Well Done: You now discharge 60% less Nitrogen and Phosphorus to streams than you did 15 years ago.

A big pat on the back to the collective wastewater management industry in Queensland who have achieved up to 60% reduction in the amount of nitrogen and phosphorus discharged to the environment from 1999 to 2011.

 

Often all that stands between a healthy waterway and a skanky stream chocked by algal blooms which is devoid of animal life except for the toughest of invasive species is a little nutrient enrichment. One of the biggest, or at least most concentrated sources of nutrient enrichment comes from every time we flush. Our local councils are the recipients of our unholy discharges and together with the rather unglamorous wastewater industry have been quietly protecting our environment by cleaning up our wastewater treatment plants.

Firstly, consider Nitrogen. In 1990 4,360 Tonnes where discharged by major industries to waterways in Queensland. Compared to 2011 this has been dramatically reduced to 1,760 Tonnes (Figure 1). Similarly, the total discharge of Phosphorus has reduced from 1,540 Tonnes to 680 Tonnes (Figure 2). That is an overall reduction of 60% for nitrogen and 56% for phosphorus discharge in 12 years which is pretty impressive.

The data

In Australia, state governments license discharges to the environment, and for prescribed industries these are reported nationally under the National Pollution Inventory (NPI). I have recently collated the annual discharge of pollutants reported by the Qld Government to the NPI. There are tens of different chemicals which are reported for the NPI and all major industries which you can check out in the sample data on Truii. However, for this post I will focus on Nitrogen and Phosphorus discharge from wastewater treatment plants as these nutrients are often limiting in our streams and rivers. By ‘limiting’ we mean that one of these nutrients is all that stands between a healthy stream and one chocked by algal blooms or generally poor water quality.

 

Figure 1: Total Nitrogen discharged to Qld Waters as reported to the National Pollution Inventory

 

Figure 2: Total Phosphorus discharged to Qld Waters as reported to the National Pollution Inventory

It is pretty obvious from Figures 1 and 2 that the lion’s share of nitrogen and phosphorus discharged to waterways is from the water and wastewater industry. This is mostly from all those council run or contracted treatment plants that treat the stuff that we all flush down our toilet. There has been a long and concerted effort by councils to upgrade their treatment plants and adopt the best treatment technologies. Figure 3 shows the dramatic reduction in the total load of Nitrogen and Phosphorus from the water and wastewater industry over the 12 year reporting period.

If you want a neat number to show how your council rates have been spent – in 1999 every Queenslander was responsible for 1.15kg of Nitrogen and 440g of Phosphorus discharged to waterways. In 2011 that personal pollution had dropped to 340 grams of Nitrogen and 140 grams of Phosphorus per Queenslander. That seems pretty good, but not every council is pulling their weight.

 

Figure 3: Total Nitrogen and Phosphorus discharged from water and wastewater treatment plants for Qld.

[pullquote] Toowoomba, Ipswich, Redland and Brisbane are the standout performers[/pullquote]
The performance of the major municipalities (Figure 4) shows that the Sunshine Coast Regional Council are the laggards; Logan City Council is inconsistent; Gold Coast City Council is doing OK but trailing the leading pack which is made up of Toowoomba, Ipswich, Redland and Brisbane. It looks as if the major improvements in wastewater treatment had been implemented by around 2007, and the collective councils seem to now be resting on their laurels (notice the flattening in Figure 4 over the last few years).

 

Figure 4: Percentage improvement in Nitrogen reduction by council area within Qld.

The complete data set is available in the ‘Environmental Data’ library on Truii.com. I have also compiled the NPI reporting discharge to air for Qld – so you can see which industries pump out the most noxious gas. This library also has the national CO2 emissions reporting.

About the data visualisations

The visualisations in this post are contained within their own Dashboard. You can link to the dashboard, or use the shortcode from each viz to embed or link to specific Viz’s in another web page. You can simply ‘like’ any of the visualisations to post them on your social media feed.
The viz’s are easy to make. All you need to do is create a free Truii account to create and publish your own data visualizations.
Don’t forget to sign up to Truii’s news and posts (form on the right).