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.

ISE Clean Edge Water Index Components (Last updated March 2018)

Ticker Name
WMS Advanced Drainage Systems Inc
ACM Aecom
AEGN Aegion Corp
A Agilent Technologies Inc
AWR American States Water Co
AWK American Water Works Company Inc
AOS AO Smith
WAAS AquaVenture Holdings Limited
WTR Aqua America Inc
BMI Badger Meter Inc
CWT California Water Service Group
SBS Companhia de Saneamento Basico
DHR Danaher Corporation
ECL Ecolab Inc
ERII Energy Recovery Inc.
AQUA Evoqua Water Technologies
FLS Flowserve Corp
FRTA Forterra Inc 
Ticker Name
FELE Franklin Electric Co
GRC Gorman-Rupp Co
IEX IDEX Corporation
IDXX IDEXX Laboratories Inc
ITRI Itron Inc
LNN Lindsay Corporation
MSEX Middlesex Water
MLI Mueller Industries Inc
MWA Mueller Water Products Inc
PNR Pentair
RXN Rexnord Corp
ROP Roper Technologies Inc
TTEK Tetra Tech, Inc.
VMI Valmont Industries Inc
WTS Watts Water Technologies Inc
XYL Xylem Inc
YORW York Water Co

ISE Clean Edge Water Index Semi-Annual Changes

As a result of the September 2018 evaluation and intra-quarterly updates, the following securities were most recently added or removed from the Index:    

Addition: AquaVenture Holdings Limited (NYSE: WAAS).

Removal: Connecticut Water Service, Inc. (NASDAQ: CTWS).

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), holding companies, 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 or NYSE MKT; 
  • 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.

For detailed methodology information visit here .

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, and nothing contained herein should be construed as investment advice, either on behalf of a particular financial product or an overall investment strategy. Clean Edge, Inc., does not make any recommendation to buy or sell any financial product or any representation about the financial condition of any company or fund.