(Less than) 50 Shades of Brown

Most likely, this morning some of us went to the bathroom, brushed our teeth, took a bath, and did our things in the toilet, maybe followed by washing the dishes that have been sitting on the sink since last night dinner. Little did we know, the water (or better we call it wastewater) that we used is flushed and drained to a collection pipe. In the case of EM-41 class, our wastewater is collected by sewer pipes in Dresden which has a total length of 1700 km with diameter of up to 2 meters.

These pipes are laying under the roads of Dresden and deliver our wastewater to a specific plant in Kaditz, an area northwest of Dresden. Occupying an area as large as 25 football fields, the plant was constructed in 1910 to treat the wastewater produced by Dresden’s population. Currently, everyday approximately 120.000 m3 of wastewater coming from 700.000 people is reaching the treatment plant. Since Dresden’s wastewater system applies a combined system, the incoming wastewater is collected together with rainwater and treated together in the wastewater treatment plant (WWTP).

To give you some illustration about the smell that we inhaled that afternoon, here is a picture of raw wastewater which just arrived in the WWTP; a dark-brown water.

Pic 1

Dirty, hence the dark color. Full of organic materials, which could lead to oxygen depletion in the aquatic ecosystems.  Full of microorganisms, which some are harmful to humans, and of course smelly. And these are the shades of brownish colors of the same wastewater during the treatment processes:

More or less 24 hours later, we will receive this not-even-close-to brown water, which is the treated water from the WWTP.

Pic 4

Almost like clear water, it is still not safe for drinking, but is now safe to be discharged into receiving water bodies, in this case the famous Elbe River. With only 5 mg/l of Biochemical Oxygen Demand (BOD5), and 41 mg/l of Chemical Oxygen Demand (COD), NH4-N of 0,7 mg/l, N total of ±13 mg/l, and P Total of 1 mg/l, this water won’t be a harm to humans and neither to the environment once it is discharged into the river.

How could the wastewater be turned into clear water? The answer is because of several physical, biological, and chemical processes that were taking place in the plant. At first, the wastewater was treated with physical and mechanical treatment with bar screens and grit chamber to remove the trash and to remove sand subsequently from the wastewater. The water then underwent a sedimentation process in which its floating and settle-able solids sink to the bottom of the tank. Afterwards, the water was transported to aeration tanks. In these tanks, air bubbles were introduced to the water to be used by the microorganisms which “eat” the organics. The water then again settled in secondary sedimentation tanks, from which it can then be safely discharged to receiving water bodies.

The sludge coming from the primary and secondary sedimentation tanks was also treated in a series of sludge treatment units. Unfortunately, we did not have the chance to visit all the units, but we could see from afar the two giant egg-shaped anaerobic digestion tanks.

We had fun during the visit, especially since the weather was rather nice today. And since 81% of the energy used is produced by the plant (mainly from anaerobic sludge treatment units and small amount produced by solar systems), we proudly took a picture in between the solar panel systems.

Pic 5

by Vika Ekalestari (Indonesia)

special credit to Tamara Karp (CIPSEM) for the title idea 😉


Excursion to Waste Management and Recycling Facilities


In Saxony waste management involves many stakeholders (including private, public and PPP`s) and has a very interesting social aim. Led by Dr. Dietmar Lohmann, we had two days of excursions (January 31st and February 1st) to many waste management facilities.

It was very interesting to know more about the German management model, in which consumers and producers are economically responsible for waste management. The inclusion of handicapped people in waste business was nice and surprising, becoming definitely a role model to be analyzed and implemented in developing countries.

We had the opportunity to see new technologies for bio-waste treatment, like the quick fermentation chambers at the composting facility. Although it is important to mention that some other processes at this facility, like compost maturation and marketing, surely can be improved.

In developing countries may be difficult to find waste to energy projects, but here in Germany we had the chance to visit a landfill-gas utilization project, in which biogas was transformed into energy for the grid.

Also we were impressed by the willingness of Germans for buying recycled products, as we saw the success of PAKA, a cardboard recycling company with more than 100 years of history. We have to highlight the way they market their products and find specific and lucrative niches.

These excursions were a wonderful experience for us, but also a great chance to have nice moments with our fellows.

by Gabriela de Jesús Fernández Tay (Cuba) & Eduardo Esteves (Ecuador)

New year, new group

Today, we could welcome the participants of the 41st UNEP/UNESCO/BMUB International Postgraduate Course on Environmental Management for Developing Countries. From the first impression, we can be glad to work with a group of dedicated individuals on the manifold aspects of environmentally sustainable development during the next six months. We will keep you updated!


Here are some impressions from the opening ceremony (pictures by Harald Schluttig).


Excursion to the Botanical Garden of TU Dresden

As a part of the programme of the 71st UNEP/UNESCO/BMUB International Short Course on Ecosystem Management – Biodiversity Conservation and Ecosystem Services, our diverse group from 21 countries (mainly from the tropics and subtropical areas) had the experience to visit an important place for tourists, scientists and environmentalists alike: The Botanical Garden of TU Dresden. With an extension of three hectares, the garden is home of around 10,000 species of native and exotic plants, that had been well preserved and managed by specialized gardeners, volunteers and dedicated scientists since 1822. Today the scientific head of the Botanical Garden is Dr. Barbara Ditsch, a woman with great knowledge and passion regarding plant conservation and management and to whom we are deeply grateful for sharing her knowledge and warm hospitality.

