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UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
Form 10-K
(Mark One)
ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the fiscal year ended December 31, 2020
OR
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 1-4174
The Williams Companies, Inc.
(Exact Name of Registrant as Specified in Its Charter)
Delaware 73-0569878
(State or Other Jurisdiction of
Incorporation or Organization)
 (IRS Employer
Identification No.)
One Williams Center
TulsaOklahoma 74172
(Address of Principal Executive Offices) (Zip Code)
918-573-2000
(Registrant’s Telephone Number, Including Area Code)
Securities registered pursuant to Section 12(b) of the Act:
Title of Each ClassTrading Symbol(s)Name of Each Exchange on Which Registered
Common Stock, $1.00 par valueWMBNew York Stock Exchange
Securities registered pursuant to Section 12(g) of the Act:
None
Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes     No  
Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    Yes      No  
Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes      No  
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).    Yes      No  
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
Large accelerated filerAccelerated filerNon-accelerated filerSmaller reporting companyEmerging growth company
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.
Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).    Yes      No  
The aggregate market value of the voting and non-voting common equity held by non-affiliates computed by reference to the price at which the common equity was last sold as of the last business day of the registrant’s most recently completed second quarter was approximately $23,078,419,375.
The number of shares outstanding of the registrant’s common stock outstanding at February 19, 2021 was 1,213,790,391.
DOCUMENTS INCORPORATED BY REFERENCE
Portions of the Registrant’s Definitive Proxy Statement for the Registrant’s Annual Meeting of Stockholders to be held on April 27, 2021, are incorporated into Part III, as specifically set forth in Part III.



THE WILLIAMS COMPANIES, INC.
FORM 10-K

TABLE OF CONTENTS
 Page
PART I
Item 1.
Item 1A.
Item 1B.
Item 2.
Item 3.
Item 4.
PART II
Item 5.
Item 7.
Item 7A.
Item 8.
Item 9.
Item 9A.
Item 9B.
PART III
Item 10.
Item 11.
Item 12.
Item 13.
Item 14.
PART IV
Item 15.
Item 16.

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DEFINITIONS
The following is a listing of certain abbreviations, acronyms, and other industry terminology that may be used throughout this Annual Report.
Measurements:
Barrel: One barrel of petroleum products that equals 42 U.S. gallons
Mbbls/d: One thousand barrels per day
Bcf : One billion cubic feet of natural gas
Bcf/d: One billion cubic feet of natural gas per day
MMcf/d: One million cubic feet per day
British Thermal Unit (Btu): A unit of energy needed to raise the temperature of one pound of water by one degree Fahrenheit
Tbtu: One trillion British thermal units
Dekatherms (Dth): A unit of energy equal to one million British thermal units
Mdth/d: One thousand dekatherms per day
MMdth: One million dekatherms or approximately one trillion British thermal units
MMdth/d: One million dekatherms per day
Consolidated Entities:
Caiman II: Caiman Energy II, LLC, (renamed Blue Racer Midstream Holdings, LLC, effective February 2, 2021) a former equity-method investment which is a consolidated entity following our November 2020 acquisition of an additional ownership interest
Cardinal: Cardinal Gas Services, L.L.C.
Gulfstar One: Gulfstar One LLC
Northwest Pipeline: Northwest Pipeline LLC
Transco: Transcontinental Gas Pipe Line Company, LLC
UEOM: Utica East Ohio Midstream LLC, previously a Partially Owned Entity until acquiring remaining interest in March 2019
Northeast JV: Ohio Valley Midstream LLC, a partially owned venture that includes our Ohio Valley assets and UEOM
WPZ: Williams Partners L.P. Effective August 10, 2018, we completed our merger with WPZ, pursuant to which we acquired all outstanding common units of WPZ held by others and Williams continued as the surviving entity.
Partially Owned Entities: Entities in which we do not own a 100 percent ownership interest and which, as of December 31, 2020, we account for as equity-method investments, including principally the following:
Aux Sable: Aux Sable Liquid Products LP
Blue Racer: Blue Racer Midstream LLC
Constitution: Constitution Pipeline Company, LLC
Discovery: Discovery Producer Services LLC
Gulfstream: Gulfstream Natural Gas System, L.L.C.
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Jackalope: Jackalope Gas Gathering Services, L.L.C., which was sold in April 2019
Laurel Mountain: Laurel Mountain Midstream, LLC
OPPL: Overland Pass Pipeline Company LLC
RMM: Rocky Mountain Midstream Holdings LLC
Targa Train 7: Targa Train 7 LLC
Government and Regulatory:
EPA: Environmental Protection Agency
Exchange Act, the: Securities and Exchange Act of 1934, as amended
FERC: Federal Energy Regulatory Commission
IRS: Internal Revenue Service
SEC: Securities and Exchange Commission
Other:
EBITDA: Earnings before interest, taxes, depreciation, and amortization
Fractionation: The process by which a mixed stream of natural gas liquids is separated into constituent products, such as ethane, propane, and butane
GAAP: U.S. generally accepted accounting principles
LNG: Liquefied natural gas; natural gas which has been liquefied at cryogenic temperatures
MVC: Minimum volume commitments
NGLs: Natural gas liquids; natural gas liquids result from natural gas processing and crude oil refining and are used as petrochemical feedstocks, heating fuels, and gasoline additives, among other applications
NGL margins: NGL revenues less Btu replacement cost, plant fuel, transportation, and fractionation
WPZ Merger: The August 10, 2018, merger transactions pursuant to which we acquired all outstanding common units of WPZ held by others, merged WPZ into Williams, and Williams continued as the surviving entity.

