Water Quality Assessment - Laguna Lake …llda.gov.ph/dox/waterqualityrpt/rivers/StaCruz.pdfEngr. Jocelyn G. Sta Ana, OIC, Environmental Laboratory and Research Division For more information,

Water Quality Assessment

Of

Santa Cruz River

2011

Prepared and Written By:

Darlene T. Tingal – Biologist I

Gregory Alexis A. Ongjoco – Chemist II

Bileynnie P. Encarnacion – Biologist II

Reviewed By: Ms. Adelina C. Santos-Borja, OIC, Resource Mgt. and Development Department

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

For more information, please contact:

Environmental Laboratory and Research Division

Resource Management and Development Department

Laguna Lake Development Authority

Tel. No. 2866143

TABLE OF CONTENTS

Page

Introduction 1

Objectives 2

Methodology 2

Sampling Stations and Frequency of Sampling 3

Sample Collection, Preservation and Analysis 4

Field Observation and In-situ Measurements 4

Results and Discussion 4

Physico-Chemical Parameters 4

pH 4-5

Dissolved Oxygen 6

Biological Oxygen Demand 7

Nutrient Load 8

Nitrate 8

Inorganic Phosphate 8

Ammonia 9-10 Total Suspended Solids, Total Dissolved Solids and Total Solids 10-12

Turbidity 12-13

Other Parameters 13

Chloride 13

Conductivity 14

Oil and Grease 14

Alkalinity 15

Biological Parameters 15

Phytoplankton 16

Benthos 16-17

Microbiological Analyses 17-18

Conclusion 18-19

Recommendation 19-20

References 21

List of Tables

Page

Table 1 Stations Coordinates of Santa Cruz River 2

Table 2a.1 General Observation and Description of Sampling Station 1 to 5 (May) 23

Table 2a.2 General Observation and Description of Sampling Station 6 to 10 (May) 24

Table 2a.3 General Observation and Description of Sampling Station 11 to 1 5 (May) 25

Table 2b.1 General Observation and Description of Sampling Station 1 to 5 (Nov) 26



Table 3a Physico-Chemical Parameters of Santa Cruz River (May) 29

Table 3b Physico-Chemical Parameters of Santa Cruz River (Nov) 30

Table 3c Computed Unionized Ammonia per Station (May & Nov) 10

Table 4a Water Quality Assessment Based on Algal Population (May) 31

Table 4b Water Quality Assessment Based on Algal Population (Nov) 32

Table 5a Water Quality Assessment Based on Benthic Macroinvertebrates (May) 33

Table 5b Water Quality Assessment Based on Benthic Macroinvertebrates (Nov) 34

Table 6 Results of Microbiological Analysis (May & November) 35

List of Figures

Page

Figure 1 Map of Santa Cruz River and its Sampling Stations 3

Figure 2 pH 6

Figure 3 Dissolved Oxygen 7

Figure 4 BOD5 7

Figure 5 Nitrate 8

Figure 6 Inorganic Phosphate 9

Figure 7 Ammonia 10

Figure 8 Total Suspended Solids 11

Figure 9 Total Dissolved Solids 12

Figure 10 Total Solids 12

Figure 11 Turbidity 13

Figure 12 Chloride 13

Figure 13 Conductivity 14

Figure 14 Oil and Grease 15

Figure 15 Alkalinity 15

Figure 16 Pictures of Santa Cruz River Stations (May & November Sampling) 36-40

Water Quality Assessment of Santa Cruz River

Laguna Lake Development Authority – Environmental Laboratory and Research Division


Introduction

Santa Cruz is an urban class municipality and the capital town of the province of

Laguna. It is situated at the central portion of the Laguna province along the

southeastern coast of Laguna de Bay. It is also the seat of the provincial government

since 1885, giving the municipality an additional administrative function on the entire

province. It lies approximately 87 km southeast of Metro Manila via Calamba and

105 km via Pililla, in the province of Rizal and is geographically located at 14o 17’

latitude and 121o25’ longitude. It is accessible by land from the nearby 28

municipalities and by water through Laguna de Bay from Manila and some Rizal

towns. The municipality is bounded by Laguna de Bay on the north, by Lumban and

Pagsanjan towns in the east, Pagsanjan and Magdalena towns in the south, and Pila

and Liliw towns in the west.

Santa Cruz town is situated on the banks of the Santa Cruz River and course its way

along the eastern part of the famous Laguna de Bay. Santa Cruz is considered as the

service and commercial center on the eastern part of Laguna province. The town is

composed of 5 barangays in the Poblacion area and 21 classified urban barangays.

Santa Cruz River is one of the 21 major tributary rivers of Laguna de Bay

contributing about 15% of the total water in the lake. During the typhoon “Milenyo”,

the Calumpang Diversion Dam was destroyed due to overflowing of the river. Built in

1970, the dam channeled irrigation canals around the Calumpang area. The water is

used as a source of irrigation for 2185 hectares ricefields in Pila, Santa Cruz, Liliw,

Victoria and Nagcarlan. The riverbed is characterized by rocks, pebbles to sandy

bottom where quarrying along the river was also one source of income aside from

fishing. According to the National Irrigation Authority, quarrying could be the cause

of erosion and deepening of riverbed to 12 m lower than the old depth. The width and

length of the river could be comparable to Pagsanjan River. However, the volume and

capacity of Santa Cruz River were exceeded during the tropical cyclone “Santi”

(2009). Santa Cruz River submerged 85% of the town, 6 ft at Brgy. San Pablo Norte,

waist-deep at Brgy. Santisima Cruz and San Pablo Sur while leg-deep at Brgy. Inang

Awa.

According to Water Usage and Classification for Freshwater System used by DENR

Santa Cruz River was classified as Class D, which is suitable for agricultural

irrigation, livestock watering and industrial water supply (WQ Status Report, 2005).

However, in 2001-2005, one of the river tributaries that passed the Class C dissolved

oxygen criterion was Santa Cruz River (EMB 2006). The river runs through

municipalities and considered as fishing ground to small fish farmers along the area.

Fishes caught in the river are tilapia, dalag, shrimp, kanduli and other fishes including

invasive species like knifefish and janitor fish.



2

Objectives

In 1996 LLDA launched its River Rehabilitation Program utilizing an integrated

approach on the management of the watershed, taking into account the water quality

and other activities that thrives along the river system all the way to Laguna de Bay.

As part of the River Rehabilitation Program of Resource Management and

Development Department (RMDD), the assessment of the water quality of Santa Cruz

was undertaken for the dry and wet season for the purpose of determining seasonal

variations of the water quality in terms of biological, chemical and bacteriological

parameters. Water quality was assessed based on the biological organisms

characterized as clean to polluted indicators and the physico-chemical parameters.

Other observations in relation to development and activities within the river system

and its watershed were taken into account. The study serves as baseline information

on the use and activity of the Santa Cruz River and its watershed.

Methodology

Sampling Stations and Frequency of Sampling

Fifteen (15) sampling stations at various sections of the river and its tributaries were

already established since 1998. Reconnaissance of the established stations was again

done to determine if changes in the original stations need to be made. Sampling

stations were selected strategically along the Santa Cruz River and its tributaries and

coordinates of each station were established using the Global Positioning System

(GPS) presented in Table 1. Stations established along the stretch of the river and

representative section of its tributaries are shown in Fig. 1. The frequency of

sampling was represented by two seasons. The May (May 17 and 18, 2011) represent

the wet season while November (November 24 and 28, 2011) represent the dry

season.

Table 1. Stations Coordinates of Santa Cruz River

Station Location Coordinates

1 Mouth (Santa Cruz) P 0327797 1580793

2 Brgy. Santo Angel P 0328548 1579893

3 Brgy. Pagsawitan P 0329736 1577880

4 Brgy. Calumpang P 0328151 1568855

5 Brgy. Sta. Lucia P 0328152 1568680

6 Brgy. Bancoro P 0328464 1567064

7 Brgy. Palina P 0329238 1563630

8 Brgy. Balinacon P 0329270 1563038

9 Brgy. San Francisco P 0329720 1560074

10 Brgy. Pook P 0327773 1560676

11 Brgy. Laguan P 0326441 1561843

12 Brgy. Panglan P 0332779 1563381

13 Brgy. Ibabang San Roque P 0332430 1563198

14 Brgy. Palayan P 0327511 1563348

15 Brgy. Cabuyew P 0328852 1566677



3

Fig. 1. Map of Sampling Stations of Santa Cruz River



4

Sample Collection, Preservations and Analysis

Water samples were collected in each station by grab method and with the use of

plastic pail in stations with depth more than 1 foot. The water samples for chemical

analysis were placed in the designated container with label and preserved in the cooler

with ice. Microbiological samples were collected by grab method using the sterilized

bottles and preserved with ice in a separate cooler. Samplers used for the collection of

biological samples were surber sampler and ekman dredge. Benthic flora and fauna

were collected using surber sampler for water depth below 1 foot while ekman dredge

for water depth 1 foot and above. Sediment samples collected using ekman dredge

were processed by allowing the collected sediment to pass through a sieve with mesh

size of 180 m. The samples left in the sieve was transferred to a screw cap plastic

container of 100 and 250 ml capacity for flora and fauna analysis, respectively.

