DIVINE WORD COLLEGE OF LAOAG

School of Engineering and Architecture

Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

CHAPTER I

INTRODUCTION

Background of the Study

Throughout our history, floods have been the most frequent and destructive type of

disaster, causing significant damage and disrupting livelihoods throughout the world.

Floods are usually caused by intense storms that produce more runoff than an area can store

or a stream can carry within its normal channel, it often happens over a flat or low-lying

area. The Philippines gets more of its share of floods compared to other countries due to

its location relative to the paths of typhoon.

In Laoag City, Ilocos Norte; there are areas affected by flood due to heavy storms

and rain. Every year, the city is always affected by flood, especially on urban areas. The

affected areas are mostly in the streets, houses, buildings, and public places. The recently

experienced typhoon “Ineng” had made a big impact on the lives of many people. The

typhoon was devastating resulting damages to structures, roads, and vehicles.

There is a wide range of flood management methods available that can reduce this

type of destruction. Drainage and Flood Risk Assessment on Flooded Areas is an effective

way to prevent this type of problem. The drainage assessment and flood assessment are

essential in land-use master planning, design of infrastructure, and emergency response

preparation. The assessment is intended to help/guide those involved in the installation of

drainage and water infrastructure through the necessary stages to obtain relevant

permissions and comply with standards and policies.

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

The target audience of this study are primarily those involved in the design and

management of water infrastructure in addition to planners. The assessment, however, does

not attempt to provide comprehensive coverage of all aspects of drainage and water

infrastructure design, nor to advise on the design of a development.

In carrying out the assessment, a step-by-step plan must be developed. The process

may appear to be large initially but should be straightforward for smaller developments.

Often, larger developments require more deliberation and there can be many co-planning

assessments, for example, an environmental statement and environmental impact

assessment. Typically, the larger the development, the greater the potential risk to the

environment and increased awareness of environmental impact from flooding. Poorly-

conducted assessments can lead to poor management decisions. On the other hand, well-

conducted assessments can provide valuable support for a range of decisions.

Statement of the Problem

1. What are the differences between the flood hazard map at the city planning and the

actual floods happening in Laoag City?

2. How will the flood hazard map can assist in managing floods?

3. What barangays are mostly affected by floods in Laoag City?

4. Are the drainage systems in Laoag City working properly?

5. What is the condition of flood on urban barangays in Laoag City?

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Objectives of the Study

General Objective

The primary objective of this study is to determine the areas in Laoag City that are

prone to flood and has lack of maintenance, for a well-developed preparedness.

Specific Objectives:

1. To update the flood hazard map in Laoag City.

2. To serve as a basic reference regarding flood awareness in Laoag City urban

areas.

3. To check and be updated if the existing drainage systems in Laoag City are still

working.

4. To give a general guide for developers on where to build structures.

Significance of the Study

The purpose of this assessment is essential to investigate, assess and advise on what

are the best solutions in reducing flood. The drainage and flood risk assessment on urban

barangays in Laoag City will have a significant impact on the development of projects

involving flood management. This study provides basic information for land use planning.

The planners, developers and most importantly the residents of Laoag City will benefit in

the development of these projects. It will lead to the creation of successful, sustainable,

liveable spaces and places that are functional. The city will be capable of delivering

services that people needs, including drainage all in line with a modern planning approach.

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

The study will also have an importance to the design of disaster preparedness, the

concerned organization will plan and undertake.

Scope and Delimitation of the Study

The study focuses only on the areas that are mostly affected by flood on the urban

barangays in Laoag City such as barangays near or far from the river, creeks and canals.

Regardless of the time limit, the assessment will still provide useful information through

observation, and interviews with the residents on urban barangays in Laoag City.

Definition of Terms

Drainage - is the natural or artificial removal of a surface's water and sub-surface

water from an area with excess of water.

Drainage Assessment – helps to identify sustainable methods for disposing of

waste water, draining surface water, and managing surface water flooding.

Drainage Canal – An artificial canal built to drain water from an area having no

natural outlet for precipitation accumulation.

Drainage System – is an arrangement to move liquids away from where they are

not required for disposal in appropriate locations. A ‘drainage system’ can include anything

from gutters and drains in houses to remove rain water, storm water systems to drain

rainwater from roads into roadside drains.

Flood – an overflowing of a large amount of water beyond its normal confines,

especially over what is normally dry land.

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Flood Hazard Map - is designed to increase awareness of the likelihood of

flooding among the public, local authorities and other organizations. They also encourage

people living and working in flood-prone areas to find out more about the local flood risk

and to take appropriate action.

Hazard - Natural process or phenomenon that may cause loss of life, injury or other

health impacts, property damage, loss of livelihoods and services, social and economic

disruption, or environmental damage.

Risk - The combination of the probability of an event and its negative

consequences. In this assessment, disaster risk is a factor of hazard, exposure and

vulnerability. Although the factors are not always totally independent, it helps the social

discussion and scientific analysis to differentiate the factors and what contributes to

increase or decrease each of their impacts to the overall risk.

