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LAGUNA LAKE DEVELOPMENT AUTHORITY Resource Management and Development Department

Environmental Laboratory and Research Division

Water Quality Assessment Report

Tanay River 2011

WATER QUALITY ASSESSMENT REPORT

TANAY RIVER

2011

Prepared by:

Jonathan U. Nicolas – Aquaculturist II

Christine S. Garcia – Environmental Management Specialist II

Ma. Magdalena T. Almonte – Environmental Management Specialist II

Usman Datu F. Mamadra Jr. – Environmental Management Specialist I

Reviewed by:

Jocelyn G. Sta. Ana – OIC, Environmental Laboratory and Research Division

Adelina C. Santos-Borja – OIC, Resource Management and Development Department

For more information, please contact:


Resource Management and Development Department

Laguna Lake Development Authority

Tel No. 286-61-43

Figure 1. Location of Tanay River Sampling Stations.

Stn. 1 – Mouth of Tanay River at Brgy. Wawa. Stn. 2 – Town Proper (Poblacion) Plaza Aldea Stn. 3 – Manila East Road Bridge (National High-way) Stn. 4 – Headwater located near the entrance of Daranak National Park Stn. 5 – Daranak Falls

Introduction :

The Municipality of Tanay is a 1st class municipality in the province of Rizal, Philippines.

It is located 57 kilometers east of Manila, although a typical commute between Manila and

Tanay will take between one to three hours depending upon traffic conditions. It contains

portions of the Sierra Madre Mountains and is bordered by Antipolo City in the northeast,

Baras, Morong and Teresa in the west, General Nakar (Quezon Province) in the east, and

Pililla, Santa Maria (Laguna province) as well as the Laguna de Bay in the south.

According to the latest census (2007), it has a population of 94,460 people in 15,720

households. The majority of the population consists of Tagalogs who live near Laguna de

Bay, though there is also a significant percentage of mountain dwelling people living in the

northern portions of the municipality. (www.tanay.gov.ph)

Tanay municipality has strong hilly to mountainous areas (30 degrees and above) with an

expanse of approximately 4,188 hectares. These are found covering portions of Barangay

Sta. Inez, Mamuyao, Tinukan, Sto. Nino, San Andres, Cayabu, Laiban, Daraitan and

Sampaloc. Strong sloping or strongly rolling land (18-30 degrees) which are found in

portions of Barangays Plaza Aldea, Kaybuto, Katipunan Bayani, Tabing Ilog, Mag-ampon,

Cuyambay, Sampaloc, Daraitan, Laiban, Mamuyao, Sto. Nino, Tinukan, and San Andres

accounts for 8,471 hectares of the total land area. Moderately sloping or rolling land (8-18

degrees) constitutes 3,100 hectares of the municipality’s total land area. These are found

in Barangays Cayabu, San Andres, Cuyambay, Sampaloc, Plaza Aldea, Daraitan, Laiban,

Tandang Kutyo and Katipunan Bayani. The remaining 7,807 hectares have slopes ranging

from level to undulating. Maximum rainfall usually occurs from June to September. The

average rainfall is 135.5 mm with a peak of 322.2 mm in August and a low 5.3 mm in

April. Relative humidity is 79%. This makes the municipality better than the municipalities

of Laguna, which has an average relative humidity of 81%. Portions of Barangays Kay

Buto, San Isidro, Pinagkamaligan, Plaza Aldea, and the whole of Wawa are affected by

moderate to severe seasonal flooding hazard characterized by more frequent and deeper

run-off water. This takes a week or a few months to subside. Based on the land limitation

map, eroded areas comprise about 749 hectares while erosion-prone shallow soil areas

consist of 1,855 hectares.(R.Vicente et.al, 2010)

In support of the River Rehabilitation Program of LLDA, the Environmental Laboratory

and Research Division (ELRD) staff conducted water quality sampling in Tanay River on

June 19, 2011, to represent the wet season and December 1, 2011, to represent the dry

season.

