The environment in parts of North China's Hebei Province has deteriorated sharply, an inspection team jointly dispatched by the State Council and the Ministry of Environmental Protection (MEP) said Tuesday.

The Canglangqu River, Shibei River, Liaojiawa River and Chahe River in the province's city of Cangzhou are all heavily polluted, with average 2015 pollutant concentrations in all four up 30 percent from 2013 figures, inspectors noted.

Meanwhile, the total phosphorus index for rivers emptying into the Daheiting Reservoir in Langfang was up 275 percent over 2013, and the overall water quality of the reservoir was categorized as polluted and unfit for use. Several rivers in Langfang were also found to be full of sewage discharge, prompting a group petition from residents downstream.

Several illegal development projects were discovered throughout Hubei, including the construction of villas near the province's protected drinking water sources.

During the inspection, 200 enterprises were shut down and 123 people were arrested.

Inspectors attributed the environmental violations to ineffective supervision by local regulators, some of whom fabricated information about the abandonment, replacement and upgrading of furnaces in use at industrial facilities.

"Former leaders of the provincial committee of the Communist Party of China (CPC) didn't take environmental protection seriously and failed to make changes from 2013 until July 2015," the team said.

The Party chief in office in Hebei from 2013 to 2015 was Zhou Benshun, who was expelled from the CPC and removed from his post in October for offenses including graft, speaking against the Party line and hindering an official investigation.

The inspectors, who were dispatched to Hebei from December 31 to February 4, ordered local authorities to submit proposed rectification measures to the State Council within 30 work days.