Houma Water Hardness & Quality Report (2026)

Terrebonne Parish Consolidated Waterworks District No. 1 provides drinking water to Houma and surrounding areas in Terrebonne Parish, Louisiana, serving over 105,000 residents. Primary sources include surface water from the Gulf Intracoastal Waterway (GIWW) at Houma (USGS site 07381330) and groundwater wells, with public supply withdrawals totaling about 5.81 million gallons per day (5.20 Mgal/d surface, 0.61 Mgal/d groundwater) per USGS data. Treatment facilities manage salinity intrusion, with the utility purchasing additional supplies to meet demand amid rising Gulf influences. Contact: 985-879-2495.

Houma's water draws from the Atchafalaya River Basin watershed and coastal estuaries feeding the GIWW, shaped by the Mississippi River Delta's Holocene sediments. The underlying geology features the unconsolidated Gulf Coast Aquifer system, including the shallow Evangeline Aquifer (Pleistocene sands and gravels) and the deeper Jasper Aquifer, interbedded with Tertiary clays. These aquifers interact with surficial marsh deposits containing shell marls and limestone fragments, while surface waters experience tidal mixing with brackish Gulf inflows — the calcareous coastal geology imparts a moderately mineralised to hard character to the supply.

At moderately hard to hard levels, Houma's water promotes limescale buildup in pipes, reducing flow efficiency, and shortens the lifespan of water heaters, dishwashers, and washing machines by 30–50%. Faucet aerators and showerheads clog quickly, increasing energy costs. Monthly vinegar soaks for fixtures, annual descaling of appliances, and sediment pre-filters are recommended; a water softener is advised to prevent spotting on dishes and dry skin and hair. Tap water in Houma meets all EPA Maximum Contaminant Level Goals (MCLGs), with all tested contaminants below health-based guidelines; check the annual Consumer Confidence Report for updates.