Samples for benthic flora were preserved with 3 to 5 drops of Lugol’s solution while

benthic fauna with 2 ml of formalin. Samples for biological samples were stored

under room temperature prior to analysis. All samples collected were brought to the

Environmental Laboratory and Research Division and submitted for analysis. Method

of analysis was based on the Standard Methods for the Examination of Water and

Wastewater (21st edition).

Field Observation and In-situ measurements

Field observations recorded during the wet and dry sampling are presented in Tables

2a and 2b. Water temperature ranged from 21 to 30oC in May and 22 to 27

oC in

November in all stations. Weather condition was sunny in May while in November,

sunny to partly cloudy, due to previous storm. The water condition was clear to

greenish in May and greenish to brownish in November. Water level was low in May

while in November a rise in the level of water was observed as boulders and big rocks

were already submerged in water. Some garbage was observed along the sides of the

tributaries far from residential area while the stretch of the river from Brgy.

Calumpang station to mouth, garbage was observed on sides of the river and floating

in the water surface. Patches of water hyacinth was observed floating from Stn. 3

(Brgy. Pagsawitan) going to Stn. 1 (mouth). In November, thick growth of water

hyacinth covering almost the entire river was observed in Station 1 (mouth). There

was an on-going construction of a new bridge in the said station and both sides of the

river were full of excavated soil leaving the river width smaller than the original size.

Results and Discussion

The Physico-chemical parameters and values obtained for both sampling are

presented in Table 3a and 3b. Results of analysis were assessed based on the water

criteria for Class C waters, that is, for fisheries and aquaculture as provided in the

DENR AO 34 and are presented below:

a) pH

The pH value of water helps us understand the kind of acidity or

alkalinity in the water. The standard criteria for pH value set for Class

C waters range from 6.5-8.5 expressed in units. The pH value of water

samples collected in May range from 5.8 to 7.4. Out of the15 stations,



5

12 stations passed the DENR criterion set for pH value while 3 stations

obtained a pH value of 5.8 (Station 9) and pH of 6.4 (Stns. 8 and 13),

which are below the criterion set for Class C waters. The water in

Station 9 came out from beneath the rocks and did not pass through the

main canal of the river. Residents said that a spring water outlet is

present underneath. The water was clear and cold (21oC) during the

time of sampling (May). The water in the area is used for washing and

bathing of residents and maintained clean all throughout. In November,

the pH value obtained ranged from 7 to 8.7. All stations except Stn. 6

conformed to the criteria set for Class C waters. An increase in the pH

value of 7 was observed in Station 9 (San Francisco). The main canal

was filled with water (flood/rainwater) aside from the spring water

underneath the rocks compared to the previous sampling. The change

in the pH value could have been attributed to the mixed water brought

by rainfall experienced the previous week and spring water underneath

the rocks that flows into the river. The highest pH value obtained was

8.7 in Stn. 6 (Brgy. Bancoro). The presence of dried leaves and

bamboo poles dumped/washed into the river could have contributed to

the slight increase in pH value.

Station 9 situated at San Francisco, River tunnel dried (May sampling)

Station 9 (San Francisco), River tunnel with overflowing water (November sampling).



6

Results showed that pH value increases in November compared to May

sampling. This could have been due to the flood/rainwater that flows

into the river carrying with it particles and other solid waste.

pH

4.0

5.0

6.0

7.0

8.0

9.0

10.0

Stat

ion 1

Stat

ion 2

Stat

ion 3

Stat

ion 4

Stat

ion 5

Stat

ion 6

Stat

ion 7

Stat

ion 8

Stat

ion 9

Stat

ion 1

0

Stat

ion 1

1

Stat

ion 1

2

Stat

ion 1

3

Stat

ion 1

4

Stat

ion 1

5

May Sampling

NovemberSampling

Class C WQCriteria

Figure 2. pH of Santa Cruz River (May and November Sampling)

b) Dissolved Oxygen

Dissolved oxygen (D.O.) is one indicator of a good water quality of a

stream or any water body. The amount of dissolved oxygen in an

ecosystem is affected by temperature, organic matter coupled by

bacterial activity and photosynthesis. Photosynthesis helps replenish

dissolved oxygen. This process could be experienced in areas where

there is greater sunlight. The minimum dissolved oxygen value ideal

for living organisms to survive is 5mg/L; below this amount some

species could not survive. However, other organisms can tolerate even

lower than the minimum value. The whole stretch of Santa Cruz River

including its tributaries passed the criteria for Class C waters. The

continuous water movement from the upstream going towards the

mouth with a fast to moderate flow enhances aeration process in the

river system.

In May, the D.O. concentrations in all stations ranged from 5 to 8.3

mg/L and conformed with the criterion for Class C waters. The value

of 5 mg/L was obtained in Station 5. The water in this area was

confined/retained in a “dam-like” structure with very little water

movement; part of it is diverted to irrigational canal while the rest

overflow into the mainstream of Santa Cruz River.

Dissolved oxygen values obtained in November sampling ranged from

5.2 to 10.9 mg/L in all stations and conformed to the DENR criteria.

The highest value (10.9 mg/L) obtained was in station 11. In this area,

two spring outlets along the side of the riverbank was observed free

flowing into the river and water at that time was fast flowing. The

contribution of spring water and the turbulence of the flow enhanced

aeration process and could be the reason for a high value in dissolved

oxygen. The value of 5.2 mg/L was obtained in the mouth area. At the

time of sampling, the area was fully covered with water hyacinth and



7

excavated soil from the on-going construction of a new bridge was

dumped on both sides of the river. With this condition, penetration of

light could have hindered photosynthesis activity thus resulted to low

dissolved oxygen value.

Dissolved Oxygen, mg/L

0

2

4

6

8

10

12

Stat

ion 1

Stat

ion 2

Stat

ion 3

Stat

ion 4

Stat

ion 5

Stat

ion 6

Stat

ion 7

Stat

ion 8

Stat

ion 9

Stat

ion 1

0

Stat

ion 1

1

Stat

ion 1

2

Stat

ion 1

3

Stat

ion 1

4

Stat

ion 1

5

May sampling

Novembersampling

Class C WQMin Criteria

Figure 3. Dissolved Oxygen of Santa Cruz River (May and November Sampling)

c) Biochemical Oxygen Demand (BOD5)

Biochemical Oxygen Demand (BOD5) is the amount of oxygen

consumed by microorganisms to decompose organic waste in the

water. The criterion for Class C water, such as river is 7 average and

10 mg/L maximum. BOD5 value in May ranged from 1 – 6 mg/L while

in November value of 1 to 3 mg/L was obtained. The station that

obtained the value of 6 mg/L was Station 2. The area is occupied by

residential and commercial establishments (wet and dry market). The

slight increase in the amount of BOD5 could be due to an increase of

decomposing waste and other organic matter washed and brought into

the river. All the stations both in May and November sampling passed

the criterion for Class C water of 7 (10) mg/L.

Figure 4. Biological Oxygen Demand of Santa Cruz River (May and November Sampling)



8

d) Nutrient Load

Human activity plays a vital role in the increase of nutrients in the

water especially nitrogen and phosphorus. Excess input of nutrients

could cause a change in the quality of water. Excess amount of these

nutrients enhance growth of algae. Presence of garbage dumped along

the sides of the river, agricultural run-off and households sewage

directly discharged into the river could contribute to the increase of

nutrients and can contribute to high biological oxygen demand (BOD).

The DENR criteria set for nitrate and inorganic phosphate are 10 mg/L

and 0.4 mg/L, respectively. In May, nutrient load such as Nitrate (NO3)

and Inorganic Phosphate (IPO4) ranged from 0.0929 to 1.47 mg/L and

0.2263 to 0.6331 mg/L, respectively. All stations passed the 10mg/L

criterion set for nitrate. The highest amount of nitrate was observed in

Station 11 (1.47 mg/L) while the lowest was in Station 5 (0.0929

mg/L). Out of the fifteen (15) stations, seven (7) stations passed the 0.4

mg/L inorganic phosphate criterion set for rivers while eight (8)

stations were beyond the criterion. The highest amount of IPO4

obtained was in station 5 (Sta Lucia) with value of 0.6331 mg/L while

station 12 (Panglan) obtained the lowest value of 0.0904 mg/L.