http://en.wikipedia.org/wiki/Philippine_municipality

http://en.wikipedia.org/wiki/Philippine_province

http://en.wikipedia.org/wiki/Rizal_province

http://en.wikipedia.org/wiki/Philippines

http://en.wikipedia.org/wiki/Manila

http://en.wikipedia.org/wiki/Sierra_Madre_%28Philippines%29

http://en.wikipedia.org/wiki/Antipolo_City

http://en.wikipedia.org/wiki/Baras,_Rizal

http://en.wikipedia.org/wiki/Morong,_Rizal

http://en.wikipedia.org/wiki/Teresa,_Rizal

http://en.wikipedia.org/wiki/General_Nakar,_Quezon

http://en.wikipedia.org/wiki/Quezon

http://en.wikipedia.org/wiki/Pililla,_Rizal

http://en.wikipedia.org/wiki/Santa_Maria,_Laguna

http://en.wikipedia.org/wiki/Laguna_province

http://en.wikipedia.org/wiki/Laguna_de_Bay

Water Quality Assessment Report –Tanay River


Laguna Lake Development Authority 2

Sampling Stations and Frequency of Sampling:

Monitoring was undertaken on a seasonal basis (wet and dry). Collection of water and

sediment samples for physico-chemical, biological and microbiological analyses was

conducted at the different designated stations identified during the reconnaissance activity

on 17 June 2011 along the stretch of Tanay River. ELRD has established five (5)

sampling stations at various sections of the river and were properly marked using a Global

Positioning System (GPS) device. Sampling stations were named and identified as

follows: Station 1 – Mouth of Tanay River at Barangay Wawa; Station 2 – Plaza Aldea,

Poblacion, beside the Barangay Hall; Station 3 – Manila East Road, National Hi-way;

Station 4 – Headwater, near the entrance of Daranak National Park and Station 5 –

Daranak Falls. The map of the sampling stations is shown in Figure 1.

The assessment of the water quality was done for the purpose of determining the seasonal

variations of the water quality at different stations of the river in terms of the chemical,

biological and bacteriological parameters.

Field Observations and In-Situ Measurements:

Field observations were recorded during the sampling activities for both wet and dry

seasons and are presented in Tables 2 and 3. During the wet season, moderate to fast

flowing waters were observed with water temperature ranging from 26oC to 28

oC. A

sunny weather occurred at the time of sampling. Air temperature was recorded between

27oC to 31

oC. Dry season registered a lower level of temperature for both water and air

that ranges from 26oC to 29

oC for air and 23

oC to 25

oC for water. Sunny weather and

moderate to fast flowing waters was observed at the time of sampling.

Actual physical condition of all the stations for wet and dry seasons is presented in Figures

2a to 6b.




Stn. 1 – Mouth of Tanay River at Brgy. Wawa.

Stn. 2 – Town Proper (Poblacion) Plaza Aldea

Stn. 3 – Manila East Road Bridge (National High-way)

Stn. 4 – Headwater located near the entrance of Daranak National Park

Stn. 5 – Daranak Falls Figure 1. Location of Tanay River Sampling Stations.




Figure 2a. Tanay River Station 1

Wet Season – June 29, 2011

Field Observations and in-Situ Measurements

Name of Station Mouth – Brgy. Wawa

GPS Reading (UTM)

P0315034

1602589

Time 09:35 AM

Air Temperature (oC) 27

Water Temperature (oC) 26

Weather Sunny

Water Condition Moderately flowing

Color of the Water Greenish

Width Approximately 40m

Depth 1.5m

Other observations: Presence of fish fry along the side,

patches of water hyacinth going to

the lake, floating debris and dried

twigs, residential area




Figure 2b. Tanay River Station 1

Dry Season - December 1, 2011


Name of Station Mouth – Brgy. Wawa

GPS Reading (UTM)

P0315034

1602589

Time 09:15 AM



Weather Sunny


Color of the Water Greenish brown


Depth .75m

Other observations: With floating garbage







Name of Station

Town Proper, Poblacion (Plaza

Aldea)

GPS Reading (UTM)

P0315160

1603451

Time 09:40 AM



Weather Sunny




Depth .75m

Other observations: residential and commercial area,

with floating debris, presence of

fish fry, soil erosion brought by

heavy flushing







Name of Station

Town Proper, Poblacion (Plaza

Aldea)

GPS Reading (UTM)

P0315160

1603451

Time 09:25 AM



Weather Sunny



With Approximately 24m

Depth .5m

Other observations: With floating debris, low level of

water







Name of Station

Manila East Road

(National High-way)

GPS Reading (UTM)

P0315920

1604051

Time 10:00 AM



Weather Sunny

Water Condition Fast flowing



Depth .75m

Other observations: Residential and commercial area,

pebbles to head size stones river

bed, grasses/cogon on both sides

of the banks, presence of garbage

also noted







Name of Station

Manila East Road

(National High-way)

