Investor Presentation October 2012

Forward Looking Statements

This presentation contains forward-looking statements and projections, made in reliance on the safe harbor provisions of the Private Securities Litigation Reform Act of 1995, regarding future events, occurrences, circumstances, activities, performance, outcomes and results of Crestwood Midstream Partners LP (“Crestwood” or “CMLP”). Although these statements reflect the current views, assumptions and expectations of Crestwood’s management, the matters addressed herein are subject to numerous risks and uncertainties, which could cause actual activities, performance, outcomes and results to differ materially from those indicated. However, a variety of factors could cause actual results to materially differ from Crestwood’s current expectations in financial condition, results of operations and cash flows including, without limitation, changes in general economic conditions; fluctuations in natural gas prices; the extent and success of drilling efforts, as well as the extent and quality of natural gas volumes produced within proximity of our assets; failure or delays by our customers in achieving expected production in their natural gas projects; competitive conditions in our industry; actions or inactions taken or non-performance by third parties, including suppliers, contractors, operators, processors, transporters and customers; our ability to consummate acquisitions, successfully integrate acquired businesses, and realize any cost savings and other synergies from any acquisition; fluctuations in the value of certain of our assets and liabilities; changes in the availability and cost of capital; operating hazards, natural disasters, weather-related delays, casualty losses and other matters beyond our control; timely receipt of necessary government approvals and permits, our ability to control the costs of construction, including costs of materials, labor and rights-of-way and other factors that may impact our ability to complete projects within budget and on schedule; the effects of existing and future laws and governmental regulations, including environmental and climate change requirements; the effects of existing and future litigation; and risks related to our substantial indebtedness; and other factors disclosed in Crestwood’s filings with the Securities and Exchange Commission. The forward-looking statements included in this presentation are made only as of the date of this presentation, and we undertake no obligation to update any of these forward-looking statements to reflect new information, future events or circumstances except to the extent required by applicable law.

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Crestwood Overview Crestwood Midstream Partners LP: (NYSE: CMLP)

General Partner owned by First Reserve and Crestwood Management team

~$2 billion enterprise value; current yield ~ 8.5%

Midstream services: gathering, processing, treating and compression

95% fixed-fee portfolio – stable cash flows

Leading midstream player in Marcellus, Granite Wash, Barnett, Avalon, Fayetteville, Haynesville unconventional plays

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Experienced Management Team and Sponsor Crestwood Management Team

World’s leading private equity firm specializing in the energy industry Over 25 years of investing experience solely in the energy industry Currently investing out of $8.8 billion Fund XII

$615 MM equity investment in Crestwood Highly incentivized to support the growth of CMLP through additional

investments at Holdco, joint ventures with CMLP or drop downs to CMLP

34 years Industry Experience President and CEO and a Director of Enterprise Products Partners L.P. (NYSE:EPD) Chairman, President and CEO of GulfTerra Energy Partners, L.P. (NYSE:GTM) President of El Paso Field Services (El Paso Corporation; NYSE:EP)

24 years Industry Experience Chief Financial Officer of TEPPCO Partners, LP (NYSE:TPP) Vice President of Strategic Planning at Enterprise Product Partners, LP (NYSE:EPD) Vice President and Chief Financial Officer of GulfTerra Energy Partners (NYSE:GTM)

32 years Industry Experience Senior Vice President of Crosstex Energy, L.P. (NASDAQ: XTEX) Senior Vice President for Enterprise Products Partners, LP (NYSE: EPD) Responsible for gas processing, fractionation and marketing in El Paso Corporation (NYSE: EP)

16 years Industry Experience Vice President of Project Development & Engineering for El Paso Corporation (NYSE: EP) Director of Marketing & Asset Optimization for Tennessee Gas Pipeline – El Paso (NYSE: EP) Manager of Business Development & Strategy for Southern Natural Gas - El Paso (NYSE: EP)

Robert G. Phillips Chairman, President and CEO

William G. Manias Senior Vice President and Chief Financial Officer

Joel D. Moxley Senior Vice President – Chief Operating Officer

J. Heath Deneke Senior Vice President – Chief Commercial Officer

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Investment Thesis

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$200+ billion anticipated midstream infrastructure required to support upstream development of unconventional assets over the next 2-3 decades

