**3.1 General considerations**

It is not only owing to its environmental importance but also because of its economic, social, and touristic value that the quality of the waters of the Rodrigo de Freitas Lagoon is the object of constant research projects that seek its improvement.

The basic aim of the program called the "Assessment of the Quality of Water in the Rodrigo de Freitas Lagoon and the Rivers and Canals" attached to it is to examine the environmental management of the system formed by its water bodies. Its scope covers the obtaining of environmental information in real time, combined with services for the collection of samples and physicochemical and biological analyses to form a database that can allow an investigation to be carried out of the quality of the water of the Lagoon in the face of natural and anthropic interferences.

Bulletins are issued on the "Quality of the Water in the Lagoon" on a daily basis, and these provide information about the condition of the water with regard to protecting the aquatic communities and making a secondary contact classification (i.e., "appropriate" or "inappropriate"); these are then published in the bulletins from the Center of Operations of the City Council (COR) and also in the Portal of the Council. In the case of the classification of secondary contacts, a limit for the density of 2000 NMP/100 ml of *Escherichia coli* was established for at least 80% of the six samples collected for each of the three areas established in the Municipal Decree 18.415/2000, in accordance with the methodology employed by CONAMA 357/2005.

**33**

every 15 minutes.

*Environmental Monitoring of Water Quality as a Planning and Management Tool: A Case…*

The control of the quality of the water in the LRF has been carried out by TECMA since 2011, through a contract for undertaking services that include data collection, analyses, making results available, and drawing up periodical reports for

The main purpose of the current monitoring which depends on specific and continuous collections is to follow the physical, chemical, and biological alterations resulting from anthropic activities. It also examines the natural phenomena which can impair the quality of the water both for the protection of aquatic communities and for sporting activities in secondary contact and thus recommends what necessary measures should be taken to maintain the quality of the water of

The Lagoon requires constant monitoring since it is a naturally vulnerable system that is subject to natural phenomena like stagnation and the deterioration of the quality of the water, the emission of gases, silting, and the high mortality rate of fish [9]. These kinds of problems can be aggravated further by intense urbanization

The specific monitoring of the Lagoon is carried out in six sampling stations, codified from LRF1 to LRF6, with collections being made twice a week by means of portable field equipment and then sent to the laboratory for analysis. This monitoring allows the assessment of the hydric body to be made in sectors that take account of the local dynamics, while the continuous monitoring is carried out by a multiparametric probe located in the center of the Lagoon (LRF3). This allows variations in the quality of the water to be followed in real time and thus rapid action to be taken in the event of situations of imbalance (**Figures 2** and **3**). Every 30 seconds, the probe transmits the measurements to a database made available for the SMAC. The distribution of the collection stations of the Rodrigo de Freitas Lagoon are designed to gather samples of the three sectors established by the Municipal Decree 18.415/2000, in a representative way. Area 1 depends on four sampling points: LRF1, LRF2, LRF3, and LRF5, according to **Figure 4**. Area 2 has point LRF4, and area 3 has point LRF6. All the points were georeferenced by using the UTM coordi-

In addition to the water of the Lagoon, the water from the rivers of Macacos and Cabeca was also assessed, together with the canals of General Garzon, the Jockey Club (the stretch of the Visconde de Albuquerque Canal which passes by the Jockey Club of the Lagoon), and the Jardim de Alah. One meteorological station, installed at the Rowing Stadium of the Lagoon is responsible for continuously monitoring the climatic conditions of the local region and sending the information to a database

Some parameters are monitored in the LRF in both a precise and continuous

way, such as is the case with dissolved oxygen, turbidity, salinity, and pH.

As well as the bulletins, flags are hoisted on masts that are located in the Parques dos Patins e Pedalinhos (parks for roller skates and paddle boats). Information is provided on the conditions related to the protection of aquatic communities: green flag (balanced state), conditions suitable for an aquatic life; yellow flag (state of alert), conditions of imbalance, which if aggravated, can adversely affect the survival of the aquatic community; and red flag (critical state), unsuitable conditions

*DOI: http://dx.doi.org/10.5772/intechopen.88687*

**3.2 Monitoring carried out by TECMA**

and the discharging of effluents into its waters.

nates and are shown in **Table 4**.

