Shipping accidents have increased 36.4 percent year-on-year in waters overseen by the city's maritime authority in the first half of 2013, officials said at a press conference Wednesday.

The Shanghai Maritime Safety Administration reported that 15 maritime accidents occurred in the first half of the year. Maritime accidents include ship collisions, vessels running aground and weather-related incidents.

The administration estimated the accidents caused 162 million yuan ($26.47 million) in damages, more than triple the damages caused over the same period last year.

Administration personnel rescued 2,076 people in 108 sea rescue missions over the period. Rescuers saved 99 percent of the people whose lives were in danger.

The number of accidents increased primarily due to the growing shipping traffic around the mouth of the Yangtze River, shipping company negligence and more frequent cases of extreme weather, said Chen Xiaoguang, the spokesperson for the Shanghai Maritime Safety Administration.

An inspection of 20,597 cargo ships found that some shipping companies employed unqualified sailors and skimped on equipment upgrades to hold down costs, Chen said.

The maritime authority plans to create a shipping company credibility system that will rate the companies on a three-tiered scale based on their accident and compliance records.

The authority will give companies with an A rating preferential treatment. It will strengthen supervision and may even impose penalties on companies with a C rating.

To help keep ships safe in extreme weather, the authority plans to upgrade its technology. It will first work on improved technology to guide ships in heavy fog. The Shanghai Maritime Safety Administration oversees shipping traffic along the coast from Dongshan, Fujian Province to Lianyungang, Jiangsu Province.