The statements in this Annual Report that are not historical information, including statements concerning plans and objectives of management for future operations, economic performance or related assumptions, are forward-looking statements. Forward-looking statements may be identified by various forms of words such as “anticipates,” “believes,” “seeks,” “could,” “may,” “should,” “continues,” “estimates,” “expects,” “forecasts,” “intends,” “might,” “goals,” “objectives,” “targets,” “planned,” “potential,” “projects,” “scheduled,” “will,” “assumes,” “guidance,” “outlook,” “in-service date,” or other similar expressions and other words and terms of similar meaning. Although we believe that our expectations regarding future events are based on reasonable assumptions, we can give no assurance that such expectations or assumptions will be achieved. Additional information regarding forward-looking statements and important factors that could cause actual results to differ materially from those in the forward-looking statements are described under Part I, Item 1A in this Annual Report.


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PART I

Item 1. Business
In this report, Williams (which includes The Williams Companies, Inc. and, unless the context otherwise indicates, all of our subsidiaries) is at times referred to in the first person as “we,” “us,” or “our.” We also sometimes refer to Williams as the “Company.”
GENERAL
We are an energy infrastructure company committed to be the leader in providing infrastructure that safely delivers natural gas products to reliably fuel the clean energy economy. We have operations in 15 supply areas that provide natural gas gathering, processing, and transmission services and natural gas liquids fractionation, transportation, and storage services to more than 600 customers. We own an interest in and operate over 30,000 miles of pipelines, 34 processing facilities, 9 fractionation facilities, and approximately 23 million barrels of NGL storage capacity, handling approximately 30 percent of the nation’s natural gas volumes.
wmb-20201231_g1.jpg
We were founded in 1908, originally incorporated under the laws of the state of Nevada in 1949 and reincorporated under the laws of the state of Delaware in 1987. Our common stock trades on the New York Stock Exchange under the symbol “WMB.” Our operations are located in the United States. Williams’ headquarters are located in Tulsa, Oklahoma, with other major offices in Salt Lake City, Utah; Houston, Texas; and Pittsburgh, Pennsylvania. Our telephone number is 918-573-2000.


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wmb-20201231_g2.jpg
Service Assets, Customers, and Contracts
Interstate Natural Gas Pipeline Assets
Our interstate natural gas pipelines, which are presented in our Transmission & Gulf of Mexico segment as described under the heading “Business Segments,” are subject to regulation by the FERC and as such, our rates and charges for the transportation of natural gas in interstate commerce are subject to regulation. The rates are established through the FERC’s ratemaking process.
Our interstate natural gas pipelines transport and store natural gas for a broad mix of customers, including local natural gas distribution companies, public utilities, municipalities, direct industrial users, electric power generators, and natural gas marketers and producers. Our interstate natural gas transmission businesses are fully contracted under long-term firm reservation contracts with high credit quality customers. These contracts have various expiration dates and account for the major portion of our regulated businesses, and are not exposed to crude oil prices. Additionally, we offer storage services and interruptible transportation services under shorter-term agreements. Transco’s and Northwest Pipeline’s three largest customers in 2020 accounted for approximately 28 percent and 51 percent, respectively, of their total operating revenues.
Gathering, Processing, and Treating Assets
Our gathering, processing, and treating operations are presented within our Transmission & Gulf of Mexico, Northeast G&P, and West reporting segments as described under the heading “Business Segments.”
Our gathering systems receive natural gas from producers’ crude oil and natural gas wells and gather these volumes to gas processing, treating, or redelivery facilities. Typically, natural gas, in its raw form, is not acceptable for transportation in major interstate natural gas pipelines or for commercial use as a fuel. Our treating facilities
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remove water vapor, carbon dioxide, and other contaminants, and collect condensate. We are generally paid a fee based on the volume of natural gas gathered and/or treated, generally measured in the Btu heating value.

In addition, natural gas contains various amounts of NGLs, which generally have a higher value when separated from the natural gas stream. Our processing plants extract the NGLs, which include ethane, primarily used in the petrochemical industry; propane, used for heating, fuel, and also in the petrochemical industry; and, normal butane, isobutane, and natural gasoline, primarily used by the refining industry.
Our gas processing services generate revenues primarily from the following types of contracts:
Fee-based: We are paid a fee based on the volume of natural gas processed, generally measured in the Btu heating value. A portion of our fee-based processing revenue includes a share of the margins on the NGLs produced. For the year ended December 31, 2020, approximately 80 percent of our NGL production volumes were under fee-based contracts.
Noncash commodity-based: We also process gas under two types of commodity-based contracts, keep-whole and percent-of-liquids, where we receive consideration for our services in the form of NGLs. For a keep-whole arrangement we replace the Btu content of the retained NGLs with natural gas purchases, also known as shrink replacement gas. For a percent-of-liquids arrangement, we deliver an agreed-upon percentage of the extracted NGLs and retain the remainder. Retained NGLs are referred to as our equity NGL production. Per-unit NGL margins are calculated based on sales of our own equity volumes at the processing plants. For the year ended December 31, 2020, approximately 20 percent of our NGL production volumes were under noncash commodity-based contracts.
Generally, our gathering and processing agreements are long-term agreements, with terms ranging from month-to-month to the life of the producing lease. Certain contracts include cost of service mechanisms that are designed to support a return on invested capital and allow our gathering rates to be adjusted, subject to specified caps in certain cases, to account for variability in volume, capital expenditures, commodity price fluctuations, compression and other expenses. We also have certain gas gathering and processing agreements with MVC, whereby the customer is obligated to pay a contractually determined fee based on any shortfall between the actual gathered and processed volumes and the MVC for a stated period.
