POWER OF ATTORNEY

KNOW ALL BY THESE PRESENTS, that the undersigned hereby
constitutes and appoints each of James J. Seifert, Michael C. McCormick,
David F. Duvick, and Peter G. Westphal, signing singly,
as the undersigned's true and lawful attorney-in-fact to:

(1)	prepare, execute in the undersigned's name and
on the undersigned's behalf, and submit to the U.S.
Securities and Exchange Commission (the "SEC") a
Form ID, including amendments thereto, and any other
documents necessary or appropriate to obtain codes
and passwords enabling the undersigned to make
electronic filings with the SEC of reports required
by Section 16(a) of the Securities Exchange Act of
1934 or any rule or regulation of the SEC;

(2) 	execute for and on behalf of the undersigned,
in the undersigned's capacity as an officer and/or
director of Ecolab Inc. (the "Company"), Forms 3, 4 and 5
in accordance with Section 16(a) of the Securities
Exchange Act of 1934 and the rules thereunder, and any other
forms or reports the undersigned may be required to file in
connection with the undersigned's ownership, acquisition, or
disposition of securities of the Company;

(3)	do and perform any and all acts for and on behalf
of the undersigned which may be necessary or desirable
to complete and execute any such Form 3, 4 or 5, or other
form or report; complete and execute any amendment or amendments
thereto; and timely file such form or report or amendment with
the SEC and any stock exchange or similar authority; and

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

The undersigned hereby grants to each such attorney-in-fact
full power and authority to do and perform any and every act
and thing whatsoever 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 such attorney-in-fact,
or such attorney-in-fact's substitute or substitutes,
shall lawfully do or cause to be done by virtue of
this power of attorney and the rights and powers
herein granted. The undersigned acknowledges that the
foregoing attorneys-in-fact, in serving in such
capacity at the request of the undersigned, are not
assuming, nor is the Company assuming, any of the
undersigned's responsibilities to comply with Section 16
of the Securities Exchange Act of 1934.

This Power of Attorney shall remain in full force and
effect until the undersigned is no longer required
to file Forms 3, 4 and 5 with respect to the
undersigned's holdings of and transactions in
securities issued by the Company, unless earlier
revoked by the undersigned in a signed writing
delivered to the foregoing attorneys-in-fact.

IN WITNESS WHEREOF, the undersigned has caused this
Power of Attorney to be executed as of this
23rd day of February, 2012.


			    /s/Michael Larson
			    ____________________________________
 		            Michael Larson