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                                                                   Exhibit 10.17

                                22 December 2004

                               BALFOUR BEATTY PLC

                                       and

                     MACQUARIE INFRASTRUCTURE (UK) LIMITED

                                       and

                             CONNECT M1-A1 LIMITED

                                       and

                          MACQUARIE YORKSHIRE LIMITED

                                       and

                      MACQUARIE INFRASTRUCTURE COMPANY LLC


              DEED OF NOVATION RELATING TO THE SECONDMENT AGREEMENT

Linklaters

One Silk Street
London EC2Y 8HQ

Telephone (44-20) 7456 2000
Facsimile (44-20) 7456 2222

Ref Alexander Currie
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THIS DEED is made on 22 December 2004 BETWEEN:

(1)  BALFOUR BEATTY PLC (registered number 395826) whose registered office is at
     130 Wilton Road, London, SW1V 1LQ (formerly BICC PLC) ("BB");

(2)  MACQUARIE INFRASTRUCTURE (UK) LIMITED (registered number 1540913) whose
     registered office is at Level 29 and 30, 1 Ropemaker Street, London EC2Y
     9HD (formerly Trafalgar House Corporate Development Limited) ("MIUK");

(3)  CONNECT M1-A1 LIMITED (registered number 2999303) whose registered office
     is at 7th Floor, Saddlers House, Gutter Lane, London EC2V 6HS (formerly
     Yorkshire Link Limited) ("CONNECT"); and

(4)  MACQUARIE YORKSHIRE LIMITED (registered number 4712996) whose registered
     office is at Level 29 and 30, 1 Ropemaker Street, London EC2Y 9HD ("MYL");

(5)  MACQUARIE INFRASTRUCTURE COMPANY LLC whose principal executive office is at
     600 Fifth avenue, 21st floor, 10020 NY, USA (formerly Macquarie
     Infrastructure Assets LLC) ("MICL" or the "Guarantor").

WHEREAS:

(A)  BB, MIUK and Connect have entered into the Secondment Agreement (as defined
     in this Deed).

(B)  Pursuant to a share purchase agreement entered into between Macquarie
     European Infrastructure PLC ("MEIP") and MICL on or around the date hereof,
     MEIP will sell and MICL will purchase the 5,000,000 ordinary shares owned
     by MEIP in MYL.

(C)  MIUK therefore wishes to be released and discharged from the Secondment
     Agreement and the parties have agreed to the novation of the Secondment
     Agreement from MIUK to MYL.

(D)  The Guarantor agrees to guarantee to MIUK and Connect the obligations of
     MYL under or pursuant to this Deed and the Replacement Secondment Agreement
     (as defined in this Deed).

(E)  The Guarantor and BB have separately entered into a guarantee on or around
     the date hereof pursuant to which the Guarantor agrees to guarantee to BB,
     inter alia, the performance by MYL of its obligations under or pursuant to
     this Deed.

(F)  Yorkshire Link Limited changed its name to Connect M1-A1 Limited on 2 June
     2004.

IT IS AGREED

1    DEFINITIONS AND INTERPRETATION

     In this Deed the following expressions shall have the following meanings:

     "Continuing Parties": means BB and Connect;

     "Effective Date": means the date of this Deed;

     "Replacement Secondment Agreement": means the agreement to replace the
     Secondment Agreement as set out in Clause 2.1; and

     "Secondment Agreement": means the secondment agreement dated 26 March 1996
     as amended and restated on 30 April 2003, between BB, Connect and MIUK.


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2    NOVATION

     With effect from the Effective Date:

     2.1  The Secondment Agreement shall be terminated and the Secondment
          Agreement shall be replaced by the Replacement Secondment Agreement,
          which shall be on identical terms to the Secondment Agreement save
          that:

          2.1.1 MYL shall be a party in place of MIUK;

          2.1.2 references to "Macquarie Infrastructure (UK) Limited (registered
                number 1540913) of Level 29 and 30, 1 Ropemaker Street, London
                EC2Y 9HD" shall be references to "Macquarie Yorkshire Limited
                (registered number 4712996) of Level 29 and 30, 1 Ropemaker
                Street, London EC2Y 9HD";

          2.1.3 from Recital (f) onwards references to "MIUK" shall be
                references to "MYL";

          2.1.4 from Clause 1 onwards references to "Macquarie European
                Infrastructure plc" shall be references to "Macquarie
                Infrastructure Company LLC"; and

          2.1.5 from Clause 1 onwards references to "MEIP" shall be references
                to "MICL".