Risk Assessment - A methodology to determine the nature and extent of risk by

analyzing potential hazards and evaluating existing conditions of vulnerability that together

could potentially harm exposed people, property, services, livelihoods and the environment

on which they depend.

Urban Area - an urban area or urban agglomeration, is a human settlement with

high population density and infrastructure of built environment. Urban areas are created

through urbanization and are categorized by urban morphology as cities, towns,

conurbations or suburbs.

Vulnerability - The characteristics and circumstances of a community, system or

asset that make it susceptible to the damaging effects of a hazard.

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

CHAPTER II

REVIEW OF RELATED LITERATURE

Local Literature

Flooding

Flooding in cities of developing countries is common, primarily due to poor

planning and project designing and execution. Factors causing floods are due to increase

population, outdated and non-functional drainage system, heavily silted and reduced river

size, poor waste management, no erosion control measures, reduced vegetative cover and

the unusually heavier precipitation (Ronald L. Orale, 2015).

Risk Assessment

Risk Assessment is the systematic and logical process used to determine disaster

risk reduction priorities by evaluating and comparing the levels of risk (high or intolerable,

medium or tolerable, low or minimal). This comprises the process by which individuals,

communities and societies cope with hazards. Disaster risk assessment deals with the

Hazard, Vulnerability and Capacity Assessment (HVCA) and people’s perceptions of risks.

The researchers have already slightly touched on HVCA. The implication that is observed

by the two DRRM analysts is that disaster risk will be based on people’s perception. Thus,

they will be the one to make decisions to adapt, to modify or to ignore the risk (Lomerio-

Ondiz & Redito, 2009).

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Disaster Preparedness

Dr. Rene N. Rollon (2010), Associate Professor and Director, Institute of

Environmental Science and Meteorology, U.P. Diliman, has a view on disaster

preparedness which is much more realistic. He averred that, on the management side,

prevention is always an ideal strategy. For instance, human settlements in coastal areas

should be avoided unless some aggressive measures are in place (high and expensive dikes,

retaining walls, etc.). Obviously, such incongruence between natural processes and the

human use of physical resources have been demonstrated on many occasions. Indeed,

especially for urban centers like Metro Manila, preventive measures (e.g. relocation, job

generation, easement areas, no settlement zones, etc.) may be very expensive. However,

the annual cost of lives and properties attributed to the “disrespect” for these natural

processes is not cheap either, and, is, in fact increasingly frustrating.

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Local Studies

Flood Risk and Resilience Assessment

This study proposes a measurement and evaluation approach for community

resilience to flood disasters using a set of biophysical and socioeconomic indices. It

identifies geographic and thematic areas where policy interventions are most critical. The

study applies this approach in selected barangays (the smallest administrative units) in the

Santa Rosa-Silang sub-watershed in the Laguna Lake region of the Philippines. Results

suggest that in order to enhance resilience, it is necessary to strengthen the institutional

capacity of barangays to formulate and implement disaster risk reduction initiatives as a

legitimate part of their overall land-use-based development plans. Disaster risk reduction

initiatives should place equal attention on both ex ante and ex post measures. Ex

ante measures include putting in place regular community disaster awareness and

preparedness programs that would emphasize the cost of a disaster, the value of

participation and volunteerism, as well as livelihood and savings formation. Ex

post measures include enhancing the capabilities of emergency facilities and services by

providing permanent and volunteer personnel with regular training and equipment.

Resource constraints could be addressed by maximizing strong linkages between local

government units, academics and non-governmental organizations to enable financial,

material, and knowledge transfer. Bridging institutional relationships with

nearby barangays and strengthening their bonds with local networks of residents, leaders,

and organizations may also help to spread the cost of reducing disaster risk and to promote

resilience (M.A. Cuesta et al. 2014).

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Socio-economic Impacts of Storm

Tropical storm Washi wrenched the spotlight to the wave of hydro-meteorological

phenomena that appear increasingly ferocious. Due to catastrophic floods damage, tropical

storm Washi was marked as the most destructive tropical cyclone in the Philippines and

the world's second most deadly disaster of 2011. The Washi disaster was reminiscent of

the Ormoc tragedy in 1991 and recalled images of the Fukushima tsunami disaster in March

2011. Entire villages were washed away when Washi whipped south Philippines in early

hours of the day, leaving a trail of flattened homes, broken bridges and upended vehicles

in the poverty-stricken country.

The overall numbers of casualties included 1,292 deaths, 1,049 missing and 2,002 injured.

A total number of 695,195 people (110,806 families) were affected. The highest number

of casualties was reported in CDO and Iligan City.

Water reached formal and informal settlements at a height of 9-10 meter. Totally 39,558

houses were destructed, among them 11,463 houses totally damaged and 5% were formally

owned. The damage to infrastructure and agriculture amounted to be 25,488,740,129 USD

(P1.082B). For the overall socio-economic impacts, the estimated cost of damage to

properties is amounted to 97,847,468.65 USD (Nathaniel T. SERVANDO, 2012).

