Hopewell_Rocks

On the rugged coast of Southern New Brunswick overlooking the Bay of Fundy, the majestic Hopewell Rocks attract more than 200,000 visitors annually. They come to stand in awe of the towering rock formations created by the natural forces of erosion and the highest tides in the world. A new Tidal Exploration Centre had been built with an Interpretive Centre, a 120 seat full service restaurant and public washroom facilities for the over 4000 people per day who visit the site. However, when the new Centre opened in the Summer of 1998, an acceptable means of managing wastewater had still not been found and Park operators had to truck thousands of gallons of sewage off the site every day.

Engineering Technologies Canada Ltd. (ETC) was retained to find an appropriate and affordable wastewater management solution that would be acceptable to Provincial regulators. Criteria for the on-site sewage system were as follows:

Zero discharge of effluent to the Bay of Fundy;
● Minimize impact on the site, no additional tree clearing;
● Should not require highly skilled operators;
● Modular, easy to expand

ETC recommended and designed a Recirculating Sand Filter (RSF) to treat the wastewater to advanced secondary levels. Fractional horsepower effluent pumps micro-dose an open filter bed constructed of coarse sand. The treatment process is extremely low rate and very stable. When properly operated and maintained,
the sand should never need to be replaced. The proven RSF system was the first of its kind in New Brunswick.

Achieving a zero discharge system for the treated effluent would also prove to be a challenge as the site was overlain with less than 1 metre of glacial till soil on top of massive, conglomerate bedrock. A Subsurface Drip Irrigation(SDI) system was designed to maximize the ability of the site to absorb the crystal clear effluent from the RSF. The specialized drip tubing was buried 150 mm below the ground surface which avoided problems caused by hazardous aerosol sprays. Effluent is applied in small regular doses, 24 hours per day, which optimizes its uptake by the mature trees, vegetation and biologically active rootmat layer.

The SDI effluent dispersal system was the first such system in Canada. The Park’s regular maintenance staff operate and maintain both the RSF and SDI systems without the need for additional highly skilled operators. SERCO was the recipient of several national and international awards for environmental achievement. They credit these awards in part to their environmentally friendly, sewage treatment and effluent dispersal systems.

Cape_Jourimain

A new Provincial Visitor Information Centre, an Interpretive Centre and a Restaurant have been constructed at the 675 hectare Cape Jourimain National Wildlife Area in New Brunswick. The site is open to the roughly 1.5 million people who travel to Prince Edward Island via the Confederation Bridge each year. Sand dunes,saltwater marshes, beaches and forested uplands are part of this diverse and beautiful ecosystem which is on a major migratory flight path for hundreds of bird species.

Unfortunately, the site is also characterized by a flat topography, dense clayey, glacial till soils, and a high groundwater table (see photo on left). To address the adverse site conditions, conventional on-site sewage systems would have required either large scale tree clearing or a direct discharge; neither of which were suitable options for the client. Engineering Technologies Canada Ltd. (ETC) was assigned the challenge of designing and implementing an acceptable wastewater management strategy to protect this ecologically sensitive site.

To significantly reduce the volume of sewage water to be managed, the Clivus MultrumTM composting system was selected to naturally treat all black toilet wastes. The high-strength, concentrated wastewater from the kitchen of the full service restaurant is treated to advanced secondary levels using the Canadian, Waterloo Biofilter® sewage treatment system.
The Biofilter is a recirculating trickle filter that uses highly absorbent, plastic foam to treat wastewater. This was the first commercial Waterloo Biofilter installation in Atlantic Canada.

After much research into effluent dispersal options, ETC designed an innovative subsurface drip irrigation, pressurized, at-grade, wood chip (SDI-PAW) system to disperse the crystal clear effluent into a treed area. Polyethylene drip tubing was laid down on the ground surface and covered with a thick layer of coarse, cedar wood chips. Apart from minor removal of low brush, no clearing or cutting of mature trees was required to accommodate the effluent dispersal system. The flexible SDI-PAW drip lines were designed to wind around and in between the trees which are valued for the considerable amount of effluent water they can take up through transpiration.

To facilitate regulatory approval of the unique effluent dispersal system, ETC designed and carried out a stateof-the-art, full scale hydrogeologic loading test to evaluate the capacity of the site to accept the treated effluent. An on-site potable well was used to dose the full size SDI-PAW system with increasing volumes of fresh water over a period of two months. The full scale test successfully demonstrated the ability of the site to
assimilate the projected design flow. The innovative testing program proved to be a highly effective tool to address the concerns of regulators and resulted in the timely receipt of the approvals and permits necessary for the project to proceed on schedule.

Since the site opened, effluent quality, ease of operation and general performance of the system have surpassed expectations. Tourists from all over North America have requested tours of the innovative and environmentally responsible waste management
systems.