Stations (Stns 1, 4, 5, 9, 10, 11, 13 and 15) that obtained a value

exceeding the criterion were all situated in a residential and farm area.

Domestic waste discharged directly into the river and fertilizer runoff

could have contributed to the slight increase in IPO4.

In November, a slight change in the amount of NO3 and IPO4 was

obtained with values ranging from 0.1498 to 1.5348 mg/L and 0.001 to

0.6258 mg/L, respectively. The amount of nitrate in station 11 obtained

the highest value (1.5348 mg/L) while the lowest (0.1498 mg/L) was

observed in station 15. Highest value of Inorganic phosphate was

0.6258 mg/L in Stn. 14 while 0.001 mg/L in Stn. 12 was the lowest

value. The slight change in the amount of NO3 and IPO4 could be due

to an increase in suspended particles (nutrients and planktons) carried

out by flush flood during previous rainfall.

Nitrate, mg/L

0.0000

0.2000

0.4000

0.6000

0.8000

1.0000

1.2000

1.4000

1.6000

1.8000

Statio

n 1

Statio

n 2

Statio

n 3

Statio

n 4

Statio

n 5

Statio

n 6

Statio

n 7

Statio

n 8

Statio

n 9

Statio

n 10

Statio

n 11

Statio

n 12

Statio

n 13

Statio

n 14

Statio

n 15

Maysampling

Novembersampling

Figure 5. Nitrate of Santa Cruz River (May and November Sampling)



9

Figure 6. Inorganic Phosphate of Santa Cruz River (May and November Sampling)

Ammonia is a strong colorless gas and exists in two forms in the water,

unionized ammonia (NH3) and ionized ammonia (NH4). The 1999

Update of Ambient WQ Criteria for Ammonia cited that unionized

ammonia is the principal form of toxic ammonia and reported toxic to

freshwater organisms at concentrations ranging from 0.53 to 22.8

mg/L.

Based on the results obtained, Ammonia (NH3) ranged from 0.0149 to

0.9884 mg/L in May. Eleven (11) stations showed results of below 0.2

mg/L, a concentration that is not critical to freshwater organisms.

Plants are more tolerant of ammonia than animals while invertebrates

are more tolerant than fishes (EPA Technical Fact Sheet on Ammonia).

Unionized ammonia affects the hatching and growth development of

fishes depending on the species tolerable limits. Some fishes like trout

fry can tolerate up to 0.2 mg/L while striped bass can tolerate up to 1.2

mg/L. The effect may be loss of equilibrium, increase respiratory

activity and oxygen uptake (EPA Technical Fact Sheet on Ammonia).

Four (4) stations were beyond 0.2 mg/L. The highest value in May was

obtained in Station 5 (Sta. Lucia) at 0.9884 mg/L while the lowest

value of 0.0149 mg/L was observed in Station 12 (Panglan). Station 5

is situated in a residential area and with a “dam-like” structure

controlling the water, diverting part of it to an irrigational canal. The

flow of water was very slow to still. Since water is being confined for a

period of time, a slight increase in the amount of ammonia could have

occurred due to change in pH and temperature. Some study found that

toxic levels of ammonia are both pH and temperature dependent (1999

Update of Ambient WQ Criteria for Ammonia). In November, the

amount of ammonia ranged from 0.0587 to 0.181 mg/L and was

observed in Stations 6 and 13, respectively. All stations showed value

of ammonia below 0.2 mg/L.



10

Station Location

Unionized

Ammonia, mg/L

(November)

Unionized

Ammonia, mg/L

(May)

Station 1 Mouth (Sta. Cruz) 0.00483 0.00077

Station 2 Brgy Sto Angel 0.00180 0.00026

Station 3 Brgy Pagsawitan 0.01273 0.00034

Station 4 Brgy Calumpang Liliw 0.00410 0.00052

Station 5 Sta. Lucia 0.07580 0.00026

Station 6 Brgy Bancoro 0.00897 0.00082

Station 7 Brgy Palina 0.00128 0.00018

Station 8 Brgy Balinacon 0.00132 0.00015

Station 9 San Francisco 0.00074 0.00003

Station 10 Brgy Pook 0.00772 0.00015

Station 11 Brgy Laguan 0.00075 0.00020

Station 12 Brgy Panglan 0.00201 0.00013

Station 13 Brgy San Roque 0.01120 0.00024

Station 14 Brgy Palayan 0.00318 0.00046

Station 15 Brgy Cabuyao 0.00469 0.00023

Station Location

Unionized

Ammonia, mg/L

(November)

Unionized

Ammonia, mg/L

(May)
















Station Location

Unionized

Ammonia, mg/L

(November)

Unionized

Ammonia, mg/L

(May)
















Figure 7. Ammonia of Santa Cruz River (May and November Sampling)

Given the value of temperature and pH of the water, the concentration

of unionized ammonia was computed and presented in Table 3c.

Unionized ammonia concentrations of all the stations from both May

and November sampling are all below the 1999 Update of Ambient WQ

Criteria for Ammonia of 0.53 to 22.8 mg/L.

Table 3c. Computed unionized ammonia per station (May and November).

e) Total Suspended Solids, Total Dissolved Solids and Total Solids

Suspended solids are solid particles, which may be organic and

inorganic, usually suspended in the water. These include silts, plankton

and industrial and/or domestic waste. The presence of suspended



11

solids/particles in the water could affect the light penetration

permanently or seasonal and also have an impact in the water quality.

Total suspended solids ranged from <1 to 11 mg/L in May and <1 to

26 mg/L in November. The lowest value (<1 mg/L) was observed in

two stations (Stns. 12 and 13) while the highest value (11 mg/L) was

obtained in two stations (Stns.5 and 7) during May sampling. In

November, two stations (Stns.9 and 12) obtained a value of <1 mg/L

while the value of 26 mg/L was observed in Station 14.

Total Suspended Solids, mg/L

0

5

10

15

20

25

30

Statio

n 1

Statio

n 2

Statio

n 3

Statio

n 4

Statio

n 5

Statio

n 6

Statio

n 7

Statio

n 8

Statio

n 9

Statio

n 10

Statio

n 11

Statio

n 12

Statio

n 13

Statio

n 14

Statio

n 15

May sampling

Novembersampling

Figure 8. Total Suspended Solids of Santa Cruz River (May and November Sampling)

Total Dissolved Solids are the total amount of mobile charged ions,

including minerals, salts or metals dissolved in the water, expressed in

units of mg/L. Like suspended particles they also affect the quality of

the water, density differences produced by stratification that may be

permanent, transient or seasonal.

The amount of total dissolved solids in wet season ranged from 132 to

254 mg/L. The highest value was obtained in Station 14 (Palayan)

while the lowest value in Station 12 (Panglan). The increase in the

amount of dissolved solids could be due to soil/agricultural runoff from

rice farming present in the area (Station 14). During the dry season, the

amount of dissolved solids ranged from 79 to 241 mg/L. The highest

value was obtained in Stations 5 and 10 (Sta Lucia and Pook) while the

lowest was still obtained in Station 12 (Panglan). Stations 5 and 10 are

both situated in a thickly populated area and with a dam structure

where the water was being confined for irrigation and fishpond

purposes.



12

Total Dissolved Solids, mg/L

0

50

100

150

200

250

300

Statio

n 1

Statio

n 2

Statio

n 3

Statio

n 4

Statio

n 5

Statio

n 6

Statio

n 7

Statio

n 8

Statio

n 9

Statio

n 10

Statio

n 11

Statio

n 12

Statio

n 13

Statio

n 14

Statio

n 15

May Sampling

NovemberSampling

Figure 9. Total Dissolved Solids of Santa Cruz River (May and November Sampling)

Total Solids is a measure of all the suspended colloidal and dissolved

particles in the water. This includes dissolved salts, silts and plankton.

Soil erosion and agricultural runoff (fertilizer, suspended particles,

etc.) are both contributors of solids in the water. The amount of Total

Solids ranged from 132 to 263 mg/L in May while in November the

amount ranged from 79 to 256 mg/L. The highest values of 263 and

256 mg/L were obtained in Station 14 (Palayan) in May and Station 5

(Sta Lucia) in November sampling, respectively. Station 12 (Panglan)

obtained the lowest values of 132 and 79 mg/L during May and

November, respectively.