GPS Reading (UTM)

P0315920

1604051

Time 10:20 AM



Weather Sunny


Color of the Water Clear


Depth .3m

Other observations: Presence of garbage along the

banks







Name of Station

Headwater (near entrance of

Daranak National Park)

GPS Reading (UTM)

P031781

1608658

Time 10:58 AM



Weather Sunny




Depth .3m

Other observations: Presence of few garbage result of

picnic activity, floating

debris/twigs, pebbles to head size

stones river bed, area for

swimming







Name of Station

Headwater (near entrance of

Daranak National Park)

GPS Reading (UTM)

P031781

1608658

Time 10:35 AM



Weather Sunny




Depth .2m

Other observations: Rock balancing activity was noted

in the area







Name of Station Daranak Falls

GPS Reading (UTM)

P0317865

1608629

Time 10:48 AM



Weather sunny




Depth .75m

Other observations: Trees on both sides of the river

banks forming shaded areas, dried

leaves/twigs floating, pebbles to

headsize stones river







Name of Station Daranak Falls

GPS Reading (UTM)

P0317865

1608629

Time 11:50 AM



Weather Sunny




Depth .5m

Other observations: Rock balancing activity was noted

in the area




Results of Physico-Chemical Analyses:

The results of the physico-chemical analyses of the collected water samples are

summarized in Tables 1 and 2. The analytical results were compared to the DENR

Water Quality Criteria for Class C Waters as specified in the DENR Administrative

Order (DAO) No. 34 and below are the findings:

Dissolved Oxygen

Dissolved Oxygen (Wet/Dry)

0

2

4

6

8

10

Brg

y. W

aw

a

Plaza A

ldea

Manila E

ast

Road

Dara

nak Falls

Tanay H

eadw

ater

Stations

D.O

. m

g/L

D.O.- WET

D.O.- DRY

Class "C" (5mg/L

minimum )

Dissolved Oxygen (DO) is one of the water quality parameters used as an indication of

how polluted the water is and how well the water can support aquatic plant and animal

life. DO is the amount of oxygen that is dissolved in water and is essential to streams

and lakes.

For the wet season, the dissolved oxygen in all the stations met the minimum criterion

of 5mg/L for Class C waters. This is an indication that the river system has good

quality for fish and other organisms to survive. Likewise, all stations passed the

criterion for D.O. for the dry season.




Biochemical Oxygen Demand

Biochemical oxygen demand, or BOD, measures the amount of oxygen consumed by

microorganisms in decomposing organic matter in water. BOD parameter measures the

organic strength of wastes in water; the higher the BOD concentration, the greater the

degree of organic pollution.

For Tanay, all five stations passed the criterion of 10 mg/L for BOD during the wet

and dry season.

pH

pH (WeT/Dry)

0

2

4

6

8

Brg

y. W

aw

a

Plaza A

ldea

Manila E

ast

Road

Dara

nak Falls

Tanay H

eadw

ater

Stations

pH

un

it

pH- WET

pH- DRY

Class "C" ( 6.5, unit )

Class "C" ( 8.5, unit )

The most commonly measured chemical characteristic of water is its pH since its

changes can alter the aspects of water chemistry. Most rivers have a neutral to slightly

basic pH of 6.5 to 8.5. If the river has pH less than 5.5, it may be too acidic for fish to

survive in, while river with a pH greater than 8.6 may be too basic. Sudden shift in pH

can affect aquatic life since this may indicate presence of contaminants in the river.

However, since some rivers are naturally acidic — or basic — pH may not necessarily

indicate pollution (www.cotf.edu).

http://www.cotf.edu/




The pH for all the stations in Tanay is within the acceptable range for Class C waters

for the wet season. As for the dry season, the stations in Daranak Falls and Tanay

Headwater with pH values of 8.6 slightly exceeded the required range.

Oil and Grease

The concentration of dispersed oil and grease in water is an important parameter in

water quality. These can cause surface films and shoreline deposits leading to

environmental degradation, which can result to human health risks when discharged to

surface and ground water.

Both stations in Brgy. Wawa and Manila East Road failed to comply with the criterion

for Oil and Grease during the wet season. This may be due to wastes coming from

nearby community. But for the dry season, all stations passed the criterion for oil and

grease.