Demand for gas gathering and processing services is dependent on producers’ drilling activities, which is impacted by the strength of the economy, commodity prices, and the resulting demand for natural gas by manufacturing and industrial companies and consumers. Our gathering, processing, and treating businesses do not have direct exposure to crude oil prices. Our on-shore natural gas gathering and processing businesses are substantially focused on gas-directed drilling basins rather than crude oil, with a broad diversity of basins and customers served. Declines in crude oil drilling would be expected to result in less associated natural gas production, which could drive more demand for natural gas produced from gas-directed basins we serve.
During 2020, our facilities gathered and processed gas and crude oil for approximately 230 customers. Our top ten customers accounted for approximately 73 percent of our gathering and processing fee revenues and NGL margins from our noncash commodity-based agreements. We believe counterparty credit concerns in our gathering and processing businesses are significantly mitigated by the physical nature of our services, where we gather at the wellhead and are therefore critical to a producer’s ability to move product to market.
Crude Oil Transportation and Production Handling Assets
Our crude oil transportation operations, which are presented in our Transmission & Gulf of Mexico segment as described under the heading “Business Segments,” earn revenues typically by volumetric-based fee arrangements. Revenue sources have historically included a combination of fixed-fee, volumetric-based fee, and cost reimbursement arrangements. Generally, fixed fees associated with the production at our Gulf Coast production handling facilities are recognized on a units-of-production basis. Certain fixed fees associated with the production at our Gulfstar One facility are recognized based on contractually determined maximum daily quantities. Our crude oil transportation business is supported mostly by major oil producers with long-cycle perspectives.
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Key variables for all of our businesses will continue to be:
Obstacles to our expansion efforts, including delays or denials of necessary permits and opposition to hydrocarbon-based energy development;
Producer drilling activities impacting natural gas supplies supporting our gathering and processing volumes;
Retaining and attracting customers by continuing to provide reliable services;
Revenue growth associated with additional infrastructure either completed or currently under construction;
Prices impacting our commodity-based activities;
Disciplined growth in our service areas.
BUSINESS SEGMENTS
Consistent with the manner in which our chief operating decision maker evaluates performance and allocates resources, our operations are conducted, managed, and presented in Part I of this Annual Report within the following reportable segments: Transmission & Gulf of Mexico, Northeast G&P, and West.
Our reportable segments are comprised of the following business activities:
Transmission & Gulf of Mexico is comprised of our interstate natural gas pipelines, Transco and Northwest Pipeline, as well as natural gas gathering and processing and crude oil production handling and transportation assets in the Gulf Coast region, including a 51 percent interest in Gulfstar One (a consolidated variable interest entity), which is a proprietary floating production system, a 50 percent equity-method investment in Gulfstream, and a 60 percent equity-method investment in Discovery.
Northeast G&P is comprised of our midstream gathering, processing, and fractionation businesses in the Marcellus Shale region primarily in Pennsylvania and New York, and the Utica Shale region of eastern Ohio, as well as a 65 percent interest in our Northeast JV (a consolidated variable interest entity) which operates in West Virginia, Ohio, and Pennsylvania, a 66 percent interest in Cardinal (a consolidated variable interest entity) which operates in Ohio, a 69 percent equity-method investment in Laurel Mountain, a 99 percent interest in Caiman II (a former equity-method investment which is a consolidated entity following our November 2020 acquisition of an additional ownership interest) which owns a 50 percent equity-method investment in Blue Racer, and Appalachia Midstream Investments, a wholly owned subsidiary that owns equity-method investments with an approximate average 66 percent interest in multiple gas gathering systems in the Marcellus Shale region.
West is comprised of our gas gathering, processing, and treating operations in the Rocky Mountain region of Colorado and Wyoming, the Barnett Shale region of north-central Texas, the Eagle Ford Shale region of south Texas, the Haynesville Shale region of northwest Louisiana, and the Mid-Continent region which includes the Anadarko, Arkoma, and Permian basins. This segment also includes our NGL and natural gas marketing business, storage facilities, an undivided 50 percent interest in an NGL fractionator near Conway, Kansas, a 50 percent equity-method investment in OPPL, a 50 percent equity-method investment in RMM, and a 20 percent equity-method investment in Targa Train 7.
Other includes minor business activities that are not reportable segments, as well as corporate operations.
Detailed discussion of each of our reporting segments follows. For a discussion of our ongoing expansion projects, see Part II, Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.
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Transmission & Gulf of Mexico
This segment includes the Transco interstate natural gas pipeline that extends from the Gulf of Mexico to the eastern seaboard, the Northwest Pipeline interstate natural gas pipeline, as well as natural gas gathering, processing and treating, crude oil production handling, and NGL fractionation assets within the onshore, offshore shelf, and deepwater areas in and around the Gulf Coast states of Texas, Louisiana, Mississippi, and Alabama. This segment also includes various petrochemical and feedstock pipelines in the Gulf Coast region.
Transco
Transco is an interstate natural gas transmission company that owns and operates a 9,800-mile natural gas pipeline system, which is regulated by the FERC, extending from Texas, Louisiana, Mississippi, and the Gulf of Mexico through Alabama, Georgia, South Carolina, North Carolina, Virginia, Maryland, Delaware, Pennsylvania, and New Jersey to the New York City metropolitan area. The system serves customers in Texas and 12 southeast and Atlantic seaboard states, including major metropolitan areas in Georgia, North Carolina, Washington, D.C., Maryland, New York, New Jersey, and Pennsylvania.
