NI Water has indicated that its waste water infrastructure is operating at full capacity.
In August, it said construction had been stalled in 23 towns.
The provider blamed underfunding, and a backlog in necessary upgrades and expansions is delaying new housing developments being connected to the existing network.
Last week, representatives from the utility provider warned Stormont that capacity problems would get worse without additional long-term funding.
The infrastructure committee was told NI Water is facing a significant gap in funding - both in the day-to-day running of operations and on the longer term capital side.
NI Water director of finance Ronan Larkin said there was a £23m funding gap between what they needed to run the service and what was available.
On the long-term capital spending plan, he said there was a £266m gap in funding or a shortfall of about 45%.
On Thursday, O'Dowd pointed to an additional £31m in funding which came from the Stormont monitoring round earlier this month.
He said there was still an estimated "£100m gap in the budget" that he was unable to fill.