Nitrate and Inorganic Phosphate

Nitrate (Wet/Dry)

0

2

4

6

8

10

12

Brg

y. W

aw

a

Plaza A

ldea

Manila E

ast

Road

Dara

nak Falls

Tanay H

eadw

ater

Stations

Nit

rate

, m

g-N

/L

Nitrate-WET

Nitrate-DRY

Class "C" (10 mg/L)




Inorganic Phosphate (Wet/Dry)

0

0.1

0.2

0.3

0.4

0.5

Brg

y. W

aw

a

Plaza A

ldea

Manila E

ast

Road

Dara

nak Falls

Tanay H

eadw

ater

Stations

Ino

rgan

ic P

ho

sp

hate

, m

g-P

/L

Inorganic Phosphate-

WET

Inorganic Phosphate-

DRY

Class "C" (0.4 mg/L)

Phosphates and nitrates are required to maintain the growth and metabolism of plants

and animals. However, in excess amounts, these nutrients are proven harmful.

Nutrients enrichment or eutrophication is a main cause in the destruction of bodies of

water. This causes phytoplankton to grow and reproduce more rapidly, resulting in

algal blooms which disrupt normal ecosystem functioning and cause many problems

like depletion of dissolved oxygen, blocking of sunlight from photosynthetic marine

plants and producing toxins that are harmful to higher forms of life (www.water-

pollution.org.uk/eutophica).

All stations passed the criteria for nitrates and phosphates for the wet and dry season.

Chloride

Chloride (Wet/Dry)

0

50

100

150

200

250

300

350

Brg

y. W

aw

a

Plaza A

ldea

Manila E

ast

Road

Dara

nak Falls

Tanay H

eadw

ater

Stations

Ino

rgan

ic P

ho

sp

hate

, m

g-P

/L

Chloride-WET

Chloride-DRY

Class "C" (350 mg/L)

Chlorides are salts resulting from the combination of the gas chlorine with a metal.

Some common chlorides are sodium chloride (NaCl) and magnesium chloride

http://www.water-pollution.org.uk/eutophica

http://www.water-pollution.org.uk/eutophica




(MgCl2). Chlorine which is commonly used as a disinfectant is highly toxic. In

combination with a metal such as sodium it becomes essential for life. Small amounts

of chlorides are required for normal cell functions in plant and animal life. Chlorides

may get into surface water from several sources like rocks containing chlorides;

agricultural runoff; wastewater from industries; oil well wastes; effluent wastewater

from wastewater treatment plants, and road salting. High level of chlorides can

contaminate fresh water streams and lakes wherein fish and aquatic communities

cannot survive. (www.state.ky.us/nrepc/water/ncpel.htm)

All the stations for Tanay showed low concentration of chloride during the wet and dry

season, thus passing the criterion for chloride which is 350 mg/L.




Table 1. Results of the Physico-Chemical Analysis of Water Samples from Tanay River: WET season

PARAMETERS STATIONS DENR Class C Water

Quality Criteria Stn. 1 Stn. 2 Stn. 3 Stn. 4 Stn. 5

pH, units 7.0 7.0 7.1 7.5 7.0 6.5-8.5

Total Suspended Solids, mg/L 15 17 17 9 14 <30 (increase)

Total Dissolved Solids, mg/L 248 253 223 217 211 *

Total Solids, mg.L 263 270 240 226 225 *

Chemical Oxygen Demand, mg/L <4 <4 <4 <4 <4 *

Biochemical Oxygen Demand,

mg/L

3 4 2 <2 2 10

Dissolved Oxygen, mg/L 6.8 7.2 7.3 7.8 8.1 5 (minimum)

Oil/Grease, mg/L 3 2 3 2 1 2

Ammonia, mg/L NH3-N 0.1312 0.1225 0.1598 0.0458 0.0141 *

Nitrate, mg/L NO3-N 0.9510 1.0446 0.8773 0.5057 0.3455 10

Inorganic Phosphate, mg/L 0.3061 0.2740 0.3265 0.0843 0.0044 0.4

Total Phosphorus, mg/L 0.3061 0.277 0.3265 0.1089 0.0216 *

Total Nitrogen, mg/L 3.9 5.6 3.9 4.3 3.2 *

Chloride, mg/L 11 11 11 11 7 350

Alkalinity, mg CaCO3/L 188 180 176 180 172 *

Calcium Hardness, mg CaCO3/L 128 116 112 100 100 *

Total Hardness,mg CaCO3/L 192 188 188 184 168 *

Turbidity, NTU 9 11 9 6 7 *

Conductivity, uS/cm 405 399 385 375 358 *

*Note: No set DENR Class C Water Quality Criteria




Table 2. Results of the Physico-Chemical Analysis of Water Samples from Tanay River: DRY season

