Document:

<PAGE>   1
                                                                   Exhibit 10.44

THIS VARIATION OF DEBENTURE is made the 11th day of October 1999.

(A Variation of the Collateral Charge is registered over West Bay Beach North
Block 11D Parcel 8)

BETWEEN:

(1)  CONSOLIDATED WATER CO. LTD., a company incorporated under the laws of the
     Cayman Islands and having its registered office at the offices of
     Consolidated Water Co. Ltd., Trafalgar Place, West Bay Road, P.O. 1114,
     Grand Cayman (hereinafter called "the Borrower") of the ONE PART; and

(2)  ROYAL BANK OF CANADA., a banking corporation licensed to carry on business
     in the Cayman Islands with offices at P.O. Box 245, George Town, Grand
     Cayman (hereinafter called "the Bank") of the OTHER PART,

WHEREAS:

(1)  The Bank and the Borrower entered into a form of Debenture dated the 1st
     day of June 1979 (the "Debenture") to secure the loan of CI$200,000.00
     borrowed from the Bank. A Supplemental Deed was entered into on the 30th
     day of April 1981 for an additional borrowing of CI275,000.00. A second
     Supplemental Deed to the Debenture was entered into on the 10th day of
     March 1983 for an additional borrowing. A third Supplemental Deed to the
     Debenture was entered into on the 6th day of December 1984 for additional
     borrowing. A fourth Supplemental Deed to the Debenture was entered into on
     the 31st day of August 1989;

(2)  The Bank and the Borrower have now agreed to enter into this Variation of
     Debenture to secure a further borrowing from the Bank of US$1,394,000.00 so
     that the total amount of the loan to the borrower shall be US$2,500,000.00;

(3)  The Bank and the Borrower have now agreed that the interest rate shall be
     varied to the Bank's US$ LIBOR plus 1.5%;

(4)  The Bank and the Borrower have now agreed that the repayment of the loan
     shall be revolving

NOW THIS DEED WITNESSES as follows:

1.   Words and terms defined in this Variation of Debenture shall bear the same
     meaning herein as in the Debenture unless expressly provided to the
     contrary.

2.   In consolidation of the said agreement the Borrower and the Bank hereby
     agree the Debenture

[PUBLIC RECORD OFFICE CAYMAN ISLANDS STAMP]
<PAGE>   2
                                       2

     and the Variation of Debenture shall hereafter stand as security for all
     sums owing to the Bank from time to time up to a maximum of
     US$2,500,000.00 (Two Million, Five Hundred Thousand) together with
     interest thereon.

3.   The rate of interest payable shall be the Bank's US$ LIBOR plus 1.5%;

4.   The repayment of the loan by the Borrower shall be revolving;

5.   The Bank hereby consents to the registration of a Variation of Collateral
     Charge over property being held as collateral security to the loan and
     being mentioned in the Schedule to this Variation of Debenture.

6.   All other terms and conditions of the Debenture shall remain in full force
     and effect.

7.   This Variation of Debenture shall be governed by and interpreted in
     accordance with Cayman Islands Law.

IN WITNESS WHEREOF the parties have executed this Variation of Debenture as a
deed the day and year first before written.

                                    SCHEDULE

All that parcel of land on Grand Cayman comprised within Registration Section
West Bay Beach North Block 11D Parcel 8.

THE COMMON SEAL of                 )                /s/ Peter Ribbins
CONSOLIDATED WATER CO. LTD.        )                ------------------------
was hereunto affixed by            )                 Director
and by                             )                /s/ illegible
in the presence of:                )                -------------------------
                                                     Secretary
--------------------------------
Witness

THE COMMON SEAL OF                 )                 ROYAL BANK OF CANADA
ROYAL BANK OF CANADA               )                 GEORGE TOWN, GRAND CAYMAN
was hereunto affixed by            )                 Director
and by                             )
in the presence of:                )                /s/ illegible
                                                     ---------------------------
                                                                         MANAGER
                                                     Asst. Secretary

---------------------------
Witness

                            [PUBLIC RECORDER STAMP]

[PUBLIC RECORD OFFICE CAYMAN ISLANDS STAMP]<PAGE>   1
                                                                   Exhibit 10.45

                                                                      R.12870
                                                                      S.D.$10.00

FORM R.L.9.                      CAYMAN ISLANDS                          2733/79

                         THE REGISTERED LAND LAW, 1971

                                     SECOND
                      COLLATERAL     CHARGE                      [CAYMAN ISLANDS
                                                                 GOVERNMENT
                                                          JUN 2779  STAMP  10.00
                                                                    DUTY

