Programs for reusing the sludge produced in the process of the water treatment, using GIS for its control and monitoring its application.
In Murcia Region WWTPs are producing 135.000 tons of sludge yearly. This is a huge source of organic matter and nutrients, very appreciated in an agricultural region as Murcia. But this practice could be the origin of many problems if we don´t manage it properly. Problems as odours, insects or pollution of soil and aquifers could be caused by a bad management of this product. Due to these circumstances the control of the use is strong in the region.
A strong control of the sludge, from the production in WWTP until the use to amend and fertilize the soil and crops should be carried out. A third of the total produced sludge is composted and two thirds are applied directly in agricultural soil. To avoid any problem with this application there is a control system to know the track of the transport trucks, the moment in which the sludge is unload and when it´s foreseen the application on the soil. Of course also the characteristics of the sludge and the plot in which the sludge will be applied are known previously, to control the tons could be applied in the plots, regarding environmental and agricultural issues. A random control is carried out to check if the application on soil is correct.
Resources needed
The cost of the control is, mainly, the development of the app to control the track of the transport trucks and the ESAMUR staff to carry out the following and control. Moreover the analysis to know the characteristics of sludge and soil.
Evidence of success
Sludge is a problematic product that created in the past many troubles with citizens and municipalities, mainly due to odours and insects. With the new control system, the troubles have disappeared, the farmers are happy with the product they receive and it´s running a viable and safe system for a waste like the sludge.
Difficulties encountered
Social rejection to the fertilization with compost from WWTPs and the Boron contained in the sludges could be dangerous for some crops like citrus crops.
Potential for learning or transfer
Of course, this practice can be carried out for any region as Murcia with needs of organic matter and fertilizers, not rainy and with a high production of sludge due to the high number of WWTPs running.
Please login to see the expert opinion of this good practice.
Tags: Farming, Sustainable, Waste, Water