Current Crestwood Operating Areas

US Shale Plays

Future Greenfield

Development Crestwood Midstream Partners LP

(NYSE: CMLP)

Enterprise Value: $2.1 Bn

42% LP/GP

Public and Class C

Unit holders

Crestwood Holdings LLC (Holdco)

First Reserve and

Management

58% LP

Strong GP/LP Alignment of Interest

Fayetteville Shale

CMM Marcellus

Shale

Granite Wash

Haynesville Shale

Barnett Shale

65% Interest

Avalon Shale

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Barnett Shale Rich Dry

35% Interest

Future Drop-Down

Phase I: Initial Acquisitions

Acquired diverse portfolio of midstream assets across leading shale plays

Achieved critical mass in operations at ~1 Bcf/d throughput

Phase II: M&A Drop-Downs

Equity support from First Reserve for high-growth acquisitions

Phase III: Greenfield Development

Development team aggressively pursuing opportunities

Drop-Down to CMLP once in-service and generating cash flow

Evolving Growth Strategy

Track Record of Value Creation Since establishing Crestwood Holdings, six midstream acquisitions with an aggregate transaction value of ~$1.6 billion completed

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Crestwood Holdings Formed

KGS Barnett Shale

Acquisition

CMLP issues 1.8MM

common units

Acquisition of Fayetteville Shale and Granite Wash

assets

Acquisition of Haynesville/Bossier

Shale assets

Formation of CMM joint venture and

acquisition of Marcellus Shale

assets

CMLP issues 6.2MM Class C

units and $200MM of

Senior Notes

Acquisition of Avalon

Shale assets

CMLP issues 3.5MM

common units

Crestwood Holdings

establishes $400MM term loan (replaced existing loan)

Crestwood Joint Venture establishes

$200MM credit facility

May 2010

July 2010

February 2011

November 2011

April 2011

May 2011

March 2012

October 2010

January 2012

FRC & Management Initial Equity and

Crestwood Holdings establishes

$180MM term loan

30% Total Return to CMLP Unitholders: July 22, 2010 to Sep 30, 2012 (1)

(1) CMLP total return since Crestwood Holdings’ acquisition of KGS announced on 7/22/10, assuming distribution reinvestment. Source: Bloomberg

Bolt-on Acquisition in

liquids-rich area of

Barnett Shale

July 2012

CMLP issues 4.6MM

common units

Established Field Services Platform

Avalon Shale

Granite Wash

13,000+ acres; growing

rich-gas play

55,000 acres; emerging

liquids-rich area

Fayetteville Shale

140,000+ acres; 10-20 year

contracts; 55% developed

Barnett Shale

20,000 acres; 5-10 year contracts;

HBP phase

Haynesville Shale

100,000+ acres; 15 year contracts; 10-20% developed

127,000+ acres; 20 year contracts; 7-year minimum volume contract

Marcellus Shale

Key Operating Statistics (1)

Miles of Pipeline 830

Processing Plants 5

Compression HP (000’s) 226

Gathering Volume (MMcf/d) 965

Processing Volume (MMcf/d) 220

(1) As of 10/1/12. Includes 100% of Crestwood Marcellus Midstream joint venture

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Growth Drivers for 2012 / 2013 Crestwood built solid operating platform across major shale

plays through 6 acquisitions (2010-2012)

Lower natural gas prices have slowed development of dry gas systems in Barnett dry, Fayetteville and Haynesville shale plays

2012-2013 growth will come from rich gas areas including Barnett, Marcellus and Granite Wash systems due to strong producer drilling economics (NGL upgrade) which drive development activity

Additional accretive bolt-on acquisitions and drop-downs from CMM and Holdco will supplement growth 2013+

New green field development projects will position Crestwood for long term growth 2014+

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Recent Acquisition - Barnett Rich Gas CMLP’s largest operations are located

in the Barnett Shale

$87MM bolt on acquisition from Devon Energy substantially increases CMLP’s gathering and processing assets in the rich gas portion of the Barnett shale