          2.1.6 from Clause 1 onwards references to "YLL" shall be references to
                "Connect".

          2.1.7 references to "Yorkshire Link Limited of (registered number
                2999303) whose registered office is at Level 29 and 30, 1
                Ropemaker Street, London EC2Y 9HD" shall be references to
                "Connect M1-A1 Limited of (registered number 2999303) whose
                registered office is at Level 29 and 30, 1 Ropemaker Street,
                London EC2Y 9HD".

     2.2  MYL undertakes with the Continuing Parties, from the Effective Date,
          to accept, observe, perform, discharge and be bound by the Replacement
          Secondment Agreement.

     2.3  Notwithstanding the undertaking provided in Clause 2.2, nothing in
          this Deed shall:

          2.3.1 require MYL to perform any obligation created by or arising
                under the Secondment Agreement falling due for performance, or
                which should have been performed by MIUK, before the Effective
                Date; or

          2.3.2 make MYL liable for any act, neglect, default or omission in
                respect of the Secondment Agreement committed by MIUK occurring
                before the Effective Date.

     2.4  With effect from the Effective Date, the Continuing Parties agree to
          the substitution of the Replacement Secondment Agreement in place of
          the Secondment Agreement and accept MYL's undertaking in Clause 2.2
          above to observe, perform, discharge and be bound by the Replacement
          Secondment Agreement.

     2.5  The Continuing Parties hereby release and discharge MIUK from all
          claims and demands from each of the Continuing Parties, and from each
          of its liabilities and obligations, howsoever arising under the
          Secondment Agreement to the extent assumed by MYL pursuant to this
          Deed and accept the like liabilities and obligations to them of MYL in
          place of MIUK under the Replacement Secondment Agreement.

     2.6  Notwithstanding Clause 2.5, nothing in this Deed shall affect or
          prejudice any claim or demand whatsoever which the Continuing Parties
          may have against MIUK in


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          relation to the Secondment Agreement and arising out of matters prior
          to the Effective Date.

     2.7  With effect from the Effective Date, MIUK hereby releases and
          discharges the Continuing Parties from all claims and demands by MIUK,
          and from each of their respective liabilities and obligations to MIUK,
          howsoever arising under the Secondment Agreement. Notwithstanding this
          undertaking and release, nothing in this Deed shall affect or
          prejudice any claim or demand whatsoever which MIUK may have against
          the Continuing Parties in relation to the Secondment Agreement and
          arising out of matters prior to the Effective Date.

3    INDEMNITY

     MIUK hereby undertakes to indemnify MYL in respect of all liabilities,
     losses, charges, costs, claims or demands incurred or made by MYL in
     relation to the Secondment Agreement and arising from acts or omissions of
     MIUK prior to the Effective Date.

4    GUARANTEE

     4.1  The Guarantor unconditionally and irrevocably guarantees to MIUK and
          Connect the due and punctual performance and observance by MYL of its
          obligations, commitments, undertakings, warranties and indemnities
          under or for breach of this Deed and the Replacement Secondment
          Agreement (the "Guaranteed Obligations").

     4.2  If and whenever MYL defaults for any reason whatsoever in the
          performance of any of the Guaranteed Obligations, the Guarantor shall
          forthwith upon demand unconditionally perform (or procure performance
          of) and satisfy (or procure satisfaction of) the Guaranteed
          Obligations in respect of which there has been default in the manner
          prescribed by this Deed and so that the same benefits shall be
          conferred on MIUK and Connect as they would have received if the
          Guaranteed Obligations had been duly performed and satisfied by MYL.

     4.3  This guarantee is a continuing guarantee and is to remain in force
          until all the Guaranteed Obligations have been performed or satisfied.
          This guarantee is in addition to and without prejudice to and not in
          substitution for any rights or security which MIUK and Connect may now
          or hereafter have or hold for the performance and observance of the
          Guaranteed Obligations.

