Exhibit 10.21

CONSULTING AGREEMENT

THIS CONSULTING AGREEMENT (this “Agreement”) is made and entered into effective
as of the 1st day of November, 2011 (the “Effective Date”), by and between
PIEDMONT NATURAL GAS COMPANY, INC. a North Carolina corporation (“Piedmont”),
and DAVID J. DZURICKY (“Consultant”).

W I T N E S S E T H:

WHEREAS, Consultant was employed for many years by Piedmont, most recently in
the position of Chief Financial Officer, and his employment ended effective as
of October 31, 2011; and

WHEREAS, Consultant possesses valuable skills and experience of a special and
personal nature, and unique, personal and confidential business knowledge about
the operation of Piedmont’s business; and

WHEREAS, Piedmont desires to secure for itself the benefit of Consultant’s
ability and expertise; and

WHEREAS, Consultant has indicated his willingness to provide consulting and
advisory services to Piedmont on the terms and conditions set forth herein.

NOW, THEREFORE, in consideration of the foregoing, the parties hereto agree as
follows:

1. Engagement. Piedmont hereby engages Consultant, as an independent contractor,
to provide the consulting services more particularly described herein, and
Consultant accepts such engagement, subject to the terms and conditions stated
herein.

2. Consulting Services. Consultant shall be available, at reasonable times after
reasonable notice, to provide advisory and consulting services to Piedmont’s
finance, accounting, rates and regulatory groups, including providing assistance
with (i) the preparation and filing of Piedmont’s annual report on SEC Form 10-K
for the fiscal year ended October 31, 2011, (ii) the rate case currently pending
for Piedmont’s service territory in Tennessee, (iii) strategic planning and
review of joint venture opportunities and (iv) providing transition assistance
to Piedmont’s newly appointed Chief Financial Officer. During the term of this
Agreement, Consultant shall devote such time and attention to the business of
Piedmont as is necessary to fulfill his duties and responsibilities under this
Agreement, but in no event shall he be required to devote, on average, more than
20% of his time during the term of this Agreement to his duties hereunder.

3. Term. This Agreement shall be effective as of the Effective Date and shall
continue in effect until October 31, 2012 unless terminated earlier in
accordance with Section 11.

4. Compensation. For the services provided by Consultant as an independent
contractor of Piedmont, Piedmont shall pay Consultant a consulting fee (the
“Consulting Fee”) in the amount of Two Hundred Forty Thousand Dollars
($240,000). The Consulting Fee shall be payable in monthly installments.

5. Business Expenses. Piedmont shall pay or reimburse Consultant for all
reasonable bona fide business expenses incurred by Consultant in the performance
of services under this Agreement in accordance with expense reimbursement plans
consistent with current policies in effect for consultants to Piedmont
generally.

--------------------------------------------------------------------------------

6. Indemnification. Piedmont shall indemnify Consultant (and advance expenses in
the event of a claim for indemnification) with respect to any claim, loss or
proceeding arising out of or relating to the performance of his services as a
Consultant or his serving in such capacity, to the same extent as the directors
and executive officers of Piedmont.

7. Relationship of Parties. Consultant is acting under this Agreement as an
independent contractor of Piedmont and not as an employee. As such, Consultant
shall have no claim against the Company for vacation pay, sick leave, retirement
benefits, Social Security, workers compensation, health or disability benefits,
unemployment insurance benefits or employee benefits of any kind based on
services performed during the term of this Agreement. Moreover, Consultant shall
have no claim for compensation, remuneration, reimbursement, or other monies
except as expressly set forth in this Agreement.

8. Tax Matters. Under this Agreement, Consultant is an independent contractor of
Piedmont. Accordingly, Piedmont is not required to, and shall not, withhold any
income or employment taxes from the Consulting Fee. Consultant shall pay all
income and employment taxes with respect to the Consulting Fee and other
payments made hereunder.