Early Warning and Emergency Response

a. National and Regional Preparedness

As early as December 13, 2011, three days prior to the entry of TS Washi in the Philippine

Area of Responsibility (PAR), Philippines National Disaster Risk Reduction and

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Management Council (NDRRMC) was already activated and raised to “Blue Alet Status.

The “Duty Alert” System was immediately implemented. Agencies preparedness measures

were the following:

1) PAGASA issued the first advisory of TS Washi on the 14th of December and

continuously provided NDRRMC with 15 Severe Weather Bulletins on Tropical Storm

"SEN-DONG"; General Flood Advisories and Gale Warnings; detailed its personnel round

the clock at the NDRRMC for prompt coordination with their bureau especially with the

Weather Forecasting Section, Weather Division; continuously tracked the development

and movement of TS Washi prior to and upon its entry in the PAR as well as its landfall;

and conducted series of press conferences.

2) NDRRMC OPCEN subsequently issued NDRRMC Advisories to areas likely to be hit

by TS Sendong through SMS and facsimile for further dissemination to their respective

local DRRMCs from the provincial down to the Barangay levels and uploaded same

advisories at the NDRRMC Website, Facebook, and Twitter accounts for the general

public.

3) NDRRMC Executive Director issued directive to the RDRRMCs concerned through the

Office of Civil Defense Regional Centers (OCDRCs) to undertake precautionary measures

in their respective AORs and subsequent issuance of advisories to the local DRRMCs to

initiate pre-emptive evacuation of population in low-lying and mountainous areas if

situation warrants.

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

4) All agencies such as Department of Social Welfare and Development (DSWD),

Department of Health (DOH), Department of Education (DepED), The Armed Forces of

the Philippines (AFP) The Philippine Department of the Interior and Local Government

(DILG), the Philippine National Police (PNP), Bureau of Fire Protection (BFP), The

Philippine Coast Guard (PCG), The Philippines' Department of Public Works and

Highways (DPWH) and the National Grid Corporation of the Philippines (NGCP) had

provided directions to the Heads of their respective local Offices in the regions to

undertake preparedness initiatives such as activation of respective OPCENs, alerting of

emergency responders, prepositioning of resources (relief supplies, equipment and

manpower) and conduct of pre-emptive evacuation of residents at the low lying and

flood/landslide prone areas through issuance of Memoranda/directives.

5) RDRRMCs/OCDRCs and local agencies concerned replicated the same actions at the

local level in compliance with the directions provided by their national offices.

b. Emergency Response

A series of emergency response were taken right after the disaster by Philippine national

and local governments, nongovernment organizations and international organizations:

1) NDRRMC spearheaded by the Executive Officer, NDRRMC, and the RDRRMCs

concerned spearheaded by the OCD Regional Directors conducted various emergency/

coordination meetings for the issuance of directives to the member agencies in the

execution of appropriate responses as well as discussion of issues and concerns on the

consequences of the prevailing disaster.

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

2) USEC RAMOS immediately proceeded to OCD/RDRRMC X and spearheaded the

conduct of ocular inspection in the affected areas, assessment of immediate needs,

mobilization of resources (equipment and personnel), conduct of survey and monitoring,

continuous provisions of the basic needs to the affected and displaced population. OCD

provides Household Starter Kits to families moving to the permanent relocation sites.

There is also a construction of Multi-Purpose Community Centers and schools set up in all

relocation sites.

3) RDRRMC and Local DRRMCs Chairpersons likewise orchestrated their disaster

operations in their respective areas of responsibility. Local Government Units (LGUs) in

coordination with the local AFP, PNP, PCG delivered other basic services such as transport

of relief goods by land, air and water and distribution to the disaster-stricken regions.

4) Non-Government Organizations and international organizations also took active rescue

operation. The Camp Coordination and Management (CCM) and NFI cluster provided

emergency shelter, co-chaired by International Organization for Migration (IOM) which

also aims to provide emergency shelter repair kits and other NFIs to the displaced families.

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

CHAPTER III

METHODOLOGY

This chapter consists of the procedures in conducting the assessment. The assessment

methodology consists of three main steps:

Research Flow Diagram

START

Data Gathering

Analyzing the Data

Assessment Report

End

I. Data Gathering - In this step the researcher perform data gathering such as document

review, and observation. This is where the researcher started to explore existing projects

and gather updated information on the current situation of the urban areas in Laoag City.

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

II. Analyzing the Data - The collected data will be used to determine and document the

strength and areas to be improved.

III. Assessment Report - An assessment report will be made using the results from the

previous steps as a guide. The assessment report documents the data collected and provides

a discussion on how it relates to each attribute or criterion.

Research Design

The flood risk assessment is a descriptive type of study. It means to identify the

level of risk in a certain place. The result of the assessment will be used to identify actions

to be taken before and during flood. The study focuses on assessing the flooded areas in

Laoag City.

Sources of Data

The source of data in this study is composed of the people who experienced flood

in Laoag City. There are thirty (30) urban barangays in Laoag City. Five (5) respondents

per barangay for residential for a total of one hundred fifty (150) will be handed

questionnaires.