Station 12 is situated in descending slopes and water flows freely

flushing solid particles downstream while Station 14 is situated in an

agricultural area where soil erosion from rice paddies could have

contributed to the amount of particles in the water.

Figure 10. Total Solids of Santa Cruz River (May and November Sampling)

f) Turbidity

Turbidity is a measure of the degree in which the water loses its

transparency due to the presence of suspended particulates. It also

Total Solids, mg/L

0

50

100

150

200

250

300

Statio

n 1

Statio

n 2

Statio

n 3

Statio

n 4

Statio

n 5

Statio

n 6

Statio

n 7

Statio

n 8

Statio

n 9

Statio

n 10

Statio

n 11

Statio

n 12

Statio

n 13

Statio

n 14

Statio

n 15

May sampling

Novembersampling



13

expresses the clarity of the water. Turbidity increases as a result of

suspended solids in the water such as clay, silt or even microorganisms

like plankton, which interferes with the transmission of light, reduces

photosynthetic activity, and hence contributes in the decline in the

productivity of a water body. Turbidity value expressed in NTU ranged

from <1 to 13 in May and <1 to 16 in November. Both low values

obtained during the wet and dry season were observed in Station 9

(San Francisco) while both high values (wet and dry) were obtained in

Station 3 (Pagsawitan). The presence of clear spring water in Station 9

contributes to the clarity of water.

Turbidity, NTU

0

2

4

6

8

10

12

14

16

18

Statio

n 1

Statio

n 2

Statio

n 3

Statio

n 4

Statio

n 5

Statio

n 6

Statio

n 7

Statio

n 8

Statio

n 9

Statio

n 10

Statio

n 11

Statio

n 12

Statio

n 13

Statio

n 14

Statio

n 15

May sampling

Novembersampling

Figure 11. Turbidity of Santa Cruz River (May and November Sampling)

g) Other Chemical Parameters

Chloride is a useful and reliable chemical indicator of

river/groundwater fecal contamination as chloride is a non-reactive

solute and ubiquitous to sewage and potable water. The criterion value

for chloride is 350 mg/L for Class C waters. Chloride value ranged

from 11 to 37 mg/L in May and 7 to 15 mg/L in November. All values

are below the criterion for Class C waters.

Chloride, mg/L

0

50

100

150

200

250

300

350

400

Statio

n 1

Statio

n 2

Statio

n 3

Statio

n 4

Statio

n 5

Statio

n 6

Statio

n 7

Statio

n 8

Statio

n 9

Statio

n 10

Statio

n 11

Statio

n 12

Statio

n 13

Statio

n 14

Statio

n 15

Maysampling

Novembersampling

Class C WQMax Criteria

Figure 12. Chloride of Santa Cruz River (May and November Sampling)



14

Conductivity indicates the presence of ions capable to conduct

electricity. High conductivity is an indicator of total dissolved solids

and salinity. It is an indirect measure of water salinity and one of the

most common and convenient methods used to test water. It is

significantly affected by temperature and strongly dependent upon the

ionic composition of water. Conductivity values obtained at Santa Cruz

river range from 114 to 372 S/cm in May while 49 to 238 S/cm in

November. The highest value was obtained in Station14 (Palayan) and

Station 11 (Laguan), 372 and 238 S/cm, for May and November

sampling, respectively. The lowest value of 114 and 49 S/cm for both

sampling (May and November) was observed in Station 12 (Panglan).

Conductivity, µS/cm

0

50

100

150

200

250

300

350

400

Statio

n 1

Statio

n 2

Statio

n 3

Statio

n 4

Statio

n 5

Statio

n 6

Statio

n 7

Statio

n 8

Statio

n 9

Statio

n 10

Statio

n 11

Statio

n 12

Statio

n 13

Statio

n 14

Statio

n 15

MaysamplingNovembersampling

Figure 13. Conductivity of Santa Cruz River (May and November Sampling)

Dissolved and emulsified oil and grease is extracted from water by

intimate contact with an extracting solvent. The criteria set for oil and

grease for Class C water is 2 mg/L. Oil and grease values during May

sampling showed a slight increase in six (6) stations ranging from 3 to

4 mg/L. The following stations with a slight increase in oil and grease

were Stations 1, 6, 7, 8, 14 and 15. The slight increase in value could

be due to run-off and other domestic waste dumped along the sides and

or carried into the water. The amount of oil and grease during

November ranged from <1 to 2 mg/L. All stations passed the criterion

for Class C waters.



15

Oil and Grease, mg/L

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

Statio

n 1

Statio

n 2

Statio

n 3

Statio

n 4

Statio

n 5

Statio

n 6

Statio

n 7

Statio

n 8

Statio

n 9

Statio

n 10

Statio

n 11

Statio

n 12

Statio

n 13

Statio

n 14

Statio

n 15

May sampling

Novembersampling

Class C WQMax Criteria

Figure 14. Oil and Grease of Santa Cruz River (May and November Sampling)

Alkalinity is a measure of the amount of carbonates and bicarbonates

in water. Alkalinity is considered as the key to water balance. The

values of alkalinity during May sampling ranged from 48 to 156

mgCaCO3/L while November sampling ranged from 40 to 136

mgCaCO3/L. The highest values of 156 and 136 mgCaCO3/L was

obtained in Station 5 in May and Station 6 in November while the

lowest value of 48 and 40 mgCaCO3/L were both obtained in Station

12 (Panglan) in May and November sampling, respectively.

Alkalinity, mg CaCO3/L

0

20

40

60

80

100

120

140

160

180

Statio

n 1

Statio

n 2

Statio

n 3

Statio

n 4

Statio

n 5

Statio

n 6

Statio

n 7

Statio

n 8

Statio

n 9

Statio

n 10

Statio

n 11

Statio

n 12

Statio

n 13

Statio

n 14

Statio

n 15

Maysampling

Novembersampling

Figure 15. Alkalinity of Santa Cruz River (May and November Sampling)

2. Biological Analyses

Biological parameters are widely used in assessing the quality of water

of a stream/river and lakes. They are a good indicator of water quality

because they are directly affected by the sudden change in the

ecosystem. Their composition and abundance depend on the

environmental condition they thrive in. Biological parameters such as,

aquatic flora and fauna are useful indicators of good water quality.

Below are the results of the biological analyses obtained in the samples

collected in May and November.



16

a) Phytoplankton

Algae are unicellular organisms or microscopic plants that play as the

primary consumer in the food web of an ecosystem. Aquatic organisms

such as zooplankton, small animals, fishes and other aquatic animals

depend on aquatic plants to survive. The qualitative and quantitative

analysis of algae are useful tool in assessing water quality of rivers,

since these organisms can be found attached to stones or plants or

settled at the bottom. A sudden change in the quality of the water will

directly affect growth and composition of algae. The water quality was

assessed according to the percentage value of the indicator species

identified (Table 4a and 4b). Species of algae are classified as to clean

water or polluted water indicator. As shown in Table 4a, the stations in

May sampling were classified as moderately polluted to polluted

waters while in November one station was classified as relatively clean

water and the rest of the stations classified as moderately polluted to

polluted.

Based on the qualitative and quantitative analysis of algae, results

showed that 21 genera of algae were identified in May while 17 genera

in November. The most diverse group of algae was mostly diatoms

(pennate type) found almost in all stations. Of the 15 established

stations, four (4) stations were classified as moderately polluted and

eleven (11) stations as polluted in May while in November, one (1)

station was classified as relatively clean, four (4) stations as

moderately polluted and ten (10) stations as polluted. In May, stations

classified as moderately polluted were Stations 12, 9, 3 and 1. Station

11 showed a 100% polluted, based on the percentage organisms

identified. In November, Station 9 was classified as relatively clean

with a percentage value of 72.7% of the total counts. Clean water

organisms comprised of 3 genera namely; Cocconeis sp., Navicula sp.

and Pinnularia sp. Of the clean water algae, Navicula sp. was the most

common species identified. Clean water algae were also found present

in moderately polluted station, however, percentage occurrence were

minimal compared to polluted water organisms. Polluted water

organisms comprised of 4 genera namely; Oscillatoria sp., Nitzschia

sp., Gomphonema sp. and Spirogyra sp. Other species of algae were

also identified and occur in numbers. Pennate group of diatoms

dominate the other species identified. Achnanthes sp., Amphora sp.,

Cymbella sp., Diploneis sp., Synedra sp., Stauroneis sp.,

Stephanodiscus sp. etc. were among the species of algae identified that

falls under other species.

b) Benthos

Organisms thriving in the riverbed or attached to sediments, rocks and

plants are commonly known as benthic fauna. This group has a wide

range of species that are considered as residents of an ecosystem.

