The oil and natural gas division of the North Dakota Industrial Commission said oil production for May, the last full month for which data are available, was 1,039,635 barrels per day, a new all-time high and a 3.8 percent increase from April.
April was the first time output from the region passed the 1 million bpd mark. More than 90 percent of the oil produced in the state comes from the Bakken and Three Forks area.
NDIC Director Lynn Helms said in a statement Monday some of the activity in the region was curtailed by inclement weather.
"North Dakota leasing activity is very low, consisting mostly of renewals and top leases in the Bakken - Three Forks area," he added.
There isn't enough pipeline capacity to take oil out of North Dakota, prompting energy companies to rely instead on rail for deliveries to refineries. Helms said the capacity to get oil out of the state was adequate so long as rail deliveries continue to increase.
Enbridge Energy in June received the necessary permits from the North Dakota government to start building the 616-mile Sandpiper pipeline, which the company says could move more than 20 percent of all the oil produced from the Bakken reserve area.