Data Gathering Procedure

The researcher first asked a permission to higher authorities of Laoag City to have

a copy of the flood risk map that will be used for basis in the assessment. Data can be

collected by using questionnaires and performing an interview to the respondents.

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Instruments in Data Collection

Questionnaire

A series of questions will be asked to the residents in Laoag City, the questions are

about the recent floods that happened, and how it affected them. Survey questionnaires will

be administered to 5 respondents per barangay.

Observation

Observation is the most fruitful method of data collection because it reduces the

chances of recording incorrect data by respondents.

Measurement

The canals will be measured using measuring tools such as tape measure. It's a tool

with enough length for measuring extended spans but not too long that's it's heavy and

unwieldy to use for shorter measurements. It will be used in assessing drainage by

measuring canals length, width, and depth.

Analyzing the Data

The data gathered will be subjected to an analysis and interpretation. The

descriptive method will be used in the presentation of data analysis from the responses

generated from the questionnaires.

The open-ended questions that will be given in the interview will shed light on the

prevailing issues and concerns of the barangay people on flood risks and will be utilized to

interpret significant data generated from the research study.

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

CHAPTER IV

DATA PRESENTATION, ANALYSIS AND RESULTS

This chapter contains detailed presentation and discussion of data analysis and the

results of this study.

Overview of Data Collected

The Table 1 presents the details of the data that has been collected for the “Drainage and

Flood Risk Assessment on Flooded Urban Barangays in Laoag City”.

Table 1: Overview of the Date collected for Drainage and Flood Risk Assessment in Laoag

City.

Data Type Parameters Source/Remarks

Climatology data Rainfall rate Weather Website
Hydrological data Water level (flood plain) Questionnaire Survey

Cross sectional data N/A Field Survey

Social Data Length of residence with Questionnaire Survey
this community
Physical Data Location of the house Questionnaire Survey
Distance of the house from
flood
Exposure Data -Household understands Questionnaire Survey
warning
-Households experienced
food damages in past

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Questionnaire Survey for Drainage and Flood Risk Assessment

Overview of the questionnaire survey

The core objective of the questionnaire survey was to collect the primary data on

flood risk assessment in the target area (Figure 1) and evaluate the degree of risk on urban

areas of Laoag City.

Target Area of the Assessment

The Target Area is composed of 30 flooded urban barangays in Laoag City.

Figure 1: Target Area, Laoag City, Ilocos Norte

Source: www.google.com/maps

A survey questionnaire was designed based on the land use characteristics in the

study area in order to capture all the essential information. For details of the questionnaire

survey form, please see Appendix B.

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Table 2: List of Flooded Barangays in Laoag City.

Barangay Number Name

1 San Lorenzo
2 Santa Joaquina
3 Nuestra Señora del Rosario
4 San Guillermo
5 San Pedro
6 San Agustin
7-A Nuestra Señora del Natividad
7-B Nuestra Señora del Natividad
8 San Vicente
9 Santa Angela
10 San Jose
11 Santa Balbina
12 San Isidro
13 Nuestra Señora de Visitacion
14 Santo Tomas
15 San Guillermo
16 San Jacinto
17 San Francisco
18 San Quirino
19 Santa Marcela
20 San Miguel
21 San Pedro
22 San Andres
23 San Matias
24 Nuestra Señora de Consolacion
25 Santa Cayetana
26 San Marcelino
27 Nuestra Señora de Soledad
28 San Bernardo
29 Santo Tomas

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Length of Residency

A total of 150 respondents were handed questionnaires uniformly across the study

area. However, only 136 questionnaires were retrieved from the respondents. The samples

were taken from houses on flooded urban barangays in Laoag City. The year of residency

of respondents is shown in Table 3.

Table 3: Length of Residency of Respondents in Laoag City.

Year Range No. of Respondents Percentage

0-10 years 3 2.21%
11-20 years 22 16.18%
21-30 years 25 18.38%
31-40 years 34 25.00%
41-50 years 26 19.12%
51 years and up 26 19.12%

Number of Times Respondents Experienced Flood in their Address

Table 4 shows the number of times the respondents experienced flood in their

address. Among the respondents, 55.88% experienced flood many times living in their

address. 38.24% were affected from flood 1-5 times, and 5.88% were not affected by flood.

Upon talking with the respondents that never experienced flood, some have given an

information about the flooded areas in their barangay and nearby their barangays. It implies

that the majority of the respondents were affected by flood.

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Table 4: No. of Times Respondents Experienced Flood in their Address.

Times Flooded No. of Respondents Percentage

Never 8 5.88%
1-5 times 52 38.24%
Many times 76 55.88%

Sources of Flooding

As shown in Table 5, The respondents have given an information about the sources

of flooding, most of them are concerned about the heavy rain pours with a percentage of

68.38%, followed by the canals with a percentage of 26.47%. Some are concerned about

the river, creeks, irrigation, and others. It implies that the majority of the respondents are

concerned in any sources of flooding.

Table 5: Sources of Flooding.

