Sewerage Authority mitigation plan reduces risk of environmental disaster

LINCROFT, N.J. — Among the most devastating effects of Hurricane Sandy in New Jersey was the storm’s impact on sewage treatment facilities along the coast. During and after the storm, sewage plants and pump stations along the coast were inundated by flood waters and without power for as long as three days, resulting in the discharge of some 2 billion gallons of untreated and partially treated sewage into New Jersey waterways, according to the New York Daily News.

The environmental damage was unprecedented — and the financial impact was devastating. Total costs to repair and reconstruct the damaged sewage treatment facilities now top more than $100 million. With the help of Public Assistance Grants, sewerage authorities throughout the state have acted to reduce the risk of a similar disaster through mitigation measures that include constructing flood walls, elevating sensitive equipment, and relocating vulnerable facilities out of the flood zone.

In southern Monmouth County, the South Monmouth Regional Sewerage Authority owns, operates and maintains 11 sewage pump stations in Belmar, Brielle, Lake Como, Manasquan, Sea Girt, Spring Lake, Spring Lake Heights and Wall Townships. The majority of the Authority’s sewage pump stations were constructed and placed into operation in the 1970s. But in Sea Girt, the authority converted an existing facility constructed in the 1900s.

By 2006, that facility had outlived its useful life and the Authority made plans to replace it. The Sea Girt pump station had been flooded in the past, and the likelihood was high that it would experience repeated flooding. While the Authority considered relocating the facility, that idea was not feasible because of the cost, permitting restrictions and the lack of available land in the heavily residential community.

Instead, the project team comprising Authority officials and project engineers worked together to design a facility that could remain within the footprint of the old plant but that would be better equipped to function and survive during a major storm. The plan they decided upon called for a mobile trailer for the pumping station’s most sensitive equipment. The trailer can be moved out of harm’s way when flooding threatens.

An esthetically designed portable trailer houses an emergency generator, a successful mitigation project South Monmouth Regional Sewerage Authority (SMRSA) implemented in its Sea Girt pump station before Superstorm Sandy struck.

The enclosure consists of two rooms, one sound-attenuated room for the emergency generator and another climate-controlled room for the electrical equipment, including controls, alarm systems, variable-speed drives, Supervisory Control and Data Acquisition, and various other components. Electrical and control connections between the enclosure and the pump station and its equipment are made with cables and plugs that can be opened to permit removal of the enclosure.

The trailer can be removed when emergency management officials notify the Authority of an impending storm. When the trailer is removed, an expendable portable generator and transfer switch is put it in its place, allowing the pump station to operate even when utility power is lost. This secondary, sacrificial electrical and control system, mounted on the site, powers the pumps and other equipment on utility or generator power until destroyed or damaged by flooding.

Once the storm subsides, the mobile trailer can be moved back into place and put back on line. The mobile trailer plan minimizes any damage to the station’s electrical equipment and significantly reduces downtime for the station.

The cost savings is also substantial: A generator may cost $60,000 to replace. The cost of reconstructing a pump station and providing emergency generator capacity until power is restored to the site can cost hundreds of thousands of dollars.

“The mobile enclosure saved the Authority an estimated $1.5 million dollars in repair/recovery monies as a result of the fact that there was no substantial damage to the Sea Girt Pump Station during Irene or Sandy,” said South Monmouth Regional Sewerage Authority Engineer Ryan Krause. “There was no loss of sewer service to residents and no sewer service overflows.”

The station is then able to return to normal operation within hours of the passing storm, rather than days, weeks, or months, as required to rebuild or reconstruct the facilities. A faster recovery for the sewer system reduces the public health risk that can result when untreated sewage is discharged into waterways or into the community.

The Sea Girt pump station complements Governor Chris Christie’s goal to make New Jersey’s infrastructure resilient and is considered a model for Best Management Practice for sewerage and water authorities, enabling continuous operation during adverse weather events, thus eliminating or substantially reducing the potential for an environmental disaster caused by the release of untreated sewage.

As a result of the steps the Authority took to mitigate the site, the infrastructure survived and the Sea Girt Pump Facility became operational within hours.

The SMRSA, has recently been awarded a FEMA grant for a “least cost alternative project” which incorporates the mobile enclosure concept for its Pitney Avenue Pump Station in Spring Lake, N.J., and is evaluating the feasibility of incorporating this innovative design for its Belmar Pump Station, both of which were damaged during Sandy. The FEMA grant for Pitney Avenue PS is for reimbursement of 90 percent of the eligible cost(s) up to $1,201,428.00.

The two mobile concept facilities, developed here in Monmouth County, are the only two in the world. Because of its success in mitigating damage from Hurricanes Irene and Sandy, the concept is being considered by FEMA as a nation-wide Best Management Practice for mitigation of potential damages to equipment as a result of a flood event.

Additional information on the Sea Girt mobile enclosure can be found at the Authorities website, www.smrsa.org.