Census: St. Mary population down 9.6%

St. Mary’s population loss 2010-20 wasn’t as large as some had feared. But it came close.
The release of 2020 Census figures last week showed St. Mary Parish’s population fell by 5,244 in the last decade. The parish’s three largest cities lost a total of 2,045 people.
The results followed the post-World War II pattern established when Morgan City first became a staging area for offshore energy production: As the price of oil goes, so does St. Mary’s population.
This census also showed slower growth in Louisiana and across the country than in previous head counts, and it was conducted during the COVID-19 pandemic, complicating door-to-door follow-ups to count people who didn’t respond to the census forms distributed by mail.
St. Mary’s population fell to 49,406, a 9.6% decrease from 2010, according to the 2020 Census. This census was the first since 1960 in which the parish’s population was below 50,000.
The last decade in St. Mary was dominated economically by the slide in oil prices that began in fall 2014. Prices dropped from about $112 per barrel in summer 2014 to near $40 and stayed in the $30-$60 range on the New York Mercantile Exchange for most of the decade’s second half. St. Mary employment dropped from about 27,000 in 2014 to near 18,000.
Earlier this year, state Sen. Bret Allain, R-Franklin, said at a St. Mary Chamber event that the early census results were showing a 10% population decrease in St. Mary.
Also according to the 2020 Census results, Assumption Parish’s population fell 9% to 21,309. In St. Martin, the population fell 0.8% to 51,767.
Back in St. Mary:
—Morgan City’s population fell by 7.5% 2010-20 to 11,472, a loss of 932 residents.
—Patterson’s population was down 3% to 5,931, a loss of 181.
—Franklin’s population fell by the same number as Morgan City’s: 932. That represents a decrease of 12.2% to 6,728.
Last week’s release of census data included only incorporated places of 5,000 or more. Berwick wasn’t included in the release, which means the town fell short of the 5,000 level required to be classified as a city.
The estimates released by the Census Bureau each year showed a Berwick population of 4,584 in summer 2019.
But Mayor Duval Arthur has said the estimates undercounted Berwick’s residents. Arthur pointed to an estimate from LSU that shows the population exceeding 5,000.
Yearly census estimates rely on data such as school enrollment and utility hook-ups.
The results of the 2020 Census, both for populations and for demographic data such as household income, will have an impact on the ability of local governments to obtain federal grants.
The numbers will also guide the work of redrawing the district boundaries for political subdivisions, which generally must be remapped after every census. The detailed data needed for that task has yet to be released.
Louisiana’s population growth of 2.7% in the last decade was slower than the national growth rate of 7.4%. But the state is expected to hold on to all six of its seats in the U.S. House of Representatives.
The state had eight House seats in the 1980s. But because the state’s population grew more slowly than the national population, the state lost congressional seats after the census in 1990 and 2010. Louisiana currently has six House districts.
Each state gets a number of Electoral College votes during president elections equal to its number of U.S. House seats plus its two Senate seats. So Louisiana’s clout in presidential balloting has fallen from 10 to eight in the last 30 years.