Benthos population and its percentage contribution for both May and

November sampling were presented in Table 5a and 5b.



17

In May, water quality assessment based on benthos analysis showed

that 5 stations of the tributaries and Santa Cruz mainstream stations 1,

2 and 3 were classified as moderately polluted. Two stations of the

tributaries (Stns. 9 and 10) were classified as polluted while 4 stations

(Stns. 7, 8, 12 and 14) in the tributaries and 1 station (Stn. 4) in the

mainstream were assessed as clean. Based on the qualitative and

quantitative analysis of benthos, about 45 individuals were identified

during May sampling. The most diverse group is Class Insecta. Others

such as gastropods, crustaceans and fishes were also found present.

Laguan (Stn.11) and Pagsawitan (Stn. 3) were the two stations both

found most diverse in number of individuals identified. Thiara sp., a

gastropod, dominated the counts in Stations 2 (Sto. Angel) and 6

(Bancoro) with values of 2521 and 1211 individuals, respectively.

Thiara sp. is an indicator of moderately polluted water and it is capable

of carrying some gas exchange in most part of the bodies aside from

the gills. Aside from the characteristic of the organisms, the condition

of the water and its sediment could favor the proliferation of this

organism tolerant to slight pollution.

During the November sampling, benthic analysis showed that eight (8)

stations were classified as clean, six (6) stations as moderately polluted

and one (1) station as polluted. The water condition on the eight (8)

stations was fast flowing and the river width is much wider than the

rest of the stations carrying solid materials/waste easily towards

downstream. The presence of big rocks and boulders on the riverbed

could also help in the turbulence and aeration of the water. The most

dominant species identified was a gastropod, Thiara sp. with values

ranging from 508 to 904 individuals. Other species present were

Corbicula sp. and Viviparus sp., both of which were observed along

the downstream area (Stations 1 and 2). One (1) station (Stn. 6) was

classified as polluted. The polluted organisms identified were mostly

chironomid larvae and pupae but minimal in counts. Other dipterans

and Physa sp. were also found present.

3. Microbiological Analyses

The Microbiological characteristic or microbiological component of a

water body expressed in Most Probable Number (MPN) could be used

as an index of the presence of coliform group. This group is a useful

indicator of the degree of pollution and whether water is fit or unfit for

recreation and other beneficial use. E. coli is a kind of bacteria most

common in human and animal waste. For Class C waters, the criterion

for total coliform is 5000 MPN/100 ml.

Result shows that E. coli detection appeared to be present in most of

the stations during the May sampling (Table 6). There were four (4)

stations (Stations 6, 7, 8 and 9) that conformed to the criteria for total

coliform, ranging from <20 to 5000 MPN/100 ml. Station 9 obtained a

value of less than 20 MPN/100 ml in May sampling and showed no



18

detection of E. coli. The upper portion of the river was dried and water

was only observed present at the lower portion (Stations picture 9c &

9d). The water condition at the time of sampling was fast flowing and

very cold that comes out underneath the stones and flows freely into

the lower portion of the river. Residents said that spring water outlet is

present in the area. Since water comes from spring outlet and observed

clear, residents use it for washing, bathing and other domestic

purposes. In May, eleven stations (Stations 1, 2, 3, 4, 5, 10, 11, 12, 13,

14 and 15) did not conform to the criteria of 5000 MPN/100 ml. The

total coliform values obtained in the eleven stations ranged from 8,000

to 160,000 MPN/100 ml. The highest value of detection was observed

in Stations 3 and 13, respectively. The area in Station 3 was thickly

populated (residential) while the presence of birds nesting under the

bridge including its excretes seen along the bridge and on stones in the

river was observed in Station 13. The effect of animal waste/excretes

could have increased the bacterial content in the water.

In November, high values of total coliform ranged from 330 to

240,000 MPN/100 ml. Station 13 obtained the highest value of

240,000 MPN/100 ml while the lowest value was detected in Station 9.

The station that obtained high coliforms counts was within thickly

populated area (residential). In Station 9, the presence of water in the

main canal was observed, which then overflowed into the lower

portion of the river mixing with the water coming from the spring

outlet. The excessive water could be due to the previous rains

experienced during the weekend, where it drained and flowed into the

river. Microbiological result showed a value of 330 MPN/100 ml of

coliform counts in Station 9. However, the minimal amount was within

the criteria for Class C waters. The runoff water that mixed with the

water in the lower portion could have introduced microorganisms in

the water.

Fecal coliform values ranged from <20 to 160,000 MPN/100ml and

170 to 240,000 MPN/100ml in May and November, respectively.

Station 9 was detected with lowest value of <20 MPN/100ml and 170

MPN/100ml, in May and November, respectively.

Based on the values obtained for microbiological analysis and the E.

coli detection, the water in all stations are not fit for domestic use

except in station 9 which is within the criterion for Class C waters.

Conclusion

Santa Cruz River was assessed based on the biological, bacteriological and physico-

chemical parameters collected during May and November sampling. The dissolved

oxygen of the water meets the criterion of Class C waters in May and November

sampling. The moderate to fast flow on the whole stretch of the river including its

tributaries helps in aerating the water thus, increasing its oxygen content. The pH

value meets the criterion for Class C waters except in Station 9, which obtained a



19

slight increase due to the mixed rain and spring water. All stations conformed with the

BOD5 criterion set at 7 to 10 mg/L for Class C waters. Although BOD5 showed

slightly higher values in May (1 to 6 mg/L) compared to November (1 to 3 mg/L).

Other chemical parameters showed a slight increase during November due to a

previous rainstorm. The unionized ammonia computed based on the pH and

temperature values showed that all stations were below 0.2 mg/L, which is not critical

to freshwater organisms. The total suspended solids (TSS), total dissolved solids

(TDS) and total solids (TS) obtained a slight increase in November compared to May

sampling. Oil and grease ranged from 3 to 4 mg/L in May while <1 to 2 in November.

Water quality assessment of Santa Cruz River based on algal population showed that

four (4) stations were classified as moderately polluted and eleven stations (11) as

polluted during the May sampling. In November sampling, one (1) station was

classified as clean, four (4) stations as moderately polluted and ten (10) stations as

polluted.

Based on benthic fauna, in May sampling five (5) stations were classified as clean,

eight (8) as moderately polluted and two (2) as polluted while in November sampling

eight (8) stations were classified as clean, six (6) stations as moderately polluted and

one (1) station classified as polluted.

Microbiological results showed that total coliform ranged from <20 to 160,000

MPN/100 ml in May while 330 to 240,000 MPN/100 ml in November. E. coli

bacteria were detected in all stations. Fecal coliform ranged from <20 to 160,000

MPN/ml in May while in November an increase in number ranging from 170 to

240,000 MPN/100 ml was observed.

The stretch of Santa Cruz River and its tributaries do not have any treatment facility

that will help in controlling polluted water into Laguna de Bay. Santa Cruz River may

have also relied on self-purification process, a process of sedimentation of suspended

solids and oxidation of soluble materials before discharging into Laguna de Bay. The

water condition of Santa Cruz river and its tributaries up to station 4 (Calumpang)

were all fast flowing, a condition which has turbulence of aerating the water and at the

same time oxidation of soluble particles/waste before going downstream and into the

lake. However, in station 3 up to the mouth area, sedimentation of suspended solids

could occur due to very slow flow and still condition of water.

The “adopt-a-river” program of LLDA began last 2011 and continuously

implemented throughout. The main stretch of Santa Cruz River was adopted by the 5

Local Government Units last 5 March 2012 (MOA signing) while its minor tributaries

were adopted by group of organizations and establishments within the vicinity of the

river banks. The project had implemented programs such as tree planting along the

riverbanks and river clean-up activities.

Recommendation

In rehabilitating a river system, physical survey of the whole stretch of the river is

required to help in the identification of point sources. Its land uses and the bio-

physical structure of its sub-basins are also needed in the planning preparation to help



20

identify other contributing factors of pollution. Participatory planning by government

agencies, LGU’s, NGO and civic organization is very important.

Information/Educational/Communication campaign on the condition or state of the

river will help protect and rehabilitate the river. The “adopt-a-river” campaign/project

by any organization must be properly programmed and implemented. The River

Councils (RC-1999 Board Resolution #114) in every river system must be revived or

strengthened.



21

References

Madamba, L.S., Galapate, R.P., Decena A.M. and Casunuran, V.B.

1992. Pollution Load Contribution of Santa Cruz River to Laguna de

Bay. Phil. Journal of Science. Vol .121 (2).

Cooper, A.E., Cooper, E.A. and Howard J.A. 1919. On The Self-

Purification of Rivers and Streams. Biochem. Journal Vol. 13 (4).