~5%-8% distributable cash flow accretion in 2H 2012 and 2013

20-year fixed-fee contract with Devon 20,500 acreage dedication Annual fee escalator

74 mile gathering system and 100 MMcf/d gas processing plant

Current volumes of ~78 MMcf/d (1)

Transaction closed on 8/24/12

Corvette Plant

Devon Plant

Cowtown Plant

Legend Processing Plants CMLP Cowtown Gathering System

Devon Gathering System

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(1) As of 10/1/12

Recent Acquisition - Marcellus Shale Marcellus Shale in the Northeast US is the

industry’s fasting growing natural gas play

Crestwood Marcellus Midstream (CMM) is a joint venture between CMLP and Crestwood Holdings formed to acquire gathering assets

CMM Ownership: Crestwood Holdings 65%; CMLP 35% with quarterly distributions

$377MM acquisition by CMM in March 2012

~340 MMcf/d currently flowing through CMM systems (1)

$200MM revolver at CMM to fund growth capital needs to build-out system

20-year fixed-fee contract with Antero Resources 127,000 acre area of dedication 7-year minimum volume guarantee Annual fee escalator

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Rich Gas Area Dry Gas Area

Legend Area of Dedication (AOD) Planned MWE Sherwood Plant Pipeline in Service at YE 2012

Planned Pipeline (2013 – 2016) Existing and Planned Third Party Pipeline

(1) As of 10/1/12

Development Update - Granite Wash Granite Wash is an expanding

unconventional play located in the Texas Panhandle

CMLP acquired gathering and processing assets in April 2011

Le Norman Operating, a First Reserve portfolio E&P company, is developing acreage adjacent to CMLP facilities

First two Le Norman completions IP’d at combined rate of ~10.5 MMcf/d and ~1,600 Bpd of oil

Le Norman drilling plan Phase 1: 13 wells over next 18 months

(37 locations over next 5 years) Phase 2: Potential 37,000 acreage

expansion based on 2H 2012 and 2013 drilling results

Potential to exceed current Indian Creek plant capacity of 38 MMcf/d

Phase 1

Phase 2

Current

Indian Creek Plant

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$1.39 $1.52

$1.66

$1.87 $2.02

$1.00

$1.25

$1.50

$1.75

$2.00

$2.25

2008 2009 2010 2011 2012Guidance

$148

$55

$149

$462

$250

$-

$100

$200

$300

$400

$500

2008 2009 2010 2011 2012Guidance

$ MM

$50 $64

$77

$110 $128

$-

$25

$50

$75

$100

$125

$150

2008 2009 2010 2011 2012Guidance

$ MM

193 257

343

570

900

0

200

400

600

800

1,000

2008 2009 2010 2011 2012Guidance

MMcf/day

Building Impressive Growth Story Gathering Volumes Adjusted EBITDA

Capital Expenditures Distributions Paid per Unit

(1) Represents midpoint of 2012 guidance. Volume data includes 100% of CMM gathering volumes since acquisition (~300 MMcf/d). (2) Adjusted EBITDA includes net 35% ownership contribution from CMM. (3) Does not include additional acquisitions after 8/24/12.

(1) (2)

(3)

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Key Financial Metrics - 1H 2012

2012 2011 % Increase

Gathering (MMcf/d) (1) 843.4 499.0 + 69%Processing (MMcf/d) 145.8 141.0 + 3%

Revenues ($MMs) $101.9 $87.9 + 16%Adjusted EBITDA ($MMs) $56.9 $50.4 + 13%

Distributions per Unit $1.00 $0.90 + 11%

Total Debt ($MMs) $550.5 $437.5Debt to Capitalization 46% 48%

Debt to Pro Forma LTM EBITDA 4.1x 4.3xBorrowing Capacity ($MMs) $165.5 $185.1

(1) 2012 includes 257 MMcf/d of gathering volumes by CMM, which represents 100% of gathering volumes since acquistion on March 26, 2012.(2) As defined in CMLP's credit agreement. Debt includes capital lease obligations, $8.0 million deferred purchase of Tristate acquisition that will be paid Q4 2012,

$90 million for the pending Devon Acquisition, offset by $116.9 million of equity proceeds received in Q3 2012. Latest twelve months EBITDA is pro forma for theTristate Acquisition and the pending Devon Acquisition.

