The management of leachate flow is a challenge for the operation of landfills in Morocco. This Essaouira which started in 2001, received in 2014, 72 tons of waste as daily average. This buried tonnage generates between 6 and 8 m3/d leachate
The objective of this study is to follow the evolution of the physico-chemical composition of leachate stored and therefore assess the purification performance of the adopted treatment system. To do this, leachate samples were collected and analyzed during the period from 2012 up to 2015. The analysis results show that despite the long stay in the leachate storage basin, the pollution organic and inorganic filler, is significant and almost stable over time.
The organic pollutant load is expressed as COD varying between 6106 and 13939 mgO2/L with a mean of 10361mgO2/L. It also resulted in BOD5 which is between 207 and 851 mgO2/L, with an average of 631 mgO2/L. Therefore the ratio of BOD5/COD is between 0.03 and 0.08 with an average of 0.06. This shows that the leachate studied are old and characterized by complex organic load and nonbiodegradable.
Mineral pollution is also present and marked by a high electrical conductivity which reached an average value of 39983?s/cm. The values of this organic and inorganic pollution, far beyond the limits of direct discharge into the receiving environment.
The metal composition of leachate is typical of landfills for household dominant. In fact the values obtained during this monitoring does not exceed the thresholds set by the Moroccan standard rejection besides chromium (avg=1720 mg/l) which has a much higher concentration than other discharges and which exceeds Moroccan standards rejection (avg=200?g/l).

Heavy metals are micro likely to cause nuisance even when they are released in very small quantities (toxicity develops through bioaccumulation). Moreover, small amounts are often offset by a volume effect into account the importance of water flow. The industry is responsible for almost all releases of heavy metals in water. In effect, water rivers, streams, canals, the sea has long been "outlet" that allowed to evacuate waste. This work focuses on the analysis and evaluation of metal contamination of raw sewage drained by three main collectors Oued R'dom (Morocco) through the spatio-temporal monitoring of the levels of some metals (Pb, iron, Zn, Cd, Cu and Cr). Sampling was conducted for one year from January to December 2013. Analysis of Fe, Zn, Cd, Pb, Cr and Cu revealed the presence of metal contamination from the Fe exceeded the threshold of acceptability, other metallic trace element exist in quantity accepted, they could be classified in order of abundance in the following manner: Fe> Zn> Cd> Pb> Cu> Cr. The average concentrations of metals Oued R'dom level in water are 3.11 mg / l for Fe, 2.17 mg / l for Zn, 0.046 mg / l for Pb, 0.01 mg / l for Cr, 0.043 mg / l for Cu and 0.083 mg / l for Cd.