At December 31, 2020, Transco’s system had a system-wide delivery capacity totaling approximately 17.9 MMdth/d. During 2020, Transco completed one fully-contracted expansion and began partial early service on two additional fully-contracted expansions, which added more than 0.5 MMdth of firm transportation capacity per day to our pipeline. Transco’s system includes 57 compressor stations, four underground storage fields, and one LNG storage facility. Compression facilities at sea level-rated capacity total approximately 2.3 million horsepower.
Transco has natural gas storage capacity in four underground storage fields located on or near its pipeline system or market areas and operates two of these storage fields. Transco also has storage capacity in an LNG storage facility that it owns and operates. The total usable gas storage capacity available to Transco and its customers in such underground storage fields and LNG storage facility and through storage service contracts is approximately 194 MMdth of natural gas. At December 31, 2020, Transco’s customers had stored in its facilities approximately 148 MMdth of natural gas. Storage capacity permits our customers to inject gas into storage during the summer and off-peak periods for delivery during peak winter demand periods.
Northwest Pipeline
Northwest Pipeline is an interstate natural gas transmission company that owns and operates a 3,900-mile natural gas pipeline system, which is regulated by the FERC, extending from the San Juan basin in northwestern New Mexico and southwestern Colorado through Colorado, Utah, Wyoming, Idaho, Oregon, and Washington to a point on the Canadian border near Sumas, Washington. Northwest Pipeline provides services for markets in Washington, Oregon, Idaho, Wyoming, Nevada, Utah, Colorado, New Mexico, California, and Arizona, either directly or indirectly through interconnections with other pipelines.
At December 31, 2020, Northwest Pipeline’s system had long-term firm transportation and storage redelivery agreements with aggregate capacity reservations of approximately 3.8 MMdth/d. Northwest Pipeline’s system includes 42 transmission compressor stations having a combined sea level-rated capacity of approximately 473,000 horsepower.
Northwest Pipeline owns a one-third undivided interest in the Jackson Prairie underground storage facility in Washington and contracts with a third party for natural gas storage services in the Clay basin underground field in Utah. Northwest Pipeline also owns and operates an LNG storage facility in Washington. These storage facilities have an aggregate working natural gas storage capacity of 14.2 MMdth, which is substantially utilized for third-party natural gas. These natural gas storage facilities enable Northwest Pipeline to balance daily receipts and deliveries and provide storage services to customers.
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Gas Transportation, Processing, and Treating Assets
The following tables summarize the significant operated assets of this segment:
Offshore Natural Gas Pipelines
Inlet
PipelineCapacityOwnership
LocationMiles(Bcf/d)InterestSupply Basins
Consolidated:
Canyon Chief, including Blind Faith and Gulfstar extensionsDeepwater Gulf of Mexico1560.5100%Eastern Gulf of Mexico
NorphletDeepwater Gulf of Mexico580.3100%Eastern Gulf of Mexico
Other Eastern GulfOffshore shelf and other460.2100%Eastern Gulf of Mexico
SeahawkDeepwater Gulf of Mexico1150.4100%Western Gulf of Mexico
Perdido NorteDeepwater Gulf of Mexico1050.3100%Western Gulf of Mexico
Other Western GulfOffshore shelf and other1030.4100%Western Gulf of Mexico
Non-consolidated: (1)
Discovery
Central Gulf of Mexico5940.660%Western Gulf of Mexico
Natural Gas Processing Facilities
NGL
InletProduction
CapacityCapacityOwnership
Location(Bcf/d)(Mbbls/d)InterestSupply Basins
Consolidated:
Markham
Markham, TX0.545100%Western Gulf of Mexico
Mobile Bay
Coden, AL0.735100%Eastern Gulf of Mexico
Non-consolidated: (1)
DiscoveryLarose, LA0.63260%Western Gulf of Mexico
_____________
(1)Includes 100 percent of the statistics associated with operated equity-method investments.
Crude Oil Transportation and Production Handling Assets
In addition to our natural gas assets, we own and operate four deepwater crude oil pipelines and own production platforms serving the deepwater in the Gulf of Mexico. Our offshore floating production platforms provide centralized services to deepwater producers such as compression, separation, production handling, water removal, and pipeline landings.
The following tables summarize the significant crude oil transportation pipelines and production handling platforms of this segment:
 Crude Oil Pipelines
 PipelineCapacityOwnership
 Miles(Mbbls/d)InterestSupply Basins
Consolidated:
Mountaineer, including Blind Faith and Gulfstar extensions
155150100%Eastern Gulf of Mexico
BANJO
5790100%Western Gulf of Mexico
Alpine
9685100%Western Gulf of Mexico
Perdido Norte
74150100%Western Gulf of Mexico

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 Production Handling Platforms
Crude/NGL
Gas InletHandling
 CapacityCapacityOwnership
 (MMcf/d)(Mbbls/d)InterestSupply Basins
Consolidated:
Devils Tower
11060100%Eastern Gulf of Mexico
Gulfstar I FPS (1)
1728051%Eastern Gulf of Mexico
Non-consolidated: (2)
Discovery
751060%Western Gulf of Mexico
__________
(1)Statistics reflect 100 percent of the assets from our 51 percent interest in Gulfstar One.
(2)Includes 100 percent of the statistics associated with operated equity-method investments.