Sources of Flooding No. of Respondents Percentage

River 11 8.09%
Creek 11 8.09%
Canal 36 26.47%
Irrigation 3 2.21%
Heavy rain pours 93 68.38%
Others 7 5.15%
None 3 2.21%

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Distance of Property to Any Potential Source of Flood

Most of the respondents are far from any potential source of flood with a percentage

of 62.50%, while the respondents near sources of flood are over 37.50%.

Table 6: Distance of Property to Any Potential Source of Flood

Distance Respondents Percentage

Near 51 37.50%
Far 85 62.50%

Awareness in Response to Flooding

Table 7 shows the awareness of the respondents in response to flooding. 77.94%

were aware of the flood hazard map. The researcher discussed what is flood hazard map to

the remaining respondents that were not aware. All of the respondents were aware of the

disaster warning system in the city. 86.76% were aware that their house is at risk of

flooding. 21.32% of the respondents were participating in the local drills. 96.32% think

that their community has the necessary information and resources to be ready if flooding

occurs. 85.29% were prepared to deal with the flooding events. 97.79% believed that the

involvement of their community in responding to flooding with the assistance of other

public services is important. It implies that the majority of the respondents were aware in

response to flooding and prepared to deal with the flooding events regardless that most of

them did not participate in local drills conducted by the barangays or the city.

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Table 7: Awareness in Respond to Flooding.

AREA OF ANSWERED ANSWERED ANSWERED ANSWERED

CONCERN YES NO YES% NO%
Are you aware of the 106 30 77.94% 22.06%
flood hazard map?
Are you aware of the 136 0 100% 0%
disaster warning
system in Laoag
City?
Are you aware that 118 18 86.76% 13.24%
your home is at risk
of flooding?
Are you 29 107 21.32% 78.68%
participating in the
local drills
conducted by the
city or barangay?
Do you think your 131 5 96.32% 3.68%
community has the
necessary
information and
resources to be ready
if flooding occurs?
Are you prepared to 116 20 85.29% 14.71%
deal with the
flooding events?
Do you believe that 134 2 97.79% 2.21%
the involvement of
your community in
responding to
flooding with the
assistance of other
public services is
important?

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

The respondents were aware that flooding might reach their home. All of the

respondents were well-informed through TV, radio, newspaper, siren, telephone, face to

face by public workers, face to face by others, observing the water levels, and other sources,

for example: social media. The top 3 sources of information are through TV, radio and

siren.

Table 8: Sources of Information

Sources No. of Respondents Percentage

TV 102 75.00%

Radio 57 41.91%

Newspaper 6 4.41%

Siren 49 36.03%

Telephone 2 0.74%

Face to face by public 2 1.47%

workers

Face to face by others 3 2.21%

Observing the water levels 3 2.21%

Other 2 1.47%

23
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Measures Taken to Prevent the House from Flood

The respondents attempted to prevent flood from their houses. Most of the

respondents did nothing, some used temporary barriers, and other ways to prevent flood to

enter their houses.

Table 9: Measure taken to prevent the house from flood.

Measure Taken No. of Respondents Percentage

Pumped 0 0

Temporary Barriers 8 5.88%

Did Nothing 112 82.35%

Other ways 16 11.76%

Maximum Water Level and Duration of Flood

Some of the respondents gave information about the maximum level of water that

entered their house. The maximum level water that entered their building was 0.35m. The

highest level of water a respondent experienced was 8 ft. that lasted in 2 days on Barangay

7-B, Laoag City. It happened Last August, 2019 caused by the Typhoon Ineng.

24
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Government Response Before, During and After Flooding Events

Table 10 shows the percentage of responsiveness of the government. It implies that

the government is very responsive in all aspects when it comes to flooding events.

Table 10: Government Response, before, during, and after flooding events.

Area of No. of Respondents Percentage

Concern Not Slightly Responsive Not Slightly Responsive
Responsive Responsive Responsive Responsive

Evacuation 17 119 12.50% 87.50%

Procedure
Disaster 15 121 11.03% 88.97%
Warning
System
Provision 24 112 17.65% 82.35%
of
Temporary
Shelter
Provision 28 108 20.59% 79.41%
of
Necessities
Relief 25 111 18.38% 81.62%
Operation
Search and 2 17 117 1.47% 12.50% 86.03%
Rescue

25
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Drainage System in Laoag City

Figure 3: Drainage System Layout.

Source: Self-made Map by The Researcher

26
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Cross-section of the Drainage System in Laoag City

Figure 4: Cross-section of the Main Drainage to River Dike.

Source: Field Survey

Figure 5: Cross-section of the Secondary Drainage.

Source: Field Survey

27
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Average Rainfall Rate

Figure 6: Monthly Average Rainfall Rate

Source: www.weather-and-climate.com

Average rainfall in January: 11.8mm Average rainfall in July: 386.4mm

Average rainfall in February: 1.1mm Average rainfall in August: 547.3mm

Average rainfall in March: 2.5mm Average rainfall in September: 324.1mm

Average rainfall in April: 19.8mm Average rainfall in October: 86.1mm

Average rainfall in May: 125.1mm Average rainfall in November: 45.1mm

Average rainfall in June: 376.8mm Average rainfall in December: 10.2mm

28
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Computation of Drainage

Flow rate from rainfall which is computed using rational method is compared to

the design flow rate from the drainage’s service area computed using manning’s formula.