PARAMETERS STATIONS DENR Class C Water

Quality Criteria Stn. 1 Stn. 2 Stn. 3 Stn. 4 Stn. 5

pH, units 7.9 8.1 8.4 8.6 8.6 6.5-8.5

Total Suspended Solids, mg/L 4 5 8 10 6 <30 (increase)

Total Dissolved Solids, mg/L 272 284 262 261 226 *

Total Solids, mg.L 276 289 270 271 232 *

Chemical Oxygen Demand, mg/L 8 12 16 16 12 *

Biochemical Oxygen Demand,

mg/L

2 2 <2 <2 <2 10

Dissolved Oxygen, mg/L 5.6 8.2 8.0 8.0 8.1 5 (minimum)

Oil/Grease, mg/L <1 <1 <1 <1 <1 2

Ammonia, mg/L NH3-N 0.2329 0.2626 0.1447 0.1464 0.2031 *

Nitrate, mg/L NO3-N 1.4822 1.662 1.5902 0.4387 0.7227 10

Inorganic Phosphate, mg/L 0.2585 0.2559 0.1876 0.0680 0.0079 0.4

Total Phosphorus, mg/L 0.2585 0.2559 0.1876 0.156 0.2342 *

Total Nitrogen, mg/L 4.6 4.0 3.9 4.5 4.7 *

Chloride, mg/L 11 15 11 15 4 350

Alkalinity, mg CaCO3/L 192 184 184 184 160 *

Calcium Hardness, mg CaCO3/L 120 112 88 116 96 *

Total Hardness,mg CaCO3/L 196 200 208 200 200 *

Turbidity, NTU 2 2 2 2 1 *

Conductivity, uS/cm 366 360 341 335 331 *

*Note: No set DENR Class C Water Quality Criteria




Results of Biological Analyses:

Table 6a to 6d present the algal and benthic population of Tanay River and its water

quality assessment.

Phytoplankton or Microscopic Algae (Dry and Wet Season)

Phytoplankton also known as microalgae, are similar to terrestrial plants that contain

chlorophyll and requires sunlight in order to live and grow. Most phytoplankton are

buoyant and occupies the upper portion of the water column where sunlight

penetrates the water and requires inorganic nutrients such as nitrates, phosphates, and

sulfur which in effect are converted into proteins, fats, and carbohydrates.

In a balanced ecosystem, phytoplankton provides food for a wide range of aquatic life

including fish, shrimps and snails. When too many nutrients are available,

phytoplankton may grow out of control and form harmful algal blooms (HABs). These

blooms can produce extremely toxic compounds that have harmful effects on fish,

shellfish, mammals, birds, and even to people.

Phytoplankton is also considered as water quality indicator of an ecosystem such as

lakes and rivers. Phytoplankton communities are sensitive to changes in their

environment and, therefore, phytoplankton total biomass and many phytoplankton

species are used as indicators of water quality (e. g. Olrik, 1994; Reynolds et al., 2002;

Brettum and Andersen, 2005).

Based on the results of quantitative and qualitative analysis of phytoplankton samples

collected in Tanay River during the dry season, three (3) stations were classified as

polluted in terms of algal composition and percentage contribution. Stations 2, 3 and 5

gave a total of 3171, 45784 and 1364 counts per ml of polluted algae identified as

Nitzchia sp.and Gomphonema sp. with percent contribution of 75, 90.6 and 50

respectively. Station 5 was also classified as polluted water with only 50% algal

contribution from polluted water indicator since 50% from unclassified algae was

identified. However, only station 4 (Headwater) was classified as clean water based on

the algal composition identified as Navicula sp. Station 1 was dominated by

Glenodinium sp. with total counts of 1110 per ml. It was however observed that based

on the water quality condition during the wet season, no significant difference was

recorded in the stretch of Tanay River.. It is worth mentioning that Station 4

maintained its classification as clean water. The algal population is mainly clean water

indicator. Stations 1,2,3 and 5 were all classified as polluted waters since polluted

water indicators dominate the algal population. Nitzchia sp. was the only algae

recorded in Stations 2 and 5 as compared to only 75 and 50 percent in same stations

during the dry season, respectively.