Transmission & Gulf of Mexico Operating Statistics
202020192018
Consolidated:
Interstate natural gas pipeline throughput (Tbtu/d)15.1 15.3 14.0 
Gathering volumes (Bcf/d) 0.25 0.25 0.26 
Plant inlet natural gas volumes (Bcf/d) 0.48 0.54 0.50 
NGL production (Mbbls/d) (2)29 32 32 
NGL equity sales (Mbbls/d) (2)
Crude oil transportation (Mbbls/d) (2)121 136 140 
Non-consolidated: (1)
Interstate natural gas pipeline throughput (Tbtu/d)1.2 1.2 1.3 
Gathering volumes (Bcf/d)0.30 0.36 0.26 
Plant inlet natural gas volumes (Bcf/d)0.30 0.36 0.27 
NGL production (Mbbls/d) (2)21 25 20 
NGL equity sales (Mbbls/d) (2)
_____________
(1)Includes 100 percent of the volumes associated with operated equity-method investments.
(2)Annual average Mbbls/d.
Certain Equity-Method Investments
Gulfstream
Gulfstream is a 745-mile interstate natural gas pipeline system extending from the Mobile Bay area in Alabama to markets in Florida, which has a capacity to transport 1.3 Bcf/d. We own, through a subsidiary, a 50 percent equity-method investment in Gulfstream. We share operating responsibilities for Gulfstream with the other 50 percent owner.
Discovery
We own a 60 percent interest in and operate the facilities of Discovery. Discovery’s assets include a 600 MMcf/d cryogenic natural gas processing plant near Larose, Louisiana, a 32 Mbbls/d NGL fractionator plant near Paradis, Louisiana, and a 594-mile offshore natural gas gathering and transportation system in the Gulf of Mexico.
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Discovery’s mainline has a gathering inlet capacity of 600 MMcf/d. Discovery’s assets also include a crude oil production handling platform with capacity of 10 Mbbls/d and gas handling and separation capacity of 75 MMcf/d.
Northeast G&P
This segment includes our natural gas gathering, compression, processing, and NGL fractionation businesses in the Marcellus and Utica Shale regions in Pennsylvania, West Virginia, New York, and Ohio.

The following tables summarize the significant operated assets of this segment:
 Natural Gas Gathering Assets
Inlet
 PipelineCapacityOwnership
 LocationMiles(Bcf/d)InterestSupply Basins
Consolidated:
Ohio Valley Midstream (1)Ohio, West Virginia, & Pennsylvania2160.865%Appalachian
Utica East Ohio Midstream (1) (2)Ohio530.565%Appalachian
Susquehanna Supply HubPennsylvania & New York4624.3100%Appalachian
Cardinal (1)Ohio3780.866%Appalachian
FlintOhio950.5100%Appalachian
Non-consolidated: (3)
Bradford Supply HubPennsylvania7334.066%Appalachian
Marcellus SouthPennsylvania & West Virginia3251.068%Appalachian
Laurel MountainPennsylvania1,1450.969%Appalachian
Blue RacerWest Virginia & Ohio7231.550%Appalachian
 Natural Gas Processing Facilities
NGL
InletProduction
 CapacityCapacityOwnership
 Location(Bcf/d)(Mbbls/d)InterestSupply Basins
Consolidated: (1)
Fort BeelerMarshall County, WV0.56265%Appalachian
Oak GroveMarshall County, WV0.45065%Appalachian
KensingtonColumbiana Co., OH0.66865%Appalachian
LeesvilleCarroll Co., OH0.21865%Appalachian
Non-Consolidated: (3)
BerneMonroe Co., OH0.46050%Appalachian
NatriumMarshall Co., WV0.812050%Appalachian
_____________
(1)Statistics reflect 100 percent of the assets from our 65 percent ownership in our Northeast JV and 66 percent ownership of Cardinal gathering system.
(2)UEOM inlet capacity consists of 1.3 Bcf/d of a high pressure gathering pipeline that delivers Cardinal gathering volumes to UEOM processing facilities. The listed inlet capacity of 0.5 Bcf/d is incremental capacity to the Cardinal gathering capacity of 0.8 Bcf/d.
(3)Includes 100 percent of the statistics associated with operated equity-method investments.
Other NGL Operations
We own and operate a 43 Mbbls/d NGL fractionation facility at Moundsville, West Virginia, de-ethanization and condensate facilities at our Oak Grove processing plant, a condensate stabilization facility near our Moundsville fractionator, and an ethane transportation pipeline. Our Oak Grove de-ethanizer is capable of handling up to approximately 80 Mbbls/d of mixed NGLs to extract up to approximately 40 Mbbls/d of ethane. Our condensate
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stabilizers are capable of handling approximately 17 Mbbls/d of field condensate. We also own and operate 44 Mbbls/d of condensate stabilization capacity, a 135 Mbbls/d NGL fractionation facility, approximately 970,000 barrels of NGL storage capacity, and other ancillary assets, including loading and terminal facilities in Ohio.
NGLs are extracted from the natural gas stream in our Oak Grove and Fort Beeler cryogenic processing plants. Ethane produced at our de-ethanizer is transported to markets via our 50-mile ethane pipeline from Oak Grove to Houston, Pennsylvania. The remaining mixed NGL stream from the de-ethanizer is then transported via pipeline and fractionated at either our Moundsville or Harrison County, Ohio, fractionation facility. The resulting products are then transported on truck or rail. Ohio Valley Midstream provides residue natural gas take away options for our customers with interconnections to three interstate transmission pipelines.
