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ISE Clean Edge Water Index (HHO)

HHO Index Logo

The ISE Clean Edge Water Index (HHO) is a modified market capitalization-weighted index designed to track the performance of companies that derive a substantial portion of their revenues from the potable water and wastewater industry. Industry exposure includes water distribution, infrastructure (pumps, pipes, and valves), water solutions (purification and filtration), and ancillary services such as consulting, construction, and metering.

An  exchange traded fund, FIW , is based on the ISE Clean Edge Water Index and is sponsored by First Trust Advisors L.P. See index components and learn more about our methodologies, up-to-date performance, and licensed products below.

facts Click above to access the ISE Clean Edge Water Index (HHO) Fact Sheet.

ISE Clean Edge Water Index Components (Last updated September 2023)

WMSAdvanced Drainage Systems Inc
AAgilent Technologies Inc
AQNAlgonquin Power & Utilities Corp
AWRAmerican States Water Co
AWKAmerican Water Works Company Inc
BMIBadger Meter Inc
CWTCalifornia Water Service Group
SBSCompanhia de Saneamento Basico
CNMCore & Main, Inc.
DHRDanaher Corporation
ECLEcolab Inc
ERIIEnergy Recovery Inc
WTRGEssential Utilities, Inc
FERGFerguson Plc 
FLSFlowserve Corp
FELEFranklin Electric Co
IEXIDEX Corporation
IDXXIDEXX Laboratories Inc
ITRIItron Inc
LNNLindsay Corporation
MSEXMiddlesex Water
MLIMueller Industries Inc
MWAMueller Water Products Inc
PRMWPrimo Water Corp
ROPRoper Technologies Inc
STNStantec, Inc.
TTEKTetra Tech, Inc.
VMIValmont Industries Inc
WATWaters Corp.
WTSWatts Water Technologies Inc
XYLXylem Inc
ZWSZurn Water Solutions Corp

constituents Click above to access an overview of all HHO Index constituents.

ISE Clean Edge Water Index Semi-Annual Changes

As a result of the September 2023 evaluation and/or intraquarterly changes, the following securities were most recently added or removed from the index: 

Additions: Ferguson Plc (New York: FERG) and Waters Corp. (New York: WAT)

Deletions: Hawkins, Inc. (NASDAQ: HWKN) and Montrose Environmental Group, Inc. (New York: MEG)

Historical changes are available here .

ISE Clean Edge Water Index Performance

Historical index performance is available here .

ISE Clean Edge Water Index Methodologies

Index Calculation

The ISE Clean Edge Water Index (HHO) (formally the ISE Water Index) began on December 29, 2000 at a base value of 28.80.  Click here  to learn more.


Index eligibility is limited to specific security types only.  The security type eligible for the Index include common stocks, ordinary shares, and depositary receipts. Security types not eligible for the index include closed-end funds, exchange-traded funds (ETF), investment vehicles or Real Estate Investment Trusts (REIT).

Eligibility Criteria

To be eligible for inclusion in the Index, a security must meet the following criteria:

  • the issuer of the security must derive a substantial portion of their revenues from the potable and wastewater industry, according to Clean Edge;
  • be listed on The Nasdaq Stock Market, the New York Stock Exchange, NYSE American, or the CBOE Exchange; 
  • a minimum worldwide market capitalization of $100 million;
  • a minimum free float of 20%;
  • a minimum three-month average daily dollar trading volume (ADDTV) of $500 thousand;
  • one security per issuer is permitted;
  • have “seasoned” for at least three months on an index recognized market;
  • the issuer of the security may not have entered into a definitive agreement or other arrangement which would likely result in the security no longer being Index eligible; 
  • may not be issued by an issuer currently in bankruptcy proceedings; and
  • the issuer of the security may not have annual financial statements with an audit opinion that is currently withdrawn.

methodology Click above to access detailed HHO index methodology information.

Financial Products Based on the ISE Clean Edge Water Index

The First Trust Water ETF (FIW) is based on the ISE Clean Edge  Water Index (HHO) and is sponsored by First Trust Advisors L.P.

The information contained above is provided for informational and educational purposes only. Clean Edge is not an investment adviser, and none of the information, including any Nasdaq Clean Edge index, should be construed as investment advice or relied on as the basis for making any kind of investment decision. Neither Clean Edge nor any of its affiliates makes any recommendation whatsoever to buy or sell any securities, fund, or financial product or any representation about the financial condition of any company, fund, or financial product. Information regarding any Clean Edge index is not a guarantee of future performance. Actual results may differ materially from those expressed or implied. Past performance is not indicative of future results and should never be relied upon for making any kind of investment decisions. Investors should undertake their own due diligence and carefully evaluate companies before investing. ADVICE FROM A SECURITIES PROFESSIONAL IS STRONGLY ADVISED.