Standard Method for the Examination of Water and Wastewater. 21st

Edition.

www.water-research.net/watershed/ammonia.htm. EPA Technical Fact

Sheet on Ammonia. 1999 Update of Ambient Water Quality Criteria

for Ammonia.

WEPA 1996. LLDA River Rehabilitation Program.

Wikipedia (free encyclopedia) Santa Cruz, Laguna Reference

Comprehensive Land Use Plan Santa Cruz Laguna Planning Period

2000 – 2010 Prepared by the Municipal Planning and Development

Staff (2000).



22

Tables and Figures



23

Station Number 1 2 3 4 5

Date 18 May 2011 18 May 2011 18 May 2011 17 May 2011 17 May 2011

Time 12:41 NN 12:15:00 NN 11:45 AM 12:20:00 NN 12:35 NN

Water Condition slow flow very slow flow moderately flowing fast flowing very slow flow to still

Air Temperature (oC) 31 30 29 32 31

Water Temperature (oC) 30 27 27 27 24

Color green green greenish greenish greenish

Nature of River Bed sandy/muddy sandy/muddy sandy sandy sandy/muddy

Weather Condition sunny sunny sunny sunny sunny

P 0328151

1568855

P 0328152

1568680

GPS Reading P 0327797

1580793

P 0328548

1579893

P 0329736

1577880

presence of water

hyacinth on both sides,

duck raising along the

shores, sand quarrying,

fishing area, residential

area (waste discharged

directly into the river), river

width approx. 20 m and

water depth ~ 2 m.

patches of water hyacinth,

concrete river banks,

residential and

commercial area (waste

discharged directly into

the river), presence of

garbage, river width

approx. 20 m and water

depth ~ 2 m.

2a.1. General Observation and Description of Sampling Stations

Stations Mouth of Sta Cruz riverSto Angel (Sta Cruz,

Laguna)

Pagsawitan

(Sta Cruz, Laguna)

Calumpang

(Liliw/Nagcarlan,

Laguna)

Sta Lucia

(Nagcarlan, Laguna)

Santa Cruz River (May Sampling)

Other Observations river water controlled by a

"dam-like structure"

(reservoir) diverted to

irrigational canal,

residential area (waste


the river), river banks

planted with

trees/bamboos & dried

leaves/twigs carried out

into the river, bathing and

washing, garbage on both

sides, small fishes seen in

the reservoir, river width


depth ~ <1 ft (deeper in

the reservoir).

washing and bathing area,

garbage, dried

leaves/branches and dead

animals floating on the

water surface, fishing area

(big knifefish caught

during sampling using

hook and line), river width


depth <2 m.

washing/bathing area,

dried leaves/twigs on both

sides, fist to head size

stones with few boulders,

river width approx. 30-40

m and water depth ~ <2

m.

Table



24



Time 12:05 NN

Water Condition fast flowing fast flowing fast flowing fast flowing fast flowing



Color greenish greenish greenish clear greenish

Nature of River Bed sandy sandy sandy sandy sandy



1567064

Brgy. San Francisco

(Nagcarlan, Laguna)

Brgy. Pook (Rizal,

Laguna)

P 0329238

1563630

P 0329270

1563038



the river), part of the water

diverted into the fishpond

with Tilapia sp., both sides

concrete as irrigational

canal, fist to head size

stones, river width approx.

2 m and water depth ~ <1

m.

StationsBrgy. Bancoro

(Nagcarlan, Laguna)

P 0329720

1560074

P 0327773

1560676

Brgy. Palina (Liliw,

Laguna)

residential area,

bathing/washing/fishing

area, river width approx. 8

m and water depth ~ <2

m.

Other Observations


Brgy. Balinacon

(Nagcarlan, Laguna)

area with boulders, stones

fist to head size,

vegetation on both sides,

grasses and trees near

the banks, low river

banks, river width approx.

10 m and water depth ~

<1 m.

Table 2a.2. General Observation and Description of Sampling Stations

residential area, water

don’t passed thru the

main river channel comes

out beneath the stones

(river pass the channel

during heavy rains), used

as laundry area, trees

/bamboos on both sides

of the banks, plenty of

dried leaves/branches

after the washing area,

river width approx. 1-2 m

and water depth ~ <1 m.

residential area, presence

of boulders, fist to head

size stones, water

controlled by a dam-like

structure used for diving

and swimming,

bathing/washing area,

river width approx. 8 m




25



Time 10:10 AM 9:48 AM 10:10 AM 8:40 AM 9:03 AM

Water Condition fast flowing fast flowing moderately flowing moderately flowing fast flowing



Color greenish clear brownish clear greenish brown



Brgy. Palayan

(Nagcarlan, Laguna)

Brgy. Cabuyew (Liliw,

Laguna)

Table 2a.3. General Observation and Description of Sampling Stations

StationsBrgy. Laguan

(Nagcarlan, Laguna)

Brgy. Panglan

(Majayjay, Laguna)


1561843

P 0332779

1563381

P 0332430

1563198

Brgy. Ibabang San

Roque (Liliw, Laguna)

P 0327511

1563348

P 0328852

1566677


Other Observations high river banks, pasture

area (goats/rooster farm),

few residential, fist to

head size stones, dried

leaves/branches on the

water surface and sides,


and water depth ~ 1 m.

water controlled by big

boulders forming different

sizes of pools used as

swimming/diving area,

picnic area, washing area,

presence of garbage

(snack wrappers etc. from

outings), trees/bamboos

on both sides, river width

approx. 10-12 m and

water depth ~ <2 m

(deeper inside the pools).



the river), fist to head siz

stone with few boulders,

too many birds (locally

called as "layang-layang")

flying under the bridge

causing lots of excrete

seen on stones and sides

of the river, river width

approx. 1-2 m and water

depth ~ <1 ft.

residential area, fist to

head size stones, few

boulders, trees/bamboos

on both sides, dried

leaves/branches present,

water on one sides with

water strider insect

(Gerris sp .), river width


depth ~ 1 ft.

few residential, vegetation

on one side (kangkong,

grasses), fist to head size

stones with medium size

boulders, presence of fish

fry seen near the shore,

presence of water strider

(Gerris sp .) on surface,





26


Date 28 Nov. 2011 28 Nov. 2011 28 Nov. 2011 28 Nov. 2011 28 Nov. 2011

Time 11:05 AM 11:30 AM 11:51 AM 12:15 NN 12:38 NN

Water Condition standing very slow flow slow flow fast flowing moderately flowing



Color greenish greenish greenish brown greenish grayish green

Nature of River Bed sandy/muddy sandy/muddy sandy sandy sandy/muddy


P 0328151

1568855

P 0328152

1568680

high water level boulders

no longer seen, grassy

area, water diverted into

irrigational canal,

residential area.

some water from the

reservoir diverted to

irrigational canal, dried

leaves & branches on

sides, grassy/vines

present on river banks,

residential area.

Other Observations fully covered w/ water

hyacinth, construction of

bridge on-going, high

water level, residential

area waste discharged

directly into the river.

transport area/used as

passage for people going to

the other side of the river,

high water level, few

garbage, no water hyacinth,

residential and commercial

area waste directly

discharged into the river,

port for motorized boat used

for dredging.

kangkong & other

vegetation,slight increase

in water width, garbage on

sides high water level,

residential area.


1580793

P 0328548

1579893

P 0329736

1577880

Table 2b.1.General Observation and Description of Sampling Stations

Stations Mouth of Sta Cruz riverSto Angel (Sta

Cruz, Laguna)

Pagsawitan

(Sta Cruz, Laguna)

Calumpang

(Liliw/Nagcarlan,

Laguna)

Sta Lucia

(Nagcarlan, Laguna)

Santa Cruz River (November Sampling)



27



Time 12:55 NN 1:08 PM 11:59 AM 11:30 AM 10:00 AM




Color clear clear clear clear clear


Weather Condition sunny sunny cloudy cloudy cloudy

water flows from the

tunnel and under the

boulders, washing area,

dried leaves, an increase

in water level, residential

area.

vines covering some

areas, flowpipe for the

fishpond water still

collecting water from the

canal/river, garbage on

sides & water surface,

residential area.

Other Observations dried bamboo poles &

leaves on sides, wider

range river width, high

water level, residential

area.

grassy area, high water

level, boulders no longer

seen, fishing activity on

other sides.

no garbage, a slight

increase in water level.

Residential area, river

water used for

bathing/washing.

