Petitcodiac River Causeway

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The causeway carries Highway 114 connecting Moncton on the north bank with Riverview on the south bank.

It was constructed in 1968 by the New Brunswick Department of Transportation using federal funding for provincial highway infrastructure expansion. The structure completely blocked this tidal portion of the upper reaches of the Petiticodiac River estuary, although there was a set of sluice gates installed at the southern end to permit periodic water discharge.

The resulting causeway structure acts as a dam, creating an artificial headpond on the upstream side. On the downstream side, the effects of the causeway were noticeable within several years as the river began to fill with silt, owing to the blocked water flow. By the 1980s, the famous tidal bore along the Moncton and Riverview waterfronts was reduced to a mere ripple and the river course had been severely altered through land accretion and oxbows.

Bridge replacement

In August 2007, the New Brunswick Department of Transportation announced that it had accepted that the causeway must be replaced and that it was designing a 280 metre bridge carrying a 4-lane highway to be constructed parallel to the existing causeway on the downstream side at a cost of $70 million. The projected date for the bridge to open is sometime around 2012, after which the causeway would be removed by 2015 to return the river to its natural flow, almost 50 years after the cauesway was built.

Arguments for removal

During the 1990s, a group of concerned citizens formed Petitcodiac Riverkeeper to work with the provincial and federal governments to remove the causeway and replace it with a bridge to permit the river to return to its natural flow. They noted that the causeway structure was in complete violation of the federal "Fisheries Act" in that it prevented fish passage and has contributed to the loss of indigenous fish species in the river.

Arguments against removal

A minority of land owners in the town of Riverview whose properties abutted the headpond have opposed any decision that would see the river return to its natural flow, since this would negatively affect their property values. The headpond provides a small amount of recreational value to residents of the Greater Moncton area. Also, there is no guarantee that the river would naturally restore itself to pre-causeway conditions. The Petitcodiac River is not in as good shape as it was prior to the causeway, and this could have a negative effect on the river and the adjacent Petitcodiac Lake.