Marsh destruction: Green Coalition questions CDPQ Infra

Letter seeks answers about the draining of l’Étang aux hérons

Montreal, September 7, 2021

The Green Coalition announces today that it has sent a letter to CDPQ Infra asking for the answers to pressing concerns about the draining of Étang aux hérons by the REM tunnelling operations under the Technoparc wetlands. This environmental disaster has become even more alarming with the discovery of a new second large adjacent sinkhole.

The Green Coalition calls on CDPQ Infra to assume responsibility for this environmental catastrophe and to be totally transparent on the subject with the public.

The letter below requires that CDPQ Infra immediately release answers to seven pertinent questions to the public.

Jean-Marc Arbaud
President and Chief Executive Officer
CDPQ Infra
and
Jean-Vincent Lacroix
Director of Communications

Édifice Jacques-Parizeau
1000, place Jean-Paul Riopelle
Montréal (Québec) H2Z 2B3

September 6, 2021

RE: Destruction of l’Étang aux hérons

Dear Sirs,

The Green Coalition is writing to you to request clarification of a number of points raised by you in the media and on your website. Here are the questions:

1. Cause of the loss of water and subsidence under the Étang aux hérons, and the new, second sinkhole just discovered adjacent to it:

As you have stated, there has been a catastrophic loss of water coupled with ground subsidence under the Étang aux hérons. This site, whose integrity is of great concern to the public, lies immediately above your ongoing tunnelling operation.

Question: You have not admitted that your tunnelling caused the drainage and subsidence. To what, then, do you attribute these problems?

2. Public transparency:

You have claimed that, upon informing the Ministère de l’Environnement et la Lutte Contre les Changements Climatiques and the City of Montréal, you performed “appropriate analyses” to determine the reasons for the loss of water in the preceding few weeks. Although the public has the right to know, you have not disclosed the results of your analysis.

Question: Will you please immediately make public the results of your analysis of the drainage and subsidence?

3. Your statement that only snow and rainwater are sources for the water in the Étang aux hérons:

We are particularly concerned by your claim that the marsh is fed only by precipitation, and that it has dried up because of dry weather. This claim needs to be substantiated, given that: (1) photos show that it has not dried up in previous summers; and (2) there is at least one surface waterway feeding into the marsh at various times of the year.

Question: Will you please immediately make public the proof of your claim that the marsh gets its water exclusively from precipitation?

4. The real effects of your tunnelling operation:

Past observations of the Étang aux hérons make it clear that the current drying and subsidence is unique, while this damage coincides precisely with your tunnelling operation.

Question: Will you please immediately make public the evidence you have that your tunnelling did not cause the damage to the marsh?

5. The source of water being used to rehydrate the marsh:

Any attempt to rehydrate the marsh using water from Montreal’s water mains raises very serious environmental concerns. Chlorinated water from the mains will damage the flora and fauna essential to the food web, including at the micro level. Chlorinated water also has deleterious consequences for the resident fish and invertebrates, as well as the waterfowl that feed on them.

Question: Will you please immediately confirm publicly that you will not rehydrate the marsh with chlorinated water?

6. Liquid Nitrogen:

Through a seven-month period, truck loads of liquid nitrogen were delivered to Étang aux hérons. The liquid nitrogen was continuously used to stabilize soils so that the tunnelling could proceed, we understood.

Question: Will the use of liquid nitrogen be a permanent solution to unstable soils surrounding the tunnel into the future – how long a future? What are the environmental impacts of such a solution?

7. The fish:

Coinciding with the appearance of the sinkhole and the draining away of the water from Étang aux hérons, the last fish there died – approximately mid-August 2021.

Question: What is the cause of the destruction of the fish and will they return?

We take to heart your stated commitment and sensitivity to the welfare of wetland flora and fauna. We hope and trust that, by answering these questions, you show the public that you respect their concern about the devastation of the Étang aux hérons.

Yours Sincerely,

Gareth Richardson, President
Green Coalition

For more information:
David Fletcher: fletcherdavid@me.com / 514 502-5341
Patrick Barnard : pbarnard@videotron.ca / 514 463-0573

Feature image: Patrick Barnard

Read other articles about the Technoparc Wetlands

The Green Coalition is a non-profit association of groups and individuals with a mandate to promote the conservation, protection and restoration of the environment and the wise use of green and blue spaces. Founded in 1988.