Automatic water quality monitoring networks

Controls the quality of surface waters is based on the design of a network of sampling stations defined as the selected area so that through his study would be classified the status of a body of water or submasa. Associated with each sampling station can be found different points of sampling on the basis of the variables under study, of the matrix object of study and the characteristics of the sampling point.

The network consists of a series of points of operational monitoring and surveillance, as well as network of intercalibration and the network of reference points. Taking of samples for biological and physico analysis. Biological analyses, as part of lab work involving analysis relating to the composition and abundance of the different compartments of ecosystems subject of study, i.e., benthic macroinvertebrates, fish fauna, phytoplankton, flora aquatic (macrophyte, macroalgae and Angiosperms).

Physico-chemical analysis on different matrices (water, sediment, biota) involving the control by means of the analysis in laboratory of variables associated with General and specific pollutants physico-chemical conditions. Work of cabinet which involves the collection, analysis and interpretation of information obtained as well as the drafting of the relevant reports. Control and monitoring of the quality of groundwater is carried out through the establishment and subsequent exploitation of control networks. This allows to have a knowledge of the status of bodies of water. Depending on the purpose of the control, choose a group of wells that samples are regularly taken at a frequency of certain sampling and an analytic.

There are several types of networks of quality control. First of all, surveillance monitoring networks, that perform basic control of the chemical composition of groundwater, which includes the analysis of anions and cations majority (Ca^{2 +,} Mg^{2 +}, Na⁺, K⁺, Cl^–, SO^42-, HCO^3-) and compounds of nitrogen (NO³)(, Not^{2 -} and NH^{4 +}), screening (screening) of metals, and the analysis of the COT, pH and conductivity. In budgeted risks or function of the background that may become available, there are other additional determinations.

The network is divided into a set of subnets that match the delimitation of groundwater bodies of water. Each of them subnets is defined based on geological criteria, population density, of the aquifer as it relates to its management and strategy of their vulnerability. These criteria determine that the controls are more or less exhaustive and, therefore, condition, also, the number of control points, its location, the frequency with which they take samples and parameters to be analysed.

Such networks are established in areas where a risk of groundwater condition is assumed. The first of these is the network of salinity, which aims to assess the degree of penetration of seawater for coastal aquifers. They tend to be divided into different subnets based on bodies of water with a coastal part. This network in situ analyses the conductivity, pH, temperature, the redox potential (Eh), dissolved oxygen and the concentration of the ion chloride in the laboratory.

Secondly, they often use networks of areas vulnerable to pollution by nitrates. This type of network is defined by having knowledge of the State of the water quality in vulnerable areas in relation to pollution from nitrates from agricultural sources, as it establishes the regulations in force. The analysis is normally done are those of the cycle of nitrogen compounds. In situ analyses the conductivity, temperature, pH, the Eh and dissolved oxygen.

On the other hand, the networks of pesticides are intended detect the presence of pesticide compounds in groundwater in zones which is dominated by agricultural activity. Insecticides are in registration of pesticide compounds which are detected and measured, organochlorine and its major metabolites, organophosphate insecticides and herbicides of the family of triazines.

In addition, episodes of contamination detected in groundwater monitoring takes into account polluting compounds to differentiate those episodes where the pollutants are organic compounds of those to which they are metals. Each of the episodes is defined depending on geological criteria, their vulnerability and the localized pollution stain. These criteria determine the amount of points of control, its location, the frequency with which take samples and the parameters that should be discussed.

Groundwater is one of the most important natural resources. It is one of the main sources of water for human consumption and also provides water for irrigation, livestock and industry. It also helps to maintain the flow of rivers and wetlands. Control of these resources is done through a unique network of groundwater level control. There is a set of piezómetros distributed over the territory based on the characteristics of aquifers must be controlled, and which is measured each month at what depth the water is.

Some of the piezómetros have a limnígrafo, that allows to obtain data from the continuous depth. Currently you are automating control points, so hourly or daily measurements are automatically loaded into the database of the ACA. This automation allows levels continuously and to have these data at the same time are recorded.