The Environmental Protection Agency received 2718 complaints in the 2017-18 financial year and 2844 complaints the following financial year.

The agency issued two infringement notices for excessive noise in the 2017-18 financial year, with fines of $1034 and $234.

In the 2018-19 financial year, the agency issued two separate penalties for waterways pollution and two penalties for collecting rubbish outside agreed hours.

The pollution fines cost $1000 and $875, with both rubbish-related fines costing offenders $1000 each.

The agency also prosecuted one noise pollution complaint, with a penalty of $450.

In total, the notices and infringements, cost offenders nearly $5000 over two years.

Environmental Defenders Office principal legal officer Stephanie Booker said the data only raised more questions than answers.

"It is a concern that the EPA has received over 5,000 complaints in the last two years, yet only six infringement notices were issued," Ms Booker said.

The office differs from the agency in that it is a community legal service for Canberrans to assist them with environmental legal matters.

"Why have complaints increased in the last year? Is it because our population is growing? Are there repeat complaints? Is there an increase in the awareness of the role of the [agency]?" Ms Booker said.

The majority of complaints, or about 80 per cent, for both years were noise complaints.

Air pollution complaints ranked the second highest, making about 14 per cent of complaints in 2017-18 and about 13 per cent in 2018-19.

Water pollution, land contamination andlight pollution and authorised activity respectively ranked next in complaints, except for 2018-19, where there were more complaints on light pollution than land contamination.

There was one complaint regarding tree protection in 2017-18.

Before the agency moved under Access Canberra in December 2014, it was under the ACT's environment's directorate.

In the 2012-13 financial year, the agency received 1592 complaints and issued 16 infringement notices. In 2011-12, the agency received 1396 complaints and issued 23 infringement notices

Access Canberra, which now oversees the agency, said none of the fines or prosecutions in 2017-18 and 2018-19 were lobbed at builders or developers in the capital.

A spokeswoman said the agency applies "an engage, educate and enforce" approach with compliance.

"Compliance is encouraged through education, however escalating enforcement actions will be applied to those whose conduct will, or is likely to cause harm, or those who demonstrate a disregard for the law," the spokeswoman said.

"This is the preferred model as prevention of pollution is a better environmental outcome than prosecution for pollution."

ACT environment commissioner Kate Auty said this compliance-through-education approach was a common practice across the globe.

The data on air pollution and other pollution "illustrates a level of community concern".

"Without having access to the complaints and the reasons for their resolution short of the issue of an infringement notice it is not possible to determine the reasons for decisions not to prosecute," Professor Auty said.