P 0329720

1560074

P 0327773

1560676

StationsBrgy. Bancoro

(Nagcarlan, Laguna)


1567064

P 0329238

1563630

P 0329270

1563038

Brgy. Palina (Liliw,

Laguna)

Brgy. Balinacon

(Nagcarlan, Laguna)

Brgy. San Francisco

(Nagcarlan, Laguna)

Brgy. Pook (Rizal,

Laguna)

Table 2b.2. General Observation and Description of Sampling Stations




28



Time 10:15 AM 3:25 PM 3:15 AM 12:15 NN 2:30 PM




Color clear/greenish clear clear greenish clear


Weather Condition sunny to partly cloudy sunny sunny cloudy w/ rainshowers sunny

high water level, fishing

activity by hook and line,

few kangkong on sides,

boulders no longer seen,

water strider (Gerris sp .)

present on sides,

grassy/cogon on both

sides of the river banks.


1561843

leaves/bamboo poles

along the center of the

river, bulk of dried leaves,

water depth high,

grassy/vines along the

sides, left side of the river

bank goat/rooster farm, 2

outlet/pipes of spring

water flow into the river.

Other Observations area for picnic, water used

for bathing and washing

clothes, some area

converted on pools for

swimming/diving,

residential and resort

area.

residential area, domestic

waste directly discharged

into the river, absence of

birds, trees on sides, high

water level.

w/ garbage on sides,

residential area, dried

leaves on sides.

P 0332779

1563381

P 0332430

1563198

Brgy. Palayan

(Nagcarlan, Laguna)

Brgy. Cabuyew (Liliw,

Laguna)

Table 2b.3. General Observation and Description of Sampling Stations


P 0327511

1563348

P 0328852

1566677

StationsBrgy. Laguan

(Nagcarlan, Laguna)

Brgy. Panglan

(Majayjay, Laguna)

Brgy. Ibabang San

Roque (Liliw, Laguna)



29

Table 3a. Physico-Chemical Parameters of Santa Cruz River (May 2011)

Station 1 Station 2 Station 3 Station 4 Station 5 Station 6 Station 7 Station 8 Station 9 Station 10 Station 11 Station 12 Station 13 Station 14 Station 15DENR Class C

WQ Criteria

pH, units 6.5 6.6 6.8 7.0 6.8 7.4 6.7 6.4 5.8 6.5 6.7 6.5 6.4 7.0 6.8 6.5 - 8.5

Total Suspended Solids, mg/L 4 8 8 5 11 6 11 10 1 7 9 0.5 0.5 9 7 <30 (increase)

Total Dissolved Solids, mg/L 230 222 216 192 237 241 145 148 149 221 228 132 183 254 173 1000

Total Solids, mg/L 234 230 224 197 248 247 156 158 150 228 237 132 183 263 180

Chemical Oxygen Demand, mg/L 20 26 20 12 27 8 12 12 8 8 16 16 20 14 24

Biochemical Oxygen Demand, mg/L 4 6 3 1 5 1 1 2 1 1 2 2 4 2 4 10

Dissolved Oxygen, mg/L 5.4 6.2 6.9 7.6 5 8.3 8 8 7.2 7.2 7.5 8.3 6 7.7 7.8 5(minimum)

Oil/Grease, mg/L 3 2 2 2 2 4 3 3 2 2 2 2 2 4 4 2

Ammonia, mg/L 0.2993 0.0709 0.4302 0.0291 0.9884 0.0364 0.0223 0.0302 0.1620 0.4700 0.0248 0.0149 0.7441 0.0412 0.0818

Nitrate, mg/L 0.5808 0.6448 0.6611 0.9938 0.0929 0.7669 1.0124 1.0304 1.0870 1.4144 1.4700 0.6029 0.6907 0.4094 1.0298 10

Inorganic Phosphate, mg/L 0.418 0.3664 0.3199 0.4271 0.6331 0.3741 0.2263 0.2295 0.5027 0.4007 0.4092 0.0904 0.5134 0.2584 0.4206 0.4

Total Phosphorus, mg/L 0.622 0.5307 0.397 0.546 1.003 0.3792 0.2376 0.2295 0.5027 0.4656 0.4918 1.2544 0.7294 0.2584 0.6018

Total Nitrogen, mg/L 6.6 5 6 3.7 8 3.5 4.6 3.7 6.1 4.6 5.4 4.1 5.8 3.8 4.8

Chloride, mg/L 19 19 19 15 15 15 11 11 11 11 11 15 11 37 11 350

Alkalinity, mg/L 132 124 120 100 156 136 64 60 52 116 116 48 80 108 84

Calcium Hardness, mg/L 48 48 44 36 56 44 28 24 16 40 32 20 32 48 32

Total Hardness, mg/L 108 104 96 80 128 116 52 44 44 92 96 32 60 100 64

Turbidity, NTU 7 7 13 5 6 4 2 2 <1 1 2 1 3 2 6

Conductivity µS/cm 331 312 292 246 361 337 159 152 150 288 298 114 192 372 192



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Table 3b. Physico-Chemical Parameters of Santa Cruz River (November 2011)

Station 1 Station 2 Station 3 Station 4 Station 5 Station 6 Station 7 Station 8 Station 9 Station 10 Station 11 Station 12 Station 13 Station 14 Station 15DENR Class C

WQ Criteria

pH, units 7.4 7.6 7.7 8.4 7 7.6 8.7 8 7 7.5 7.8 8.2 7.8 8.2 7.5 6.5 - 8.5

Total Suspended Solids, mg/L 14 11 21 10 15 11 7 8 0.5 10 11 0.5 7 26 11 <30 (increase)

Total Dissolved Solids, mg/L 150 154 169 184 241 235 156 151 159 241 229 79 132 218 154 1000

Total Solids, mg/L 180 230 224 197 248 247 156 158 150 228 237 132 183 263 180

Chemical Oxygen Demand, mg/L 52 4 2 12 2 2 24 12 4 2 16 2 2 2 2

Biochemical Oxygen Demand, mg/L 3 1 2 2 2 1 1 1 1 2 2 1 1 3 2 10

Dissolved Oxygen, mg/L 5.2 6.7 7.6 7.4 7.5 7.9 7.8 6.8 8.1 7.2 10.9 8 7.1 7.6 7.5 5(minimum)

Oil/Grease, mg/L 0.5 0.5 0.5 0.5 0.5 0.5 2 0.5 0.5 0.5 0.5 1 0.5 0.5 0.5 2

Ammonia, mg/L 0.1532 0.1005 0.0840 0.0805 0.0785 0.0587 0.0676 0.1116 0.1110 0.0874 0.0753 0.0831 0.1810 0.1014 0.0644

Nitrate, mg/L 0.9586 0.7421 0.9630 0.9093 0.5722 0.8676 1.3254 1.2670 1.2738 1.5224 1.5348 0.5062 0.3161 1.1041 0.1498 10

Inorganic Phosphate, mg/L 0.2375 0.2304 0.2205 0.323 0.2336 0.3211 0.1767 0.1673 0.3847 0.373 0.3528 0.001 0.0988 0.6258 0.3489 0.4

Total Phosphorus, mg/L 0.4102 0.29 0.3118 0.4548 0.3072 0.3211 0.9164 0.2216 0.408 0.3732 0.4244 0.055 0.3718 0.3818 0.3888

Total Nitrogen, mg/L 5 5 5.9 3.9 7.9 3.6 4.5 3.5 6 4.5 5 4.6 5.9 3.5 5

Chloride, mg/L 15 15 11 11 7 15 11 7 11 11 11 7 11 11 11 350

Alkalinity, mg/L 80 80 84 96 132 136 64 56 56 108 108 40 64 92 76

Calcium Hardness, mg/L 52 44 56 28 56 44 32 28 16 44 52 24 28 48 24

Total Hardness, mg/L 68 64 68 84 116 112 60 56 52 96 92 28 80 84 64

Turbidity, NTU 13 13 16 5 11 4 2 2 <1 1 3 1 4 9 4

Conductivity µS/cm 144 148 154 165 230 237 117 128 128 232 238 49 112 202 134



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Table 4a. Water Quality Assessment of Santa Cruz River and tributary based on Algal population (May 2011).