Northeast G&P Operating Statistics
202020192018
Consolidated:
Gathering volumes (Bcf/d)4.31 4.24 3.63
Plant inlet natural gas volumes (Bcf/d)1.32 1.040.52
NGL production (Mbbls/d) (1)101 7646
NGL equity sales (Mbbls/d) (1)34
Non-consolidated: (2)
Gathering volumes (Bcf/d)4.78 4.293.76
__________
(1)    Annual average Mbbls/d.
(2)    Includes 100 percent of the volumes associated with operated equity-method investments, including the Laurel Mountain Midstream partnership; and the Bradford Supply Hub and a portion of the Marcellus South Supply Hub within Appalachia Midstream Investments. Beginning November 18, 2020, we operate Blue Racer. Blue Racer gathering volumes of 1.38 Bcf/d, plant inlet natural gas volumes of 0.95 Bcf/d, NGL production of 65 Mbbls/d, and NGL equity sales of 6 Mbbls/d have been excluded.
Acquisition of UEOM and formation of Northeast JV
As of December 31, 2018, we owned a 62 percent interest in UEOM which we accounted for as an equity-method investment. On March 18, 2019, we signed and closed the acquisition of the remaining 38 percent interest in UEOM. As a result of acquiring this additional interest, we obtained control of and now consolidate UEOM. (See Note 3 – Acquisitions and Divestitures of Notes to Consolidated Financial Statements).
In June 2019, we contributed our consolidated interests in UEOM and our Ohio Valley midstream business to a newly formed partnership, and we retained 65 percent ownership of, as well as operate and consolidate, the Northeast JV business.
Certain Equity-Method Investments
Appalachia Midstream Investments    
Through our Appalachia Midstream Investments, we operate 100 percent of and own an approximate average 66 percent interest in the Bradford Supply Hub gathering system and own an approximate average 68 percent interest in the Marcellus South gathering system, together which consist of approximately 1,058 miles of gathering pipeline in the Marcellus Shale region with the capacity to gather 5,031 MMcf/d of natural gas. The majority of our volumes in the region are gathered from northern Pennsylvania, southwestern Pennsylvania, and the northwestern panhandle of West Virginia in core areas of the Marcellus Shale. We operate the assets under long-term, 100 percent fixed-fee gathering agreements that include significant acreage dedications and, in the Bradford Supply Hub, a cost of service mechanism. Additionally, some Marcellus South agreements have MVCs.
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Laurel Mountain
We own a 69 percent interest in a joint venture, Laurel Mountain, that includes a 1,145-mile gathering system that we operate in western Pennsylvania with the capacity to gather 0.9 Bcf/d of natural gas. Laurel Mountain has a long-term, dedicated, volumetric-based fee agreement, with exposure to natural gas prices, to gather the anchor customer’s production in the western Pennsylvania area of the Marcellus Shale.
Blue Racer
As of December 31, 2019, we effectively owned a 29 percent indirect interest in Blue Racer through our 58 percent interest in Caiman II, whose primary asset is a 50 percent interest in Blue Racer. On November 18, 2020, we paid $157 million, net of cash acquired, to acquire an additional 41 percent ownership interest in Caiman II. We now control and consolidate Caiman II, reporting the 50 percent interest in Blue Racer as an equity-method investment.
Blue Racer is a joint venture to own, operate, develop, and acquire midstream assets in the Utica Shale and certain adjacent areas in the Marcellus Shale. Blue Racer’s assets include 723 miles of gathering pipelines, and the Natrium complex in Marshall County, West Virginia, with a cryogenic processing capacity of 800 MMcf/d and fractionation capacity of approximately 134 Mbbls/d. Blue Racer also owns the Berne complex in Monroe County, Ohio, with a cryogenic processing capacity of 400 MMcf/d, and NGL and condensate pipelines connecting Natrium to Berne. Blue Racer provides gathering, processing, and marketing service primarily under percentage of liquids and fixed fee agreements.
West
Gas Gathering, Processing, and Treating Assets
The following tables summarize the significant operated assets of this segment:
 Natural Gas Gathering Assets
 LocationPipeline MilesInlet Capacity (Bcf/d)Ownership InterestSupply Basins/Shale Formations
Consolidated:
WamsutterWyoming2,2650.7100%Wamsutter
Southwest WyomingWyoming1,6140.5100%Southwest Wyoming
PiceanceColorado3521.8(1)Piceance
Barnett ShaleTexas8400.5100%Barnett Shale
Eagle Ford ShaleTexas1,2800.5100%Eagle Ford Shale
Haynesville ShaleLouisiana6291.8100%Haynesville Shale
PermianTexas1030.1100%Permian
Mid-ContinentOklahoma & Texas2,2480.9100%Miss-Lime, Granite Wash, Colony Wash, Arkoma
Non-consolidated: (2)
Rocky Mountain MidstreamColorado2000.650%Denver-Julesburg

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 Natural Gas Processing Facilities
NGL
InletProduction
 CapacityCapacityOwnership
 Location(Bcf/d)(Mbbls/d)InterestSupply Basins
Consolidated:
Echo SpringsEcho Springs, WY0.758100%Wamsutter
OpalOpal, WY1.147100%Southwest Wyoming
Willow CreekRio Blanco County, CO0.530100%Piceance
ParachuteGarfield County, CO1.16100%Piceance
Non-consolidated: (2)
Fort LuptonColorado0.35050%Denver-Julesburg
Keenesburg IColorado0.24050%Denver-Julesburg
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(1)Includes our 60 percent ownership of a gathering system in the Ryan Gulch area with 140 miles of pipeline and 0.2 Bcf/d of inlet capacity, and our 67 percent ownership of a gathering system at Allen Point with 8 miles of pipeline and 0.1 Bcf/d of inlet capacity. We operate both systems. We own and operate 100 percent of the balance of the Piceance gathering assets.
