POWER OF ATTORNEY
                       For Executing Forms 3, FORMS 4 and
                   FORMS 5, Form 144 and Schedule 13D and 13G

The undersigned hereby constitutes and appoints Laura L. Ozenberger, Michael K.
Post and Judy R. Riddle, or any of them acting without the others, with full
power of substitution, as the undersigned's true and lawful attorney-in-fact to:

     1.   Execute for and on behalf of the undersigned (a) any Form 3, Form 4
          and Form 5 (including amendments thereto) in accordance with Section
          16(a) of the Securities Exchange Act of 1934, as amended (the
          "Exchange Act"), (b) Form 144 and (c) Schedule 13D and Schedule 13G
          (including amendments thereto) in accordance with Sections 13(d) and
          13(g) of the Exchange Act, but only to the extent each form or
          schedule relates to the undersigned's beneficial ownership of
          securities of Inergy Midstream, L.P. or any of its subsidiaries;

     2.   Do and perform any and all acts for and on behalf of the undersigned
          that may be necessary or desirable to complete and execute any Form 3,
          Form 4, Form 5, Form 144, Schedule 13D or Schedule 13G (including
          amendments thereto) and timely file the forms or schedules with the
          Securities and Exchange Commission and any stock exchange or quotation
          system, self-regulatory association or any other authority, and
          provide a copy as required by law or advisable to such persons as the
          attorney-in-fact deems appropriate; and

     3.   Take any other action in connection with the foregoing that, in the
          opinion of the attorney-in-fact, may be of benefit to, in the best
          interest of or legally required of the undersigned, it being
          understood that the documents executed by the attorney-in-fact on
          behalf of the undersigned pursuant to this Power of Attorney shall be
          in the form and shall contain the terms and conditions as the
          attorney-in-fact may approve in the attorney-in-fact's discretion.

The undersigned hereby grants to the attorney-in-fact full power and authority
to do and perform all and every act requisite, necessary or proper to be done in
the exercise of any of the rights and powers herein granted, as fully to all
intents and purposes as the undersigned might or could do if personally present,
with full power of substitution or revocation, hereby ratifying and confirming
all that the attorney-in-fact shall lawfully do or cause to be done by virtue of
this Power of Attorney and the rights and powers granted herein. The undersigned
acknowledges that the attorneys-in-fact, in serving in such capacity at the
request of the undersigned, are not assuming (nor is Inergy Midstream, L.P.
assuming) any of the undersigned's responsibilities to comply with Section 16 of
the Exchange Act.

The undersigned agrees that the attorney-in-fact may rely entirely on
information furnished orally or in writing by or at the direction of the
undersigned to the attorney-in-fact. The undersigned also agrees to indemnify
and hold harmless Inergy Midstream, L.P. and the attorney-in-fact against any
losses, claims, damages or liabilities (or actions in these respects) that arise
out of or are based upon any untrue statements or omissions of necessary facts
in the information provided by or at the direction of the undersigned, or upon
the lack of timeliness in the delivery of information by or at the direction of
the undersigned, to the attorney-in fact for purposes of executing,
acknowledging, delivering or filing a Form 3, Form 4, Form 5, Form 144, Schedule
13D or Schedule 13G (including amendments thereto) and agrees to reimburse
Inergy Midstream, L.P. and the attorney-in-fact on demand for any legal or other
expenses reasonably incurred in connection with investigating or defending
against any such loss, claim, damage, liability or action.

This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file Form 3, Form 4, Form 5, Form 144,
Schedule 13D and Schedule 13G (including amendments thereto) with respect to the
undersigned's holdings of and transactions in securities issued by Inergy
Midstream, L.P., unless earlier revoked by the undersigned in a signed writing
delivered to the attorney-in-fact. This Power of Attorney does not revoke any
other power of attorney that the undersigned has previously granted.

IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of the date written below.

/s/ John J. Sherman
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Signature

John J. Sherman
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Type or Print Name

December 8, 2011
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Date