Benthic Fauna (Dry and Wet Season)

Benthic fauna are organisms that dwell in the bottom of any water body. Tanay River

was classified according to the benthic populations as Clean Water Indicator (CWI),

Moderately Polluted Indicator (MPWI), and Polluted Water Indicator (PWI).




During the dry season, Station 1 was relatively the most diversified with five (5)

species identified with a total of 808 counts per liter with Physa gyrina as the most

dominant. Station 1 was classified as polluted with 82.30 percent of the population

belonging to the Polluted Water Indicator. Station 2 was classified as moderately

polluted with 100 percent moderately polluted benthic indicators with Melonoides

tuberculatus as the dominant species. Station 3, 4 and 5 were classified as clean water

with 75, 100 and 100 percent clean water indicator identified respectively with Caenis

sp and Baetis sp as the dominant species.

Likewise, during the wet season it was observed that Station 1 has improved its water

quality from polluted to moderately polluted based on the identified benthic fauna

population .Stations 2,3,4 and 5 maintained its classifications as moderately polluted

and as clean water, respectively. In terms of water quality, Tanay River has shown a

little bit of improvement especially in Station 1 from polluted during the dry season to

moderately polluted during the wet season.

Table 3. Results of Biological Analyses of Water Samples

3a. Summary of Water Quality Assessment in Tanay River Based on

Phytoplankton/Algal Population

Wet Season

Stations Location Counts (organism/sq.m.) % Contribution Water Quality

Assessment

CWA PWA OTHER

S TOTAL %

CWA %

PWA % OTHERS

1 Mouth, Brgy. Wawa 718 2153 0 2871 25.0 75.0 0.0 Polluted

2 Plaza Aldea 0 789 0 789 0.0 100.0 0.0 Polluted

3 Manila East Road 2153 2871 0 5024 42.9 57.1 0.0 Polluted

4 Headwater 753 0 0 753 100.0 0.0 0.0 Clean

5 Daranak Falls 0 861 0 861 0.0 100.0 0.0 Polluted

Dry Season

Stations Location Counts (organism/sq.m.) % Contribution Water Quality

Assessment

CWA PWA OTHER

S TOTAL %

CWA %

PWA % OTHERS

1 Mouth, Brgy. Wawa 0 0 1110 1110 0.0 0.0 100.0 Not Classified

2 Plaza Aldea 1057 3171 0 4228 25.0 75.0 0.0 Polluted

3 Manila East Road 2368 45784 2368 50520 4.7 90.6 4.7 Polluted

4 Headwater 2153 0 718 2871 75.0 0.0 25.0 Clean

5 Daranak Falls 0 1364 1364 2728 0.0 50.0 50.0 Polluted

Notes:

CWA - Clean Water Algae

PWA - Polluted Water Algae

Others - Algae not classified as CWA or PWA




3b. Qualitative and Quantitative Analysis of Phytoplankton or Algae

Wet Season

Phytoplankton/Algae Identified

(counts/sq.m.)

Sampling Stations

Stn. 1 Stn. 2 Stn. 3 Stn. 4 Stn. 5

Clean Water Indicator

Division Bacillariophyta

Navicula sp. 718 0 2153 783 0

Sub Total 718 0 2153 783 0

Polluted Water Indicator


Nitzschia sp. 2153 789 2871 0 861

Sub Total 2153 789 2871 0 861

TOTAL 2871 789 5024 783 861

Dry Season

Phytoplankton/Algae Identified

(counts/sq.m.)

Sampling Stations


Clean Water Indicator


Navicula sp. 0 1057 2368 2153 0

Sub Total 0 1057 2368 2153 0

Polluted Water Indicator

Division Cyanophyta

Spirogyra sp. 0 1057 0 0 0


Gomphonema sp. 0 1057 2368 0 0

Nitzschia sp. 0 1057 43416 0 1364

Sub Total 0 3171 45784 0 1364


Stephanodiscus sp. 1110 0 1579 0 0

Synedra sp. 0 0 789 0 682

Division Pyrrophyta

Glenodinium sp. 0 0 0 718 682

Sub Total 1110 0 2368 718 1364

TOTAL 1110 4228 50520 2871 2728

Note: Number of algae is expressed in organism per square meter.