9. Non-Competition. Consultant acknowledges that (i) Piedmont is an energy
services company primarily engaged in the distribution of natural gas to
residential, commercial, industrial and power generation utility customers;
(ii) Consultant is one of a limited number of persons who has unique knowledge
of, and expertise and experience in, the business; (iii) the business is
conducted in the States of North Carolina, South Carolina and Tennessee ;
(iv) Piedmont also has joint venture investments in businesses operating in the
states of North Carolina, Georgia and West Virginia, among others (the areas
covered by (iii) and (iv) called the “Restricted Territory”); (v) his experience
with Piedmont and its subsidiaries have given him possession of and access to
trade secrets of, and Confidential Information (as defined in Section 10 below)
and, following the date of this Agreement, Consultant will continue to have
access to additional trade secrets and strategic and Confidential Information;
and (vi) the agreements and covenants contained in this Section 9 and in
Section 10 are essential to protect the business, the trade secrets, the
Confidential Information and the goodwill of Piedmont and its subsidiaries.

Accordingly, Consultant agrees that he will not, during the term of this
Agreement and for a period of eighteen (18) months thereafter (the “Restricted
Period”) within the Restricted Territory, directly or indirectly, for any
reason, for his own account or on behalf of or together with any other entity:

 

  (i) own or have any interest in or act as an officer, director, partner,
principal, employee, agent, representative, consultant or independent contractor
of, or in any way assist in, any business that competes with any business
engaged in by Piedmont or any of its subsidiaries during the term of this
Agreement (the “Competitive Businesses”); it being understood and agreed that
this clause shall not be violated by Consultant’s passive equity interest of
less than five percent (5%) in an entity engaged in a Competitive Business whose
shares are listed on a securities exchange or regularly quoted in the
over-the-counter market;

 

2

--------------------------------------------------------------------------------

  (ii) solicit clients, customers, or accounts of Piedmont or its subsidiaries
for, on behalf of or otherwise related to any such Competitive Businesses or any
services or products related thereto;

 

  (iii) hire, solicit or in any manner encourage any person who is in the employ
or service of Piedmont or its subsidiaries to leave or terminate such
relationship for any other employment opportunity; or

 

  (iv) advise any investors or potential investors making or considering
acquisitions of entities engaged in Competitive Businesses.

10. Confidential Information. For purposes of this Agreement, “Confidential
Information” means information which is used in the business of Piedmont or its
subsidiaries and (i) is proprietary to, about or created by Piedmont or its
subsidiaries, (ii) gives Piedmont or its subsidiaries some competitive business
advantage or the opportunity of obtaining such advantage or the disclosure of
which could be detrimental to the interests of Piedmont or its subsidiaries,
(iii) is reasonably designated as Confidential Information by Piedmont or its
subsidiaries, is known by Consultant to be considered confidential by Piedmont
or its subsidiaries, or from all the relevant circumstances should reasonably be
assumed by Consultant to be confidential and proprietary to Piedmont or its
subsidiaries, or (iv) is not generally known to personnel not associated with
Piedmont or its subsidiaries.

Consultant hereby acknowledges, understands and agrees that all Confidential
Information is the exclusive and confidential property of Piedmont or its
subsidiaries which shall at all times be regarded, treated and protected as
such. Consultant further acknowledges that all such Confidential Information is
a trade secret.

11. Termination. This Agreement may be terminated as follows:

(a) This Agreement may be terminated effective immediately by Piedmont for Cause
by giving written notice of termination to Consultant, which notice shall
specify the reason for termination. For purposes of this Agreement, “Cause”
shall mean that Consultant has (i) committed an act of material dishonesty,
fraud, embezzlement, or breach of trust against Piedmont or an act which he knew
to be in violation of his duties to Piedmont (including the unauthorized
disclosure of Confidential Information); (ii)directly or indirectly made or
published any disparaging comments to other parties about Piedmont, its
subsidiaries, business or prospects or any of its executive officers or
directors (and specifically including but not limited to parties with a business
relationship with Piedmont); (iii) violated any of the agreements and covenants
contained in Sections 9 and 10; or (iv) committed a material breach of this
Agreement, if such breach is not remedied within ten (10) days after written
notice thereof by Piedmont. After the effective date of termination under this
Section 11, Piedmont shall have no further obligations under this Agreement,
except to pay the accrued but unpaid Consulting Fee up to and as of such
effective date.

