Factories already in production but failing to meet regular assessments will be fined or even closed if they fail to make technical improvements to meet environment standards. Such evaluations were later extended to companies seeking a domestic market listing.

In 2008, the State Environmental Protection Administration was upgraded into a ministry directly accountable to the central government, giving it more clout with the provincial authorities.

In the last five years, Shaanxi Province has closed 134 paper mills with total waste discharges accounting for a quarter of the total COD in the Weihe River. Moreover, 50 sewage treatment plants had opened in the river valley by April.

"These measures worked, but are far from enough. Combating water pollution in the Weihe River will be increasingly difficult," said Li Xiaolian.

According to the provincial environmental authorities, the composite pollution index of the river's main stream fell from 9.04 in 2003 to 2.09 in 2009. The improvement means the river water can be only used for irrigation, but is not good enough for swimming or aquatic farming.

With industries pumping in wastewater laced with heavy metals, including chrome, arsenic, cadmium, lead and mercury, the river used to be dark and foul smelling in 2004.

The 818-km Weihe River flows through Xi'an, Xianyang, Baoji and Weinan and used to nourish 56 percent of the province's arable land. The river valley, home to 64 percent of Shaanxi's population, generates about 80 percent of the province's yearly gross domestic product.

Calling the penalty "an alarm bell at the right time," Shi Ying hoped local governments could realize that closing polluting plants was only a quick fix. "A long-term approach should be to restructure industries in the river valley and aim for coordinated development across it."

Of Shaanxi's 10 cities, capital Xi'an is the biggest economic engine, but was also the first to be fined. When it was fined in March, the city was competing to be the province's Environmental Protection Model City.

"The penalty shook us up a lot", said Dong Jun, Executive Vice-Mayor of Xi'an. "It reminded us of the necessity to transform our growth mode and to curb pollution by optimizing industrial structure."

In response, Dong said, Xi'an rejected all traditional industrial projects at this year's China East-West Cooperation and Investment Trade Fair in April and signed only high-tech projects.

Ren Yongfeng, deputy director of Xi'an Environmental Protection Bureau, said the city environment watchdog would also press lower-level governments to make more solid efforts to curb pollution.

Refusing to disclose the penalties facing county or district authorities, Ren said the criteria would soon be submitted to the mayor's work meeting for discussion.

In late May, China's top economic planner, the National Development and Reform Commission (NDRC), also showed rare toughness, threatening to punish provincial governments and key enterprises that fail to realize the year's missions in environmental protection and emissions cuts.

The government planned in 2006 to axe the country's energy consumption per unit of GDP by 20 percent by 2010. The past four years saw the figure decline by 14.8 percent.

In the first quarter this year, six industries -- power generation, iron and steel, non-ferrous metals, building materials, petro-chemicals and chemicals -- reported a rise of 3.2 percent in the per-unit energy consumption. Moreover, 12 of the country's 31 province-level regions also reported a rise, according to the NDRC.

Regarding 2010 "a year of decisive battles" for China to meet the goals set for the 11th five-year period and pave the way for development in the next five years, the NDRC has promised to publish its evaluation reports at the end of the year and penalize those that fail and reward excellence.

"The message is clear here. Governments at various levels failing to protect the environment would be named, shamed and pay the price," said Shi Ying.