(2)Includes 100 percent of the statistics associated with operated equity-method investments.
Marketing Services
We market gas and NGL products to a wide range of users in the energy and petrochemical industries. The NGL marketing business transports and markets our equity NGLs from the production at our processing plants, and also markets NGLs on behalf of third-party NGL producers, including some of our fee-based processing customers, and the NGL volumes owned by Discovery and RMM. The NGL marketing business bears the risk of price changes in these NGL volumes while they are being transported to final sales delivery points. In order to meet sales contract obligations, we may purchase products in the spot market for resale.
Other NGL Operations
We own interests in and/or operate NGL fractionation and storage assets in central Kansas near Conway. These assets include a 50 percent interest in an NGL fractionation facility with capacity of slightly more than 100 Mbbls/d and we own approximately 20 million barrels of NGL storage capacity. We also own a 189-mile NGL pipeline from our fractionator near Conway, Kansas, to an interconnection with a third-party NGL pipeline system in Oklahoma.
West Operating Statistics
202020192018
Consolidated: (1)
Gathering volumes (Bcf/d)3.33 3.52 4.27 
Plant inlet natural gas volumes (Bcf/d)1.25 1.48 2.01 
NGL production (Mbbls/d) (2)49 54 84 
NGL equity sales (Mbbls/d) (2)22 22 33 
Non-Consolidated: (3)
Gathering volumes (Bcf/d)0.25 0.20 0.08 
Plant inlet natural gas volumes (Bcf/d)0.25 0.20 0.08 
NGL production (Mbbls/d) (2)23 12 
________________
(1)    2020 and 2019 volumes reflect the absence of Four Corners assets due to the sale in October 2018.
(2)    Annual average Mbbls/d.
(3)    Includes 100 percent of the volumes associated with operated equity-method investments, including RMM and Jackalope. Jackalope was a consolidated entity in first- and second-quarter 2018, an equity-method investment during third- and fourth-quarter 2018 as well as first-quarter 2019, and sold effective with second-quarter 2019.
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Sale of Four Corners Assets
In October 2018, we completed the sale of our natural gas gathering and processing assets in the Four Corners area of New Mexico and Colorado. The system was comprised of 3,742 miles of gathering pipeline with 1.8 Bcf/d of gas gathering inlet capacity and two processing facilities with a combined 0.7 Bcf/d of natural gas processing inlet capacity and 41 Mbbls/d of NGL production capacity.
Certain Equity-Method Investments
Overland Pass Pipeline
We also operate and own a 50 percent interest in OPPL. OPPL is capable of transporting 255 Mbbls/d of NGLs and includes approximately 1,035 miles of NGL pipeline extending from Opal, Wyoming, to the Mid-Continent NGL market center near Conway, Kansas, along with extensions into the Piceance and Denver-Julesberg basins in Colorado and the Bakken Shale in the Williston basin in North Dakota. Our equity NGL volumes from our Wyoming plants and our Willow Creek facility in Colorado are dedicated for transport on OPPL under a long-term transportation agreement. NGL volumes from our RMM equity-method investment are also transported on OPPL.
Rocky Mountain Midstream
During the third quarter of 2018, our joint venture, RMM, purchased a natural gas and crude oil gathering and natural gas processing business in Colorado’s Denver-Julesburg basin. As of December 31, 2020, we operate and own 50 percent of RMM. RMM includes a natural gas gathering pipeline and an approximate 80-mile crude oil transportation pipeline. It also includes crude oil storage assets.
Targa Train 7
We own a 20 percent interest in Targa Train 7, a Mt. Belvieu fractionation train, which was placed into service in the first quarter of 2020.
Other
Other includes certain previously owned operations, minor business activities that are not reportable segments, as well as corporate operations.
REGULATORY MATTERS
FERC
Our gas pipeline interstate transmission and storage activities are subject to FERC regulation under the Natural Gas Act of 1938 (NGA) and under the Natural Gas Policy Act of 1978, and, as such, our rates and charges for the transportation of natural gas in interstate commerce, accounting, and the extension, enlargement, or abandonment of our jurisdictional facilities, among other things, are subject to regulation. Each of our gas pipeline companies holds certificates of public convenience and necessity issued by the FERC authorizing ownership and operation of all pipelines, facilities, and properties for which certificates are required under the NGA. FERC Standards of Conduct govern how our interstate pipelines communicate and do business with gas marketing employees. Among other things, the Standards of Conduct require that interstate gas pipelines not operate their systems to preferentially benefit gas marketing functions.
FERC regulation requires all terms and conditions of service, including the rates charged, to be filed with and approved by the FERC before any changes can go into effect. Our interstate gas pipeline companies establish rates through the FERC’s ratemaking process. In addition, our interstate gas pipelines may enter into negotiated rate agreements where cost-based recourse rates are made available. Key determinants in the FERC ratemaking process include:
Costs of providing service, including depreciation expense;
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Allowed rate of return, including the equity component of the capital structure and related income taxes;
Contract and volume throughput assumptions.
The allowed rate of return is determined in each rate case. Rate design and the allocation of costs between the reservation and commodity rates also impact profitability. As a result of these proceedings, certain revenues previously collected may be subject to refund.