 

3

--------------------------------------------------------------------------------

(b) This Agreement shall terminate upon the death of Consultant. In the event
that this Agreement terminates due to Consultant’s death, Piedmont shall pay
upon such termination to Consultant’s estate the accrued but unpaid Consulting
Fee up to and as of the date of Consultant’s death.

12. Code of Business Conduct and Ethics. Consultant hereby acknowledges,
understands and agrees that all work performed for Piedmont under this contract
shall comply with Piedmont’s Code of Business Conduct and Ethics, available on
Piedmont’s website at www.piedmontng.com. Consultant also acknowledges,
understands and agrees that all work performed for Piedmont under this Contract
must comply with all applicable laws and regulations.

13. Entire Agreement. This Agreement constitutes the entire agreement between
the parties and supersedes any prior communications, agreements and
understandings, written or oral, with respect to the terms and conditions of
Consultant’s service with Piedmont.

14. Amendment. This Agreement may be amended or modified only by a written
instrument signed by Consultant and by a duly authorized representative of
Piedmont.

15. Governing Law. This Agreement, and any issue, claim or proceeding arising
out of or relating to this Agreement or the conduct of the parties hereto, shall
be governed by and construed in accordance with the laws of the State of North
Carolina without regard to conflicts or choice of law principles which would
cause the application of the domestic substantive laws of any jurisdiction other
than North Carolina.

16. Counterparts. This Agreement may be executed in two or more counterparts,
each of which shall be deemed an original, but all of which together shall
constitute one and the same instrument.

17. Assignment. No party shall have any right to assign, mortgage, pledge,
hypothecate or encumber this Agreement in whole or in part, or any benefit or
any right accruing hereunder, without in any such case first obtaining the prior
written consent of the other party hereto.

18. Notices. Any notices, requests, demands and other communications provided
for by this Agreement shall be in writing and shall be deemed to be effectively
given (i) upon confirmation of facsimile, (ii) one business day after being sent
by overnight delivery and (iii) three business days after being mailed by United
States registered or certified mail, return receipt requested and postage
prepaid at the following addresses:

to Piedmont:

Piedmont Natural Gas Company, Inc.

4720 Piedmont Row Drive

Charlotte, North Carolina 28210

Attention: Kevin O’Hara, Senior Vice President and

Chief Administrative Officer

 

4

--------------------------------------------------------------------------------

with a copy to:

Piedmont Natural Gas Company, Inc.

4720 Piedmont Row Drive

Charlotte, North Carolina 28210

Attention: Jane Lewis-Raymond, Senior Vice President — General Counsel,

Corporate Secretary and Chief Compliance and Community Affairs Officer

If to Consultant, notice shall be sent to the most recent address on Piedmont’s
records for Consultant.

19. Miscellaneous. Any protection, benefits, rights or other provisions given to
Piedmont in this Agreement shall also be deemed to apply to, protect and inure
to the benefit of Piedmont’s affiliates and subsidiaries. All rights of Piedmont
expressed in this Agreement are in addition to any rights available under the
common law or other legal principles. Section or paragraph titles or captions
contained in this Agreement are inserted only as a matter of convenience and for
reference and in no way define, limit, extend or describe the scope of this
Agreement or the intent of any provision hereof. All pronouns and any variation
thereof shall be deemed to refer to the masculine, feminine, neuter, singular or
plural as the identity of person or persons, firm or firms, corporation or
corporations, and as context may require.

[Signatures on following page]

 

5

--------------------------------------------------------------------------------

IN WITNESS WHEREOF, Piedmont has caused this Agreement to be executed by a duly
authorized officer and Consultant has hereunto set his hand, all as of the day
and year first above written.

 

CONSULTANT /s/ David J. Duricky David J. Dzuricky

 

PIEDMONT NATURAL GAS COMPANY, INC. By:   /s/ Kevin M. O’Hara Name:   Kevin M.
O’Hara Title:   Senior Vice President and   Chief Administrative Officer

 

6