During this pleasant excursion, we could find a variety of native and endangered plants included in the red list of Saxony as Arnica montana; medicinal and toxic herbs as Colchium autumnale, tropical and subtropical aquatic, carnivorous or ornamental plants as Victoria cruziana, Nepenthes sp. and orchids respectively, as well as perennial plants and deciduous trees from Europe, temperate Asia, North America and the Mediterranean region. Also our excursion was warmed up with the visit into three wonderful and well managed greenhouses showing the tropical and subtropical regions, and even the humid weather of the Amazon or the warm and dry weather of Madagascar desert.

New concepts of conservation and plant management have been provided to our pool of knowledge, where we could learn that The Botanical Garden of TU Dresden is working with the aim to integrate several innovative proposals towards an important topic in this decade: “Ecosystem services”. In which it is relevant for the ex-situ plant conservation and for the local animal diversity (e.g. providing habitat for 120 bees that have been recorded here and in its surroundings), but also providing a harmonic space for tourism, education and research (estimated 100,000 guests/year), highlighting the multiple roles of botanical gardens within urban areas. This experience had contributed both in our cultural enrichment and also in our professional knowledge, in which the majority of us will be very glad to bring this innovative and multidisciplinary idea of conservation for our countries.


by Vanessa Wätzold Ospina (Colombia)


Celebrating new friendships and the last days of summer

We are enjoying summer while it lasts. Today we had a barbecue with both the participants of the Ecosystem Management short course and participants and facilitators of the INOWAS summer school on managed aquifer recharge. It has been good to recharge the batteries after a long day of excursion and classes and a nice opportunity to get to know each other (better) … and also to witness so many barbecue styles.


What keeps Dresden moving?

Excursion to DVB Mobil – Dresden

From the day we first landed in Dresden, we admired the transport system in this lovely city i.e. the trams and buses especially by the level of efficiency and time management! How does this system operate so well? We wondered. On 23 March 2017, we finally got the answers, through an excursion to the Dresdner VerkehrsBetriebe (DVB) Mobil, the public transport company in charge of transport services in Dresden. Winfried Oelmann the head of operations gave a presentation on the company operations, specifically on the history of the company, work environment, training opportunities, route network, ticketing system, infrastructure, social activities among other things. The overall presentation was quite enlightening.

Afterwards, we were taken to the control room which operates 24/7 and it is where all the action happens. We got to learn how the entire system is synchronized i.e. the route network, time & efficiency of the trams and buses. There is also a customer care hotline which operates fulltime to respond to any inquiries or emergencies. Basically, this section is the heart of the company!

Key lessons learnt: 

There was so much to learn from this excursion it would not be possible to exhaust it all in this article. However, in summary, the highlights were;

  • Efficiency: DVB is highly efficient, ensuring all trams and buses operate as scheduled and all the route networks are operational through the control center
  • Incentives: DVB offers incentives to companies, students and the general public through discounts on individual and group tickets hence encouraging people to use public transport. From the environmental perspective, the more people use public transport, the less vehicles on the road and therefore less carbon emissions ☺
  • Public relations: DVB has a strong social media presence and a customer service team to keep the public informed/updated and to respond to enquiries and/or emergencies.

Overall, it was a great experience and there is so much our countries can borrow from this system, which would go a long way in improving most of our public transport systems and most of all, restoring our faith in government-run systems. Many thanks to the entire DVB team that made this excursion a joy!

Text and photos by Joyce Kiruri, EM40 course participant from Kenya.


So, how good is the air you breathe?

In critical physical situations, the longest time that people can survive without water is 3 days, without food is 3 weeks, but without oxygen from air is only 3 minutes. It is remarkable how air is the by far most important requirement for life on this wonderful planet.

On 06 March 2017, we had an excursion to the Air Quality Monitoring Station in the Neustadt part of Dresden which is one of 29 fixed automatic monitoring air quality stations in the network of the Federal State of Saxony. Among those, each station measures meteorological parameters (temperature, wind direction, wind speed, precipitation, humidity, etc) and air quality parameters (PM10, PM2.5, NOx, SO2, O3, BTX, etc).

By the time we have visited the station, the data showed that PM10, NOX, and O3 were 20.3 µg/m3, 0.125 ppm, and 11 ppb. Whereas the Benzene, Toluene, m.p-Xylene, and o-Xylene (BTX) were recorded 0.8, 1.8, 1.5, and 0.6 µg/m3, respectively. “These data show that no parameter exceeds EU standards. However, concentrations at the Neustadt site are still higher than at other sites in the city of Dresden. This may be linked to the station’s position where traffic is characterised by high vehicle density”, said Dr. Kath, air quality expert from the Saxon Environmental Operating Company (Staatliche Betriebsgesellschaft für Umwelt und Landwirtschaft, Sachsen). In addition, due to the weather conditions at the time, air emission from vehicles activities could not be well mixed into the atmosphere.

Finishing the excursion, the Earth still moves, all of us still have to breathe, and cars still run on the road with emissions. Let’s enjoy the fresh air after the rain but remember that more actions need to be taken to protect our living environment.


Text and photos by Dr. Hoang Anh Le, EM40 course participant from Vietnam.