3c. Summary of Water Quality Assessment in Tanay River Based on Benthic

Population

Wet Season

Station Counts % Contribution Water Quality Assessment

CWI MPWI PWI Total %CWI %MPWI %PWI

Stn. 1 0 286 0 286 0 100 0 Moderately

Polluted

Stn. 2 0 334 48 382 0 87.43 12.57 Moderately

Polluted

Stn. 3 33 0 11 44 75 0 25 Clean

Stn. 4 99 0 0 99 100 0 0 Clean

Stn. 5 55 0 0 55 100 0 0 Clean

Dry Season

Station Counts % Contribution Water Quality Assessment

CWI MPWI PWI Total %CWI %MPWI %PWI

Stn. 1 0 143 665 808 0 17.70 82.30 Polluted

Stn. 2 0 381 0 381 0 100 0 Moderately

Polluted

Stn. 3 22 0 11 33 75 0 25 Clean

Stn. 4 77 0 0 77 100 0 0 Clean

Stn. 5 55 0 0 55 100 0 0 Clean

Notes:

Stn. 1 - Tanay River mouth

Stn. 2 - Plaza Aldea, Tanay, Rizal

Stn. 3 - Manila East Road (National Hi-way)

Stn. 4 - Headwater (near entrance of Daranak National Park)

Stn. 5 - Daranak Falls

CWI - Clean Water Indicator

MPWI - Moderately Polluted Water Indicator

PWI - Polluted Water Indicator




3d. Qualitative and Quantitative of Benthic Fauna

Wet Season

Organisms

(# of individual/sq.m.)

Sampling Stations


Clean Water Indicator (CWI)

Order Ephemeroptera

Family Baetidae

Baetis sp. 33 33

Family Caenidae

Caenis sp. 22

Order Plecoptera

Family Perlidae 33 22

Order Hemiptera

Family Gerridae 44 22

TOTAL CWI 33 99 77

Moderately Polluted Indicator (MPWI)

Class Gastropoda

Family Thiaridae

Melanoides tuberculatus 48 48

Thiara sp. 95 190

Family Viviparidae

Viviparus viviparous 143 48

Family Planorbidae

Hippeutis umbilicalis 48

TOTAL MPWI 286 334

Polluted Water Indicator (PWI)

Class Gastropoda

Family Physidae

Physa gyrina 48

Class Insecta

Order Diptera

Family Chironomidae

Diamesa sp. 11

TOTAL PWI 48 11




Dry Season

Organisms

(# of individual/sq.m)

Sampling Stations


Clean Water Indicator (CWI)

Order Ephemeroptera

Family Baetidae

Baetis sp. 22 22 33

Family Caenidae

Caenis sp. 33

Order Trichoptera

Family Hydropsychidae

Hydropsyche 22

Order Hemiptera

Family Gerridae 22

TOTAL CWI 22 77 55

Moderately Polluted Indicator (MPWI)

Class Gastropoda

Family Thiaridae

Thiara scabra 95

Melanoides tuberculatus 95 143

Thiara sp.

Family Planorbidae

Hippeutis umbilicalis 48 48

Family Pleuroceridae

Brotia costulata 95

TOTAL MPWI 143 381

Polluted Water Indicator (PWI)

Class Gastropoda

Family Physidae

Physa gyrina 285

Class Insecta

Order Diptera

Family Chironomidae

Diamesa sp 237 11

Class Oligochaeta

Family Tubificidae 143

TOTAL PWI 665 11

Note: Results of quantitative analysis is expressed in number of individuals per square meter.




Table 4. Results of Bacteriological Analyses of Water Samples

Wet Season

Parameters Stn. 1 Stn. 2 Stn. 3 Stn. 4 Stn. 5

Total Coliform

(MPN/100 ml) 110,000 30,000 5,000 5,000 2,200

Fecal Coliform

(MPN/100 ml) 50,000 23,000 5,000 5,000 1,700

Detection of

Escherichia coli + + + + +

Dry Season

Parameters Stn. 1 Stn. 2 Stn. 3 Stn. 4 Stn. 5

Total Coliform

(MPN/100 ml) 350,000 540,000 92,000 35,000 35,000

Fecal Coliform

(MPN/100 ml) 110,000 240,000 24,000 1,300 35,000

Detection of

Escherichia coli + + - + +

Note: DAO 34, DENR 1990 Class C Water Quality Criterion for Total Coliforms (TC) is 5,000

MPN/100 ml while none for fecal coliforms

Results of Bacteriological Analyses:

0

20,000

40,000

60,000

80,000

100,000

120,000

1 2 3 4 5

MP

N/1

00

mL

Stations

Wet

Dry

WQ Criteria (TC=5000 MPN/100 mL)

350 540




The results of the microbiological analysis of Tanay River is presented in Table 4.