If the design flow rate is lower than the actual flow rate, the drainage canal will be

redesigned using its most efficient section.

Rational Method for Flow Rate

Q= CiA

Where:

C = Runoff Coefficient i = Average Rainfall Rate

C = 0.825 for Concrete Pavement i = 2.04x10-6 m/s

Table 11: Length and Area of the Drainage System in Laoag City.

Code Street Length Area

MD1 J.M Guerrero St. 150.78m 11,701.54m2
MD2 Ablan Avenue 1,800m 51,770.33m2
MD3 Hernando St. 1,200m 59,803.82m2
MD4 V. Llanes St. 845.80m 34,321.15 m2
MD5 M. Nolasco St. 206.25m 14,906.84 m2
MD6 Abadilla St. 192.12m 13,092.43 m2
MD7 F. Guerrero 220.30m 13,060.15 m2
MD8 J. M. Basa St. 220.00m 14,308.62 m2
MD9 Lincoln St. 776.36 44,094.90 m2
MD10 Soliman St. 946.25m 91,092.26m2
MD11 F.R. Castro St. 176.20m 24,085.64 m2
MD12 G. Tamayo St. 100.00m 3,509.90 m2

29
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Code Street Length Area

SD1 J.P. Rizal St. 820.00m 79,536.96m2
SD2 Primo Lazaro St. 1,270m 197,755.55m2
SD3 D. Samonte St. 880.00m 121,974.00m2
SD4 Gomburza St. 285.00m 41,306.33m2
SD5 A. Mabini St. 237.00m 29,920.64m2
SD6 P. Gomez St. 940.00m 121,962.72m2
SD7 Gov. Agbayani St. 720.00m 27,3721.21m2
SD8 Lagasca St. 240.00m 9,060m2
SD9 S. Mandac St. 150.00m 11,165.00m2
SD10 E. Jacinto St. 80.00m 5,700m2
SD11 Paterno St. 185.00m 11,270.57m2
SD12 J. P. Rizal St. 480.00m 25,500m2
SD13 T. Pasion St. 1,070.00m 128,336.98m2
SD14 M.H. Del Pilar St. 1,060.00m 128,071.93m2
SD15 J. P. Rizal St. 720.00m 54,031.28m2
SD16 P. Gomez St. 900.00m 140,800.00m2
SD17 Maria Dizon St. 960.00m 86,543.91m2
SD 18 F. R. Castro St. 720.00mm 27,3721.21m2
Source: www.google.com/maps