Stations Location Counts (organism/sq.m.) % Contribution Water Quality Assessment CWA PWA OTHERS TOTAL % CWA % PWA % OTHERS

Mainstream

1 mouth of Sta Cruz 0 2325 11628 13953 0.0 16.7 83.3 Moderately Polluted

2 Brgy. Sto Angel, Sta Cruz 5550 73252 19979 98781 5.6 74.2 20.2 Polluted

3 Brgy. Pagsawitan, Sta Cruz 789 5526 13420 19735 4.0 28.0 68.0 Moderately Polluted

4 Brgy. Calumpang, Nagcarlan 5167 9472 5167 19806 26.1 47.8 26.1 Polluted

Tributaries

5 Brgy. Sta Lucia, Nagcarlan 2870 10047 3590 16507 17.4 60.9 21.7 Polluted

6 Brgy. Bancoro, Nagcarlan 26049 137353 71834 235236 11.1 58.4 30.5 Polluted

7 Brgy. Palina, Liliw 29207 79727 22103 131037 22.3 60.8 16.9 Polluted

8 Brgy. Balinacon, Nagcarlan 2476 10729 0 13205 18.8 81.2 0.0 Polluted

9 Brgy. San Francisco, Nagcarlan 1651 825 4952 7428 22.2 11.1 66.7 Moderately Polluted

10 Brgy. Pook, Rizal 8181 31359 6135 45675 17.9 68.7 13.4 Polluted

11 Brgy. Laguan, Nagcarlan 0 897 0 897 0.0 100.0 0.0 Polluted

12 Brgy. Panglan, Majayjay 2583 3444 0 6027 42.9 57.1 0.0 Moderately Polluted

13 Brgy. Ibabang San Roque, Liliw 1651 14854 9903 26408 6.3 56.2 37.5 Polluted

14 Brgy. Palayan, Nagcarlan 4485 19734 8970 33189 13.5 59.5 27.0 Polluted

15 Brgy. Cabuyew, Liliw 27125 77610 30892 135627 20.0 57.2 22.8 Polluted



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Table 4b. Water Quality Assessment of Santa Cruz River and tributary based on Algal population (November 2011).

Stations Location Counts (organism/sq.m.) % Contribution Water Quality Assessment CWA PWA OTHERS TOTAL % CWA % PWA % OTHERS

Mainstream

1 Mouth of Sta Cruz 0 10941 2432 13373 0.0 81.8 18.2 Polluted

2 Brgy. Sto Angel, Sta Cruz 1110 2220 6660 9990 11.1 22.2 66.7 Moderately Polluted

3 Brgy. Pagsawitan, Sta Cruz 1110 1110 0 2220 50.0 50.0 0.0 Moderately Polluted

4 Brgy. Calumpang, Nagcarlan 1579 1579 2367 5525 28.6 28.6 42.8 Moderately Polluted

Tributaries

5 Brgy. Sta Lucia, Nagcarlan 718 718 7176 8612 8.3 8.3 83.3 Moderately Polluted

6 Brgy. Bancoro, Nagcarlan 1163 4651 0 5814 20.0 80.0 0.0 Polluted

7 Brgy. Palina, Liliw 0 18945 5526 24471 0.0 77.4 22.6 Polluted

8 Brgy. Balinacon, Nagcarlan 0 718 718 1436 0.0 50.0 50.0 Polluted

9 Brgy. San Francisco, Nagcarlan 6603 2476 0 9079 72.7 27.3 0.0 Clean

10 Brgy. Pook, Rizal 0 754 0 754 0.0 100.0 0.0 Polluted

11 Brgy. Laguan, Nagcarlan 3445 12056 861 16362 21.1 73.7 5.3 Polluted

12 Brgy. Panglan, Majayjay 682 2727 0 3409 20.0 80.0 0.0 Polluted

13 Brgy. Ibabang San Roque, Liliw 646 1292 646 2584 25.0 50.0 25.0 Polluted

14 Brgy. Palayan, Nagcarlan 1508 2261 1508 5277 28.6 42.8 28.6 Polluted

15 Brgy. Cabuyew, Liliw 5525 9473 3946 18944 29.2 50.0 20.8 Polluted



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Water Quality

CWI MPWI PWI Others Total %CWI %MPWI %PWI %Others Assessment

Mainstream

Stn. 1 Mouth of Sta. Cruz 0 1620 0 0 1620 0.00 100.00 0.00 0.00 Moderately Polluted

Stn. 2 Sto. Angel 0 5517 0 48 5565 0.00 99.14 0.00 0.86 Moderately Polluted

Stn. 3 Pagsawitan 22 855 133 0 1010 2.18 84.65 13.17 0.00 Moderately Polluted

Stn. 4 Calumpang 100 22 44 0 166 60.24 13.25 26.51 0.00 Clean Water

Tributaries

Stn. 5 Sta. Lucia 0 144 100 67 311 0.00 46.30 32.15 21.54 Moderately Polluted

Stn. 6 Bancoro 0 2110 33 33 2176 0.00 96.97 1.52 1.52 Moderately Polluted

Stn. 7 Palina 221 122 66 11 420 52.62 29.05 15.71 2.62 Clean Water

Stn. 8 Balinacon 88 44 0 0 132 66.67 33.33 0.00 0.00 Clean Water

Stn. 9 San Francisco 11 11 166 22 210 5.24 5.24 79.05 10.48 Polluted

Stn. 10 Pook 11 11 33 11 66 16.67 16.67 50.00 16.67 Polluted

Stn. 11 Laguan 88 110 44 0 242 36.36 45.45 18.18 0.00 Moderately Polluted

Stn. 12 Panglan 134 0 22 22 178 75.28 0.00 12.36 12.36 Clean Water

Stn. 13 Ibabang San Roque 22 55 11 156 244 9.02 22.54 4.51 63.93 Moderately Polluted

Stn. 14 Palayan 177 110 33 11 331 53.47 33.23 9.97 3.32 Clean Water

Stn. 15 Cabuyew 33 99 0 467 599 5.51 16.53 0.00 77.96 Moderately Polluted

Stations

Counts (no. of organisms/sq.m.) Percentage Contribution

Table 5a. Water Quality Assessment of Santa Cruz River based on Benthic Macroinvertebrates (May)



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Water Quality

CWI MPWI PWI Others Total %CWI %MPWI %PWI %Others Assessment

Mainstream

Stn. 1 Mouth of Sta. Cruz 0 2049 0 0 2049 0.00 100.00 0.00 0.00 Moderately Polluted

Stn. 2 Sto. Angel 0 931 28 0 959 0.00 97.08 2.92 0.00 Moderately Polluted

Stn. 3 Pagsawitan 0 99 0 0 99 0.00 100.00 0.00 0.00 Moderately Polluted

Stn. 4 Calumpang 178 0 0 0 178 100.00 0.00 0.00 0.00 Clean Water

Tributaries

Stn. 5 Sta. Lucia 88 55 0 0 143 61.54 38.46 0.00 0.00 Clean Water

Stn. 6 Bancoro 0 0 11 11 22 0.00 0.00 50.00 50.00 Polluted Water

Stn. 7 Palina 33 78 11 0 122 27.05 63.93 9.02 0.00 Moderately Polluted

Stn. 8 Balinacon 33 55 11 0 99 33.33 55.56 11.11 0.00 Moderately Polluted

Stn. 9 San Francisco 0 22 11 0 33 0.00 66.67 33.33 0.00 Moderately Polluted

Stn. 10 Pook 66 0 11 0 77 85.71 0.00 14.29 0.00 Clean Water

Stn. 11 Laguan 33 11 11 0 55 60.00 20.00 20.00 0.00 Clean Water

Stn. 12 Panglan 55 22 0 0 77 71.43 28.57 0.00 0.00 Clean Water

Stn. 13 Ibabang San Roque 88 33 0 0 121 72.73 27.27 0.00 0.00 Clean Water

Stn. 14 Palayan 99 77 11 0 187 52.94 41.18 5.88 0.00 Clean Water

Stn. 15 Cabuyew 243 22 22 0 287 84.67 7.67 7.67 0.00 Clean Water

Stations

Counts (no. of organisms/sq.m.) Percentage Contribution

Table 5b. Water Quality Assessment of Santa Cruz River based on Benthic Macroinvertebrates (November)



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Total Coliform

MPN/100mL

Fecal Coliform

MPN/100mL

Detection of

E.coli

Total Coliform

MPN/100mL

Fecal Coliform

MPN/100mL

Detection of

E.coli

Station 1 8,000 8,000 present 160,000 54,000 present




Station 5 >16,000 >16,000 present 92,000 92,000 present




Station 9 <20 <20 not detected 330 170 present







May sampling November samplingSampling

stations

Table 6. Results of Microbiological Analysis (May and November sampling)



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Figure 16. Pictures of Santa Cruz River Stations

Station 1 (May sampling) Station 1 (November sampling)





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Documents

Water Quality Assessment - Laguna Lake …llda.gov.ph/dox/waterqualityrpt/rivers/StaCruz.pdfEngr. Jocelyn G. Sta Ana, OIC, Environmental Laboratory and Research Division For more information,