Water quality assessment for microbiological parameters is based on the Water Quality

Criteria for Class C Waters (DAO 34, 1900) which is set at 5,000 MPN/100 mL.

Based on the results, Stations 1 and 2 exceeded the criterion during the wet season.

Station 1which is located within the residential area wherein the domestic wastes are

discharged directly to the river registered the highest total coliform concentration of

110,000 MPN/100 mL, while station 2 is located in the town proper and within the

residential area also. Station 5 gave the lowest coliform concentration of 2,200

MPN/100 mL. It is located in Daranak Falls, whereby less visitors are coming during

the wet season.

During the dry season, all stations exceeded the set criterion. Station 2 recorded the

highest total coliform with the concentration of 540,000 MPN/100 mL while stations 4

and 5 recorded the lowest both at 35,000 MPN/100 mL. Higher concentration was

recorded during the dry season due to low level of water ( 0.3 m for station 4 and 0.5

m for station 5) occurring due to occasional rains and coliform bacteria are

concentrated during summer.

There is no set criterion for fecal coliforms. Station 1 recorded the highest (50,000

MPN/100 mL) while Station 5 recorded the lowest (1,700 MPN/100 mL) during the

wet season. In the dry season, Station 2 recorded the highest concentration at 240,000

MPN/100 mL while Station 4 recorded the lowest concentration of 1,300 MPN/100

mL for the dry season. Escherichia coli is present in all the stations in both wet and

dry season except in Station 3 in the dry season.

Coliforms are class of bacteria found in our environment, including the feces of man

and other warm-blooded animals. Coliform bacteria are commonly used

as bacterial indicator of water since their presence in water may indicate the possible

presence of harmful, disease-causing organisms. Fecal coliforms are the group of the

total coliforms that are considered to be present specifically in the gut and feces of

warm-blooded animals. Because the origin of fecal coliforms are more specific than the

origin of the more general total coliform group of bacteria, fecal coliforms are

considered a more accurate indication of animal or human waste than the total

coliforms. Escherichia coli (E. coli) is the major species in the fecal coliform group. E.

coli is considered to be the species of coliform bacteria that is the best indicator of

fecal pollution and on the possible presence of pathogens (Standard Methods for the

Examination of Water and Wastewater, 21st ed.)

Conclusion and Recommendations:

Based on the results of the chemical analyses, only Station 1 (Brgy. Wawa) and Station

3 (Manila East Road, National Highway) representing the wet season failed to meet

the water quality criterion set in the Department of Environment and Natural

Resources (DENR) Administrative Order (DAO) 34 in terms of oil and grease with a

measured value of 3 mg/L. All other remaining stations passed the criteria. Water

quality assessment based on the result of biological parameter showed that only station

4 (Headwater) recorded as clean for both wet and dry season. Stations 1, 2, 3 and 5

appeared to be polluted in terms of algal counts and moderately polluted in benthic




population. However, Station 5 (Daranak falls) also indicates clean water in terms of

its invertebrates community. Among the five (5) stations identified along the stretch of

Tanay river, Station 5 (Daranak falls) during the wet season was able to comply with

the DAO water quality criterion for Total Coliform with a recorded value of 2,200

MPN/100 mL . All other stations failed to meet the set criterion.

With the presented results based on chemical, biological and microbiological analysis,

Stations 4 and 5 are considered to be clean though Station 5 (wet season) gave an

indication of pollution in terms of phytoplankton analysis. This could be attributed to

the improper use of the Daranak resort. This is an indication that the river system of

Tanay needs to be addressed for a restoration program.

In order to save the deteriorating water quality in some part of Tanay River, it is

strongly recommended that continuous effort to clean up the river must be done

devotedly not only by LLDA and Local Government Unit but also by the community.

Indiscriminate dumping of garbage from the people living along the river banks must

be given strict compliance with corresponding penalties.

Information/Education/Communication campaign must be strengthened by the local

government. The ―Adopt a River‖ program /project and the People’s Organizations in

Tanay must work hand in hand to help in the awareness in realizing the importance of

rehabilitation of Tanay River System.

LAGUNA LAKE DEVELOPMENT AUTHORITY Resource Management and Development Department


Water Quality

Assessment Report

Tanay River 2011

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