30
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Q = CiA

Main Drainage

MD1 = Q1 = (0.825)( 2.04x10-6)( 11701.54) = 0.02 m3/s

MD2 = Q2 = (0.825)( 2.04x10-6)( 51770.33) = 0.09 m3/s

MD3 = Q3 = (0.825)( 2.04x10-6)( 59803.82) = 0.10 m3/s

MD4 = Q4 = (0.825)( 2.04x10-6)( 34321.15) = 0.06m3/s

MD5 = Q5 = (0.825)( 2.04x10-6)( 14906.84) = 0.03 m3/s

MD6 = Q6 = (0.825)( 2.04x10-6)( 13092.43) = 0.02 m3/s

MD7 = Q7 = (0.825)( 2.04x10-6)( 13060.15) = 0.02 m3/s

MD8 = Q8 = (0.825)( 2.04x10-6)( 14308.62) = 0.02 m3/s

MD9 = Q9 = (0.825)( 2.04x10-6)( 44094.9) = 0.07 m3/s

MD10 = Q10 = (0.825)( 2.04x10-6)( 91092.26) = 0.15 m3/s

MD11 = Q11 = (0.825)( 2.04x10-6)( 24085.64) = 0.04 m3/s

MD12 = Q12 = (0.825)( 2.04x10-6)( 3509.9) = 0.01 m3/s

31
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Secondary Drainage

SD1 = Q13 = (0.825)( 2.04x10-6)( 79536.96) = 0.13 m3/s

SD2 = Q14 = (0.825)( 2.04x10-6)( 197755.55) = 0.33 m3/s

SD3 = Q15 = (0.825)( 2.04x10-6)( 121974) = 0.21 m3/s

SD4 = Q16 = (0.825)( 2.04x10-6)( 41306.33) = 0.07 m3/s

SD5 = Q17 = (0.825)( 2.04x10-6)( 29920.64) = 0.05 m3/s

SD6 = Q17 = (0.825)( 2.04x10-6)( 121962.72) = 0.21 m3/s

SD7 = Q19 = (0.825)( 2.04x10-6)( 273721.21) = 0.46 m3/s

SD8 = Q20 = (0.825)( 2.04x10-6)( 9060) = 0.02 m3/s

SD9 = Q21 = (0.825)( 2.04x10-6)( 11165) = 0.02 m3/s

SD10 = Q22 = (0.825)( 2.04x10-6)( 5700) = 0.01 m3/s

SD11 = Q23 = (0.825)( 2.04x10-6)( 11270.57) = 0.02 m3/s

SD12 = Q24 = (0.825)( 2.04x10-6)( 25500) = 0.04 m3/s

SD13 = Q25 = (0.825)( 2.04x10-6)( 128336.98) = 0.22 m3/s

SD14 = Q26 = (0.825)( 2.04x10-6)( 128071.93) = 0.22 m3/s

SD15 = Q27 = (0.825)( 2.04x10-6)( 54031.28) = 0.09 m3/s

SD16 = Q28 = (0.825)( 2.04x10-6)( 140800) = 0.24 m3/s

SD17 = Q29 = (0.825)( 2.04x10-6)( 86543.91) = 0.15 m3/s

SD18 = Q30 = (0.825)( 2.04x10-6)( 273721.21) = 0.46 m3/s

32
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Manning’s Flow Rate Formula

2 1
𝑘
Q = 𝑛 𝑅3 𝑆 2 A

Where:

Q = Flow Rate

A = Cross Sectional Area of the Drainage Canal

R = Hydraulic Radius of the Flow Cross-section

S = Slope of the Drainage Canal = 0.0004

k = Unit Conversion Factor = 1.00 for Metric Units

n = Manning Coefficient, 0.014 for Concrete, Timber Forms

𝐴 𝐷
R= =
𝑃 4

Where:

R = Hydraulic Radius of the Flow Cross-section

A = Cross Sectional Area of Drainage Canal

P = Wetted Perimeter

D = Diameter of Canal

Therefore:

8 1
π(𝐷)3 (𝑆)2
Q= 5
𝑛4 3

33
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Table 12: Cross Sectional Area and Diameter of Drainage System in Laoag City.

Flow Rate Cross Sectional Area (m2) Diameter

Q1 3.00 1.95

Q2 3.00 1.95

Q3 3.00 1.95

Q4 3.00 1.95

Q5 3.00 1.95

Q6 3.00 1.95

Q7 3.00 1.95

Q8 3.00 1.95

Q9 3.00 1.95

Q10 3.00 1.95

Q11 3.00 1.95

Q12 3.00 1.95

Q13 1.50 1.38

Q14 1.50 1.38

Q15 1.50 1.38

Source: Field Survey

34
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Flow Rate Cross Sectional Area (m2) Diameter

Q16 1.50 1.38

Q17 1.50 1.38

Q18 1.50 1.38

Q19 1.50 1.38

Q20 1.50 1.38

Q21 1.50 1.38

Q22 1.50 1.38

Q23 1.50 1.38

Q24 1.50 1.38

Q25 1.50 1.38

Q26 1.50 1.38

Q27 1.50 1.38

Q28 1.50 1.38

Q29 1.50 1.38

Q30 1.50 1.38

Source: Field Survey

35
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Average Velocity of Water

8 1 8 1
π(1.95)3 (0.0004)2 π(1.95)3 (0.0004)2
Q1 = 5 = 2.64m/s Q9 = 5 = 2.64m/s
(0.014)(4)3 (0.014)(4)3

8 1 8 1
π(1.95)3 (0.0004)2 π(1.95)3 (0.0004)2
Q2 = 5 = 2.64m/s Q10 = 5 = 2.64m/s
(0.014)(4)3 (0.014)(4)3

8 1 8 1
π(1.95)3 (0.0004)2 π(1.95)3 (0.0004)2
Q3 = 5 = 2.64m/s Q11 = 5 = 2.64m/s
(0.014)(4)3 (0.014)(4)3

8 1 8 1
π(1.95)3 (0.0004)2 π(1.95)3 (0.0004)2
Q4 = 5 = 2.64m/s Q12 = 5 = 2.64m/s
(0.014)(4)3 (0.014)(4)3

8 1 8 1
π(1.95)3 (0.0004)2 π(1.38)3 (0.0004)2
Q5 = 5 = 2.64m/s Q13 = 5 = 1.05m/s
(0.014)(4)3 (0.014)(4)3

8 1 8 1
π(1.95)3 (0.0004)2 π(1.38)3 (0.0004)2
Q6 = 5 = 2.64m/s Q14 = 5 = 1.05m/s
(0.014)(4)3 (0.014)(4)3

8 1 8 1
π(1.95)3 (0.0004)2 π(1.38)3 (0.0004)2
Q7 = 5 = 2.64m/s Q15 = 5 = 1.05m/s
(0.014)(4)3 (0.014)(4)3

8 1
π(1.95)3 (0.0004)2
Q8 = 5 = 2.64m/s
(0.014)(4)3

36
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

8 1 8 1
π(1.38)3 (0.0004)2 π(1.38)3 (0.0004)2
Q16 = 5 = 1.05m/s Q24 = 5 = 1.05m/s
(0.014)(4)3 (0.014)(4)3