Six Months Ended June 30,

Operating Statistics:

Leverage Metrics (2):

Key Investment Considerations

Over $600 million invested by First Reserve and Crestwood Management

Highly experienced management team with history of creating investor value

Long term contracts with top-tier shale producers (Antero, BHP Billiton, BP, Chesapeake, Devon, Exxon Mobil, Quicksilver)

95% fixed-fee portfolio – stable cash flows Operations in leading unconventional plays (Marcellus,

Granite Wash, Barnett, Avalon, Fayetteville, Haynesville)

Bolt-on acquisitions with operating synergies Business development team to generate greenfield

infrastructure investment opportunities Drop-down opportunities from the general partner

Established Field Services

Platform

Visible Growth

Strategy

Strong GP/LP Alignment Of Interest

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Non-GAAP Financial Measures

The following slides of this presentation provide reconciliations of the non-GAAP financial measures adjusted EBITDA to its most directly comparable financial measures calculated and presented in accordance with generally accepted accounting principles in the United States of America ("GAAP"). Our non-GAAP financial measures should not be considered as alternatives to GAAP measures such as net income or operating income or any other GAAP measure of liquidity or financial performance. We define adjusted EBITDA as net income from continuing operations adjusted for interest expense, income taxes, depreciation, amortization and accretion expense and certain non-recurring expenses, including but not limited to items such as transaction related expenses and gains/losses on the exchange of property, plant and equipment. Adjusted EBITDA is commonly used as a supplemental financial measure by senior management and by external users of our financial statements, such as investors, research analysts and rating agencies, to assess the financial performance of our assets without regard to financing methods, capital structures or historical cost basis.

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Non-GAAP Reconciliations

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2008 2009 2010 2011 2011 2012

Total revenues 76,084$ 95,881$ 113,590$ 205,820$ 87,915$ 101,935$

Product purchases - - - (38,787) (12,528) (16,414)

Operations and maintenance expense (19,395) (21,968) (25,702) (36,303) (15,592) (18,598)

General and administrative expense (6,407) (9,676) (17,657) (24,153) (12,430) (13,674)

Gain from exchange of property, plant and equipment and other 11 1 - 1,106 - -

EBITDA 50,293 64,238 70,231 107,683 47,365 53,690

Add: Non-recurring expenses - - 6,318 2,279 3,037 1,778

Less: Equity earnings from unconsolidated affiliates - - - - - (441)

Add: Adjusted earnings from unconsolidated affiliates - - - - - 1,876

Adjusted EBITDA 50,293 64,238 76,549 109,962 50,402 56,903

Less:

Depreciation and accretion expense 13,131 20,829 22,359 33,812 14,386 21,484

Interest expense 8,437 8,519 13,550 27,617 12,825 15,843

Income tax provision (benefit) 253 399 (550) 1,251 551 578

Non-recurring items impacting net income - - 6,318 2,279 3,037 3,213

Net income from continuing operations 28,472$ 34,491$ 34,872$ 45,003$ 19,603$ 15,785$

Six Months EndedYear Ended December 31, June 30,

($ in thousands)

Non-GAAP Reconciliation: 2012 Forecast

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Net income $38 to $43

Add: Depreciation, amortization and accretion expense $45

Add: Interest expense $35

Add: Income tax provision $1

EBITDA $119 to $124

Add: Non-recurring expenses (1) $2

Deduct: Equity earnings from Crestwood Marcellus Midstream ("CMM") ($3)

Add: 35% of CMM's Adjusted EBITDA $7

Adjusted EBITDA $125 to $130

(1) Includes approximately $2 million of non-recurring expenses primarily related to due diligence activitiesof a potential acquisition that is not expected to be completed.

Reconciliation of Net Income to Adjusted EBITDA(in millions)