*3.2.1 Sampling stations and the monitoring parameters*

the clients (SMAC).

the hydric body [11].

for aquatic life which can lead to the mass death of the fish.

*Environmental Monitoring of Water Quality as a Planning and Management Tool: A Case… DOI: http://dx.doi.org/10.5772/intechopen.88687*

As well as the bulletins, flags are hoisted on masts that are located in the Parques dos Patins e Pedalinhos (parks for roller skates and paddle boats). Information is provided on the conditions related to the protection of aquatic communities: green flag (balanced state), conditions suitable for an aquatic life; yellow flag (state of alert), conditions of imbalance, which if aggravated, can adversely affect the survival of the aquatic community; and red flag (critical state), unsuitable conditions for aquatic life which can lead to the mass death of the fish.

The control of the quality of the water in the LRF has been carried out by TECMA since 2011, through a contract for undertaking services that include data collection, analyses, making results available, and drawing up periodical reports for the clients (SMAC).

## **3.2 Monitoring carried out by TECMA**

*Lagoon Environments Around the World - A Scientific Perspective*

techno-administrative, financial, and political standpoint.

inspected and monitored water bodies in the country.

**3.1 General considerations**

anthropic interferences.

strategic sectors of municipal planning such as sanitation and housing.

concern to maintain its level at around 0.40 m, as a preventive measure to reduce the risk of flooding (since events of this kind have been growing in intensity and frequency) which can cause serious damage and immense suffering to the public. According to Ricci and Medeiros [24], the implementation of policies involving water resources in the basin of the Rodrigo de Freitas Lagoon is still in its early stages. This is because it requires an active attempt to design tools linked to planning, as well as to encourage the strengthening of bodies attached to the Management System of Water Resources. This particularly applies to the planning of activities and the gradual integration of the bodies that already play a role in this area. Ricci and Medeiros [24] argue that the structure created through the cooperative agreement between the State and municipality for the management of the hydrographic basin of the Rodrigo de Freitas Lagoon has become a proof of the considerable importance attached to the management of water resources, since it includes, as an essential prerequisite, the presence of the municipal authorities in the area of management and requires the structuring of municipal power from a

These authors recommend that municipal power should be exercised in three fronts to ensure the underlying assumptions about the necessary policies for water resources are made effective: (1) a strengthening of the Management System of Water Resources, in particular, the Committee for the Integration of the Hydric Basin and the Advisory Board; (2) an effective and integrated application of the management tools for water resources; (3) the integration of policies for water resources and other

It is worth underlining that as a result of the recognized importance of the Lagoon among the people of Rio and the fact that it was a site for Olympic Games competitions in 2016, the LRF has ended up becoming one of the most closely

**3. Environmental monitoring and the quality of the water of LRF**

It is not only owing to its environmental importance but also because of its economic, social, and touristic value that the quality of the waters of the Rodrigo de Freitas Lagoon is the object of constant research projects that seek its improvement. The basic aim of the program called the "Assessment of the Quality of Water in the Rodrigo de Freitas Lagoon and the Rivers and Canals" attached to it is to examine the environmental management of the system formed by its water bodies. Its scope covers the obtaining of environmental information in real time, combined with services for the collection of samples and physicochemical and biological analyses to form a database that can allow an investigation to be carried out of the quality of the water of the Lagoon in the face of natural and

Bulletins are issued on the "Quality of the Water in the Lagoon" on a daily basis, and these provide information about the condition of the water with regard to protecting the aquatic communities and making a secondary contact classification (i.e., "appropriate" or "inappropriate"); these are then published in the bulletins from the Center of Operations of the City Council (COR) and also in the Portal of the Council. In the case of the classification of secondary contacts, a limit for the density of 2000 NMP/100 ml of *Escherichia coli* was established for at least 80% of the six samples collected for each of the three areas established in the Municipal Decree 18.415/2000, in accordance with the methodology employed by CONAMA 357/2005.

