Culvert Replacements and Drainage Retention Area Design

The City of Beverly was grappling with severe flooding during major storms along Chubbs Brook, which was causing significant damage to the area. To tackle this issue, BETA was engaged to design a solution that would address the problem and improve the resilience of the community.

The project involved designing two culvert replacements and a stormwater detention area. The two existing culverts, located under a state-owned road and the MBTA’s commuter rail tracks, were replaced with new culverts that provided additional drainage capacity at the two crossings. The new culverts measured 6’ x 4’ and 8’ x 4’.

To provide additional flood protection, BETA designed a stormwater retention area that features two walls at the required elevation with drainage pipes running through them. During normal conditions, water flows through the drainage pipes as expected. But when a severe storm is forecasted, the pipes can be valved off, holding back the stormwater until the Chubbs Brook has drained sufficiently to release the water back into the brook.

The permitting process for these projects was critical. For the MBTA culvert, which was located next to a salt marsh, special care had to be taken to ensure that the protected area was not harmed during construction. The new culvert had to be built in the footprint of the existing culvert to comply with permitting requirements.

Similarly, for the stormwater retention area, which was constructed next to a wetland, BETA coordinated with the local Conservation Commission and MassDEP to ensure compliance with all regulations and to use the wetland as a natural drainage area.