We also own interests in and operate natural gas liquids pipelines that are regulated by various federal and state governmental agencies. Services provided on our interstate natural gas liquids pipelines are subject to regulation under the Interstate Commerce Act by the FERC, which has authority over the terms and conditions of service; rates, including depreciation and amortization policies; and initiation of service. Our intrastate natural gas liquids pipelines providing common carrier service are subject to regulation by various state regulatory agencies.
Pipeline Safety
Our gas pipelines are subject to the Natural Gas Pipeline Safety Act of 1968, as amended, the Pipeline Safety Improvement Act of 2002, the Pipeline Safety, Regulatory Certainty, and Jobs Creation Act of 2011 (Pipeline Safety Act), and the Protecting Our Infrastructure of Pipelines and Enhancing Safety Act of 2016, which regulate safety requirements in the design, construction, operation, and maintenance of interstate natural gas transmission facilities. The United States Department of Transportation Pipeline and Hazardous Materials Safety Administration (PHMSA) administers federal pipeline safety laws.
Federal pipeline safety laws authorize PHMSA to establish minimum safety standards for pipeline facilities and persons engaged in the transportation of gas or hazardous liquids by pipeline. These safety standards apply to the design, construction, testing, operation, and maintenance of gas and hazardous liquids pipeline facilities affecting interstate or foreign commerce. PHMSA has also established reporting requirements for operators of gas and hazardous liquid pipeline facilities, as well as provisions for establishing the qualification of pipeline personnel and requirements for managing the integrity of gas transmission and distribution lines and certain hazardous liquid pipelines. To ensure compliance with these provisions, PHMSA performs pipeline safety inspections and has the authority to initiate enforcement actions.
In 2016, PHMSA published a proposed rulemaking that would impose new or more stringent requirements for certain natural gas pipelines including, expanding certain of PHMSA’s current regulatory safety programs for natural gas lines in high-population areas (also known as moderate consequence areas (MCAs)) that do not qualify as high-consequence areas (HCAs) and requiring maximum allowable operating pressure (MAOP) validation through re-verification of all historical records for pipelines in service, which may require natural gas pipelines installed before 1970 (previously excluded from certain pressure testing obligations) to be pressure tested. However, PHMSA has since decided to split this proposed rule (Mega Rule), into three separate rulemaking proceedings. The first of these three rulemakings, relating to onshore gas transmission pipelines, was published as a final rule on October 1, 2019, and imposes numerous requirements, including MAOP reconfirmation, the periodic assessment of additional pipeline mileage outside of HCAs, the reporting of exceedances of MAOP, and the consideration of seismicity as a risk factor in integrity management. In accordance with the final rule, we have developed new procedures and updated our existing pipeline safety program to facilitate meeting all requirements within the time frames stated. The remaining rulemakings comprising the Mega Rule are expected to be issued in 2021 and will include revised pipeline repair criteria as well as more stringent corrosion control requirements.
PHMSA also published new or more stringent rules for onshore hazardous liquids transportation lines in October 2019 requiring integrity assessments on all onshore pipe that accommodate inline inspection tools.
We are also expecting additional regulations due to new pipeline safety legislation finalized in December 2020 that reauthorized PHMSA pipeline safety programs. The new legislation includes mandates for PHMSA to publish final rules for advanced leak detection for gas pipelines, additional repair criteria for gas and hazardous liquids pipelines, updated operating and maintenance standards requirements applicable to large-scale liquefied natural gas facilities, certain Coastal Waters and Coastal Beaches to be designated as USA ecological resources for purposes of
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determining whether a hazardous liquid pipeline is in a high consequence area, and the gas gathering portion of the proposed Mega Rule.
New regulations adopted by PHMSA may impose more stringent requirements applicable to integrity management programs and other pipeline safety aspects of our operations, which could cause us to incur increased capital and operating costs and operational delays.
Pipeline Integrity Regulations
We have an enterprise-wide Gas Integrity Management Plan that we believe meets the PHMSA final rule that was issued pursuant to the requirements of the Pipeline Safety Improvement Act of 2002. The rule requires gas pipeline operators to develop an integrity management program for gas transmission pipelines that could affect HCAs in the event of pipeline failure. The integrity management program includes a baseline assessment plan along with periodic reassessments to be completed within required time frames. In meeting the integrity regulations, we have identified HCAs and developed baseline assessment plans. Ongoing periodic reassessments and initial assessments of any new HCAs have been completed. We estimate that the cost to be incurred in 2021 associated with this program to be approximately $105 million. Management considers costs associated with compliance with the rule to be prudent costs incurred in the ordinary course of business and, therefore, recoverable through Northwest Pipeline’s and Transco’s rates.
We have an enterprise-wide Liquid Integrity Management Plan that we believe meets the PHMSA final rule that was issued pursuant to the requirements of the Pipeline Safety Improvement Act of 2002. The rule requires liquid pipeline operators to develop an integrity management program for liquid transmission pipelines that could affect HCAs in the event of pipeline failure. The integrity management program includes a baseline assessment plan along with periodic reassessments expected to be completed within required time frames. In meeting the integrity regulations, we utilized government defined HCAs and developed baseline assessment plans. We completed assessments within the required time frames. We estimate that the cost to be incurred in 2021 associated with this program will be approximately $3 million. Ongoing periodic reassessments and initial assessments of any new HCAs are expected to be completed within the time frames required by the rule. Management considers the costs associated with compliance with the rule to be prudent costs incurred in the ordinary course of business.
State Gathering Regulations