**32**

The main purpose of the current monitoring which depends on specific and continuous collections is to follow the physical, chemical, and biological alterations resulting from anthropic activities. It also examines the natural phenomena which can impair the quality of the water both for the protection of aquatic communities and for sporting activities in secondary contact and thus recommends what necessary measures should be taken to maintain the quality of the water of the hydric body [11].

The Lagoon requires constant monitoring since it is a naturally vulnerable system that is subject to natural phenomena like stagnation and the deterioration of the quality of the water, the emission of gases, silting, and the high mortality rate of fish [9]. These kinds of problems can be aggravated further by intense urbanization and the discharging of effluents into its waters.

#### *3.2.1 Sampling stations and the monitoring parameters*

The specific monitoring of the Lagoon is carried out in six sampling stations, codified from LRF1 to LRF6, with collections being made twice a week by means of portable field equipment and then sent to the laboratory for analysis. This monitoring allows the assessment of the hydric body to be made in sectors that take account of the local dynamics, while the continuous monitoring is carried out by a multiparametric probe located in the center of the Lagoon (LRF3). This allows variations in the quality of the water to be followed in real time and thus rapid action to be taken in the event of situations of imbalance (**Figures 2** and **3**). Every 30 seconds, the probe transmits the measurements to a database made available for the SMAC.

The distribution of the collection stations of the Rodrigo de Freitas Lagoon are designed to gather samples of the three sectors established by the Municipal Decree 18.415/2000, in a representative way. Area 1 depends on four sampling points: LRF1, LRF2, LRF3, and LRF5, according to **Figure 4**. Area 2 has point LRF4, and area 3 has point LRF6. All the points were georeferenced by using the UTM coordinates and are shown in **Table 4**.

In addition to the water of the Lagoon, the water from the rivers of Macacos and Cabeca was also assessed, together with the canals of General Garzon, the Jockey Club (the stretch of the Visconde de Albuquerque Canal which passes by the Jockey Club of the Lagoon), and the Jardim de Alah. One meteorological station, installed at the Rowing Stadium of the Lagoon is responsible for continuously monitoring the climatic conditions of the local region and sending the information to a database every 15 minutes.

Some parameters are monitored in the LRF in both a precise and continuous way, such as is the case with dissolved oxygen, turbidity, salinity, and pH.

**Figure 2.** *Portable equipment involved in the precise monitoring.*

#### **Figure 3.**

*Buoy containing the multiparametric probe multiparamétrica. (Source: Photos supplied by the TECMA, 2016).*

The specific monitoring still depends on measurements of ammonia nitrogen, total phosphorus, orthophosphate, nitrate, silica, total coliforms, *Escherichia coli*, and the phytoplankton community. There is still continuous monitoring of the chlorophyll parameter a.

In times of drought, technicians from the RIOAGUAS Foundation carried out daily inspections at the points of the rainwater drains where wastewater was directly discharged into the Lagoon or the Jardim de Alah Canal, for the detection of *Nessler* effluent reagents (through a qualitative test for the presence of ammonia which is indicative of recent drainage). However, it was found that, owing to the

**35**

**Figure 4.**

**Table 4.**

*Environmental Monitoring of Water Quality as a Planning and Management Tool: A Case…*

delay in the renewal of the contract between the RIOAGUAS and the company that rendered the operational service for operating the floodgates of the canals linked to the LRF, there was a suspension of the activities required for managing these devices. Added to this, there was an interruption of the desludging, as well as the inspections and conveying of information about the water features and fishing, in

**Collection stations Location (UTM coordinates)**

LRF1 683289 7459128 LRF2 683910 7459151 LRF3 683250 7458571 LRF4 684117 7458011 LRF5 683023 7457937 LRF6 683898 7457684

**X Y**

On the basis of an assessment of the history of the monitoring and through a comparison of the points that were analyzed, it was found that even after the interventions carried out by the policymakers, with the aim of eradicating the effects of effluents, some areas of the Lagoon still had unsuitable environmental conditions with parameters of a quality below what was recommended, as is shown in **Table 5**

the period from November 26 to December 3, 2018.

