Atlantic City’s sewer network sits low, close to the bay, and often below sea level. Much of it was built when the boardwalk was young, long before anyone planned for the flooding this coastline sees today.
For engineers and contractors handling sewer rehabilitation in Atlantic City, inflow and infiltration (I&I) has become harder to ignore. Recent nor’easters and high-tide flooding events tied to the Army Corps’ New Jersey Back Bay storm risk study have pushed the Atlantic City Municipal Utilities Authority to look hard at how much groundwater and tidal water is entering a system that was never designed for this much water pressure from below.
Two Sources of Unwanted Water in a Coastal System
Cracked or broken pipes, leaking pipe joints, and deteriorated manhole walls and joints let groundwater seep into the sanitary sewer system. Sewer inflow takes the opposite route: roof drains, yard drains, and storm connections feeding directly into a line that was never meant to carry stormwater at all.
A rising water table pushes groundwater into pipe defects even on dry days. In a city sitting this close to sea level, a wastewater collection system already carrying excess flow has almost no buffer left once a coastal storm surge hits.
Why Tidal Pressure Complicates the Fix
Atlantic City contractors use cured-in-place pipe (CIPP) to renew a deteriorated sewer main without excavating streets that flood on a normal high tide, let alone during a storm. The trunk line typically comes through that process structurally sound.
The rest of the system doesn’t get the same benefit automatically. Aging sewer infrastructure beneath the Inlet, Chelsea, and the South Inlet sits in soil that stays saturated most of the year, so a sewer main lined but infiltration persists is common once crews check the laterals feeding into it.
Common infiltration sources across Atlantic City include:
- Deteriorated sewer laterals beneath older boardwalk-adjacent blocks
- Failed main-to-lateral connections stressed by a chronically high water table
- Cracked host pipe near back bay and marsh-edge corridors
- Manhole joint failures allowing groundwater intrusion during king tides
- Root intrusion in sewer pipes throughout older residential streets
Finding the Real Source Before Crews Mobilize
A single dry-day inspection tells engineers almost nothing in a city where the water table shifts with the tide. CCTV inspection and flow monitoring for I&I, paired with smoke testing and flow monitoring for source identification, is what actually confirms whether a leak sits at the main, the lateral, the connection, or the structure.
From there, the repair follows the finding. Structural trunk-line deterioration calls for mainline CIPP. A failing service line needs cured-in-place pipe lateral lining. Tidal pressure that has separated a joint calls for main-to-lateral connection rehabilitation. A structure cracked by chronic saturation needs manhole rehabilitation. A small, active, localized leak is often best handled with injection grouting alone.
Why This Matters for Municipal Sewer Budgets
The cost of pumping and treating unwanted groundwater climbs every year the ACMUA delays addressing this, especially with the resort’s seasonal population swings adding load to pump stations each summer. Sewer overflows during heavy rain carry real regulatory consequences, and excess flow at pump stations and treatment plants gets harder to manage as sea level keeps creeping up.
Wastewater utility capacity management here means treating the network as one connected system, not a set of isolated repairs. Specifying CIPP for municipal sewer projects handles the mainline, but rehabilitating public and private sewer laterals, connections, and manholes alongside it is what actually reduces wet-weather flows in a city this exposed to tidal groundwater.
Atlantic City’s flooding risk isn’t going away. An I&I reduction program for municipalities has to plan for water pressure from below the street, not just water falling from above it.
Find a WRT-certified installer serving the Atlantic City area to assess your collection system’s full scope of I&I sources.