                                                                    TREASURY
                                                                     STAMP]

<TABLE>
<CAPTION>
REGISTRATION  SECTION                   BLOCK                         PARCEL

WEST BAY BEACH NORTH                     11D                             8
---------------------                   -----                         ------
<S>                                    <C>                            <C>
I/WE, CAYMAN WATER COMPANY LIMITED, a Cayman Islands company

  Grand Cayman, Cayman Islands ("the Chargor")
</TABLE>

I, THE REGISTRAR OF LANDS IN THE CAYMAN ISLANDS HEREBY
CERTIFY THAT THIS DOCUMENT WAS RECEIVED BY         FOR
REGISTRATION ON THIS 27 DAY OF JUNE, 1979 AND THAT STAMP DULY
      BY     /TREASURY AT C.I. $10.00 ] LAND REGISTRY       AT C.I. $10.00
    TO HAVE BEEN PAID.

                                                       /s/ [signature illegible]
                                                       -------------------------
                                                          Registrar of Lands

HEREBY CHARGE our interest in the above mentioned title by way of collateral and
additional security to the Debenture ("the Debenture" to which this collateral
charge is supplemental) of even date herewith between the Chargor of the first
part, The Royal Bank of Canada ("the Bank") of the second part, Philip H.
Lustig of the third part and Cayman Public Utilities Ltd., of the fourth part
to secure the payment to the Bank

of P.O. Box 245, Grand Cayman, Cayman Islands

of the principal sum of Two Hundred Thousand Cayman Islands Dollars
(CI$200,000.00) as secured by the Debenture

with interest at the rate of and

payable as provided in the Debenture, subject to section 67 of the above law,
unless negatived, modified or added to by the attached Deed and the debenture.

     The principal sum shall be repaid together with any interest then due, in
accordance with the attached Deed and the Debenture

     And I/WE the above named Chargor hereby acknowledge that we understand the
effect of section 72 of the Registered Land Law, 1971.

          Dated this first day of June 1979

                                                             [REGISTRAR OF LANDS

                                                                CAYMAN ISLANDS

                                                                    SEAL]

[REGISTERED
THIS 3RD DAY OF JULY, 1979

/s/
-------------------------
 REGISTRAR OF LANDS
   CAYMAN ISLANDS

     STAMP]

                                                      [LANDS AND SURVEY REGISTER

                                                               JUL 10 1991

                                                              CAYMAN ISLANDS

                                                                    SEAL]

                          CAYMAN WATER COMPANY LIMITED

Signed by the Chargor   Per: /s/                       - Secretary
                        ------------------------------------------------------

in the presence of:-    Per: /s/                       - Director
                        ------------------------------------------------------

[signature illegible]       THE ROYAL BANK OF CANADA

Signed by the Chargee   Per: /s/                       - Attorney for the Bank
                        ------------------------------------------------------

in the presence of:-

<PAGE>   2
The Registrar of Lands is hereby requested:-

(a)  to register this Charge in favour of the Bank;

(b)  to note on the register that this Charge contains an agreement by the
     Chargor with the Bank that the Chargor will not lease or sub-lease or agree
     to lease or sub-lease or accept surrenders of leases or sub-leases or
     transfer the property the subject of this Charge or any part thereof
     without the written consent of the Bank;

(c)  to note on the register that this Charge gives to the Bank the right to
     consolidate this Charge with any other charge;

(d)  to note on the register that this Charge contains an agreement by the
     Chargor with the Bank that it will not create or purport or attempt to
     create any charge or mortgage which by virtue of any law or regulation will
     rank pari passu with or in priority to this security or second or
     subsidiary to this security without the written consent of the Bank;

(e)  to note on the register that this Charge is a collateral and additional
     security to the Debenture; and

(f)  that this Charge contains an agreement by Philip H. Lustig with the Bank
     whereby the said Philip H. Lustig agrees that the Charge presently
     registered in his name in the encumbrances section of the register relating
     to the above mentioned title shall rank pari passu with this Charge to the
     intent that the Bank shall henceforth rank as pari passu First Chargee with
     the said Philip H. Lustig.

[Public Record Office Cayman Islands Stamp]
[Registrar of Lands Cayman Islands Stamp]

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00010-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00010-of-00352.parquet"}]]