*Coordinates for the collection stations of the Rodrigo de Freitas Lagoon [8].*

*Location of the collection stations of the Rodrigo de Freitas Lagoon [8].*

which refers to data obtained from six monitoring points.

*3.2.2 Monitoring data assessment*

*DOI: http://dx.doi.org/10.5772/intechopen.88687*

*Environmental Monitoring of Water Quality as a Planning and Management Tool: A Case… DOI: http://dx.doi.org/10.5772/intechopen.88687*

#### **Figure 4.**

*Lagoon Environments Around the World - A Scientific Perspective*

**34**

**Figure 3.**

**Figure 2.**

*Portable equipment involved in the precise monitoring.*

parameter a.

*Buoy containing the multiparametric probe multiparamétrica. (Source: Photos supplied by the TECMA, 2016).*

The specific monitoring still depends on measurements of ammonia nitrogen, total phosphorus, orthophosphate, nitrate, silica, total coliforms, *Escherichia coli*, and the phytoplankton community. There is still continuous monitoring of the chlorophyll

In times of drought, technicians from the RIOAGUAS Foundation carried out daily inspections at the points of the rainwater drains where wastewater was directly discharged into the Lagoon or the Jardim de Alah Canal, for the detection of *Nessler* effluent reagents (through a qualitative test for the presence of ammonia which is indicative of recent drainage). However, it was found that, owing to the

*Location of the collection stations of the Rodrigo de Freitas Lagoon [8].*


#### **Table 4.**

*Coordinates for the collection stations of the Rodrigo de Freitas Lagoon [8].*

delay in the renewal of the contract between the RIOAGUAS and the company that rendered the operational service for operating the floodgates of the canals linked to the LRF, there was a suspension of the activities required for managing these devices. Added to this, there was an interruption of the desludging, as well as the inspections and conveying of information about the water features and fishing, in the period from November 26 to December 3, 2018.

### *3.2.2 Monitoring data assessment*

On the basis of an assessment of the history of the monitoring and through a comparison of the points that were analyzed, it was found that even after the interventions carried out by the policymakers, with the aim of eradicating the effects of effluents, some areas of the Lagoon still had unsuitable environmental conditions with parameters of a quality below what was recommended, as is shown in **Table 5** which refers to data obtained from six monitoring points.


**37**

**pH**

**Temperature (°C)**

**Salinity of** **Averages of the results for the parameters at the monitoring points—Spring 2016 (Period 22/09 to 21/12)**

LRF1 LRF2 LRF3 LRF4 LRF5 LRF6 Averages Standard Deviation

**Table 5.**

8.3 0.0

0.1

0.0

0.2 *Comparison of the parameters analyzed in the spring season of 2014, 2015, and 2016 [25] (Note: change all the fractions, e.g., 0.1 > 0.1).*

0.3

6.8

139

0.010

0.002

0.000

26.6

16.6

7.0

5.3

122.4

168

0.166

0.036

0.016

8.3

26.6

16.6

6.9

5.2

113.6

255

0.172

0.037

0.016

8.3

26.7

16.6

6.9

5.3

115.0

180

0.181

0.034

0.016

8.3

26.6

16.6

7.0

5.2

122.2

78

0.151

0.036

0.016

8.4

26.6

16.6

7.1

4.9

127.5

38

0.160

0.040

0.016

8.4

26.6

16.6

7.1

5.5

130.3

398

0.161

0.037

0.016

8.3

26.6

16.5

7.4

5.7

125.8

61

0.170

0.033

0.016

**OD (mg/L)**

**Turbidity (NTU)**

**Secchi Disc (cm)**

*E. coli* **(NMP/100 mL)**

**Nitrogen ammonia (mg/L)**

**Total phosphorus (mg/L)**

**Total phosphate (mg/L)**

*Environmental Monitoring of Water Quality as a Planning and Management Tool: A Case…*

*DOI: http://dx.doi.org/10.5772/intechopen.88687*


**Table 5.** *Comparison of the parameters analyzed in the spring season of 2014, 2015, and 2016 [25] (Note: change all the fractions, e.g., 0.1 > 0.1).*