     4.4  The liability of the Guarantor under this Clause 4 shall not be
          released or diminished by any variation of the Guaranteed Obligations
          or any forbearance, neglect or delay in seeking performance of the
          Guaranteed Obligations or any granting of time for such performance
          and shall not be affected or impaired by reason of any other fact or
          event which in the absence of this provision would or might constitute
          or afford a legal or equitable discharge or release or a defence to a
          guarantor.

5    FURTHER ASSURANCE

     Each of the parties agrees to perform (or procure the performance of) all
     further acts and things, and execute and deliver (or procure the execution
     and delivery of) such further documents, as may be required by law or as
     may be necessary or reasonably desirable to implement and/or give effect to
     this Deed.


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6    COUNTERPARTS

     This Deed may be executed in any number of counterparts and by the parties
     to it on separate counterparts, each of which is an original but all of
     which together constitute one and the same instrument.

7    NO RIGHTS UNDER CONTRACTS (RIGHTS OF THIRD PARTIES) ACT 1999

     A person who is not a party to this Deed shall have no right under the
     Contracts (Rights of Third Parties) Act 1999 to enforce any of the terms of
     this Deed or the Replacement Secondment Agreement.

8    GOVERNING LAW

     8.1  This Deed and the relationship between the parties shall be governed
          by, and interpreted in accordance with English law.

     8.2  All parties agree that the Courts of England are to have exclusive
          jurisdiction to settle any dispute (including claims for set-off and
          counterclaim) which may arise in connection with the creation,
          validity, effect, interpretation or performance of, or the legal
          relationships established by this Deed or otherwise arising in
          connection with this Deed or the Replacement Secondment Agreement and
          for such purposes irrevocably submit to the jurisdiction of the
          English Courts.

     8.3  MICL shall at all times maintain an agent for service of process and
          any other documents in proceedings in England or any other proceedings
          in connection with this Deed or the Replacement Secondment Agreement.
          Such agent shall be MYL of Level 29 and 30, 1 Ropemaker Street, London
          EC2Y 9HD and any judgment or other notice of legal process shall be
          sufficiently served on MICL if delivered to such agent at its address
          for the time being. MICL agrees to inform each party in writing of any
          change of address of such process agent within 28 days of such change.
          If such process agent ceases to be able to act as such or to have an
          address in England, MICL irrevocably agrees to appoint a new process
          agent in England and to deliver to each party within 14 days a copy of
          a written acceptance of appointment by the process agent.

AS WITNESS this Deed has been executed by the parties hereto and is hereby
delivered on the date first above written.


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EXECUTED and DELIVERED
as a DEED on behalf of
BALFOUR BEATTY PLC by

/s/ A. L. P. Rabin
-------------------------------------
Name: A. L. P. Rabin
      Director


/s/ C.R. O'N Pearson
-------------------------------------
Name: C.R. O'N Pearson
      Director / Secretary

EXECUTED and DELIVERED
as a DEED on behalf of
MACQUARIE INFRASTRUCTURE
(UK) LIMITED by


/s/ DAVID HARRISON
-------------------------------------
Name: DAVID HARRISON
      Director


/s/ ANNABELLE HELPS
-------------------------------------
Name: ANNABELLE HELPS
      Secretary


EXECUTED and DELIVERED
as a DEED on behalf of
CONNECT M1-A1 LIMITED by


/s/ DAVID HARRISON
-------------------------------------
Name: DAVID HARRISON
      Director


/s/ Ian Rylatt
-------------------------------------
Name: Ian Rylatt
      Director / Secretary


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EXECUTED and DELIVERED
as a DEED on behalf of
MACQUARIE YORKSHIRE
LIMITED by


/s/ Peter Antolik
-------------------------------------
Name: Peter Antolik
      Director


/s/ Annabelle Helps
-------------------------------------
Name: Annabelle Helps
      Secretary


EXECUTED and DELIVERED
as a DEED on behalf of
MACQUARIE INFRASTRUCTURE
COMPANY LLC by


/s/ Peter Stokes
-------------------------------------
Name(s): Peter Stokes

Authorised Signatory /
Signatories


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