit
10.5 to Williams Partners L.P.s Current
 Report on Form 8-K, filed on February 22, 2010 (File No. 001-32599) and incorporated by reference as Item 10.1 to our Form 8-K, filed February 22, 2010) and incorporated herein by reference.12*
    
    
    Computation of Ratio of Earnings to Fixed Charges23*
    
    
    Consent of Independent Registered Public Accounting Firm24*
    
    
    Power of Attorney31(a)*
    
    
    Certification of Principal Executive Officer pursuant to Rules 13a-14(a) and 15d-14(a)
promulgated under the Securities Exchange Act of 1934, as amended and Item 601(b)(31) of
Regulation S-K, as adopted pursuant to Section 302 of The Sarbanes-Oxley Act of 2002.31(b)*
    
    
    Certification of Principal Financial Officer pursuant to Rules 13a-14(a) and 15d-14(a)
promulgated under the Securities Exchange Act of 1934, as amended, and Item 601(b)(31) of
Regulation S-K, as adopted pursuant to Section 302 of The Sarbanes-Oxley Act of 2002.32(a)*
    
    
    Certification of Principal Executive Officer and Principal Financial Officer pursuant to 18
U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
 
 *
    
    Filed herewith 82