8 1 8 1
π(1.38)3 (0.0004)2 π(1.38)3 (0.0004)2
Q17 = 5 = 1.05m/s Q25 = 5 = 1.05m/s
(0.014)(4)3 (0.014)(4)3

8 1 8 1
π(1.38)3 (0.0004)2 π(1.38)3 (0.0004)2
Q18 = 5 = 1.05m/s Q26 = 5 = 1.05m/s
(0.014)(4)3 (0.014)(4)3

8 1 8 1
π(1.38)3 (0.0004)2 π(1.38)3 (0.0004)2
Q19 = 5 = 1.05m/s Q27 = 5 = 1.05m/s
(0.014)(4)3 (0.014)(4)3

8 1 8 1
π(1.38)3 (0.0004)2 π(1.38)3 (0.0004)2
Q20 = 5 = 1.05m/s Q28 = 5 = 1.05m/s
(0.014)(4)3 (0.014)(4)3

8 1 8 1
π(1.38)3 (0.0004)2 π(1.38)3 (0.0004)2
Q21 = 5 = 1.05m/s Q29 = 5 = 1.05m/s
(0.014)(4)3 (0.014)(4)3

8 1 8 1
π(1.38)3 (0.0004)2 π(1.38)3 (0.0004)2
Q22 = 5 = 1.05m/s Q30 = 5 = 1.05m/s
(0.014)(4)3 (0.014)(4)3

8 1
π(1.38)3 (0.0004)2
Q23 = 5 = 1.05m/s
(0.014)(4)3

37
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Table 13: Tabulation of Result for the Drainage Assessment in Laoag City.

Street Rational Method Manning’s Conclusion

Formula

Q1 0.02 2.64 OK

Q2 0.09 2.64 OK

Q3 0.10 2.64 OK

Q4 0.06 2.64 OK

Q5 0.03 2.64 OK

Q6 0.02 2.64 OK

Q7 0.02 2.64 OK

Q8 0.02 2.64 OK

Q9 0.07 2.64 OK

Q10 0.15 2.64 OK

Q11 0.04 2.64 OK

Q12 0.01 2.64 OK

Q13 0.13 2.64 OK

Q14 0.33 1.05 OK

Q15 0.21 1.05 OK

38
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Street Rational Method Manning’s Conclusion

Formula

Q16 0.07 1.05 OK

Q17 0.05 1.05 OK

Q18 0.21 1.05 OK

Q19 0.46 1.05 OK

Q20 0.02 1.05 OK

Q21 0.02 1.05 OK

Q22 0.01 1.05 OK

Q23 0.02 1.05 OK

Q24 0.04 1.05 OK

Q25 0.22 1.05 OK

Q26 0.22 1.05 OK

Q27 0.09 1.05 OK

Q28 0.24 1.05 OK

Q29 0.15 1.05 OK

Q30 0.46 1.05 OK

39
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

A Proposed Drainage Canal is designed for future purposes.

Figure 7: Proposed Drainage Canal

Source: The Researcher

40
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Figure 8: Proposed Drainage Canal Layout.

Source: Self-Made Map by The Researcher

41
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

CHAPTER V

CONCLUSION AND RECOMMENDATIONS

Conclusion

The Drainage and Flood Risk Assessment on Flooded Barangays are considered to

be an effective method in reducing serious damages that floods caused to provide

information and general guides to land planning.

The researcher found out that there was a slight difference between the flood

hazard map in the city planning and the actual floods happening in Laoag City. Some areas

were flooded due to the elevation of their houses were lower than the level of the road.

Regardless of the differences, the current flood hazard map was still a reliable source in

managing flood. The flood hazard map can assist in managing flood as a source for

expected water depth/levels of an area flooded.

In the assessment of drainage, the results indicate that some conduits in the urban

drainage network were in bad condition and should be maintained properly, while the

others represent an acceptable performance in conveying the urban runoff and did a nice

job in preventing urban flooding in the region.

Most of the barangays on urban areas, have low susceptibility of flood, while some

of the barangays near the river have high susceptibility of flood.

42
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Recommendations

Maintenance of the drainage system is a way to avoid problems involving to flood.

There are many ways in to maintain the drainage system in Laoag City. These are some

recommendations in maintaining the drainage system:

1. Conduct inspection frequently during dry seasons and mostly during rainy seasons

in areas that has problem where sediments which clog the passageway by means of

sedimentation, drainage system should be cleaned and repaired if needed.

2. Residents of every barangay should have discipline in throwing of garbage.

3. Drainage canals should have signs such us “No throwing of garbage here.”. If

violated, a penalty or fine will be imposed to the violators.

4. Every barangay should have community service weekly to maintain cleanliness of

the areas of drainages.

5. The barangay officials should encourage the barangay people to participate in local

drills.

43
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

APPENDIX A

44
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

45
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

APPENDIX B

46
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Dear Sir/Ma’am
I am Khryzen Doloroso, a 5th year Civil Engineering student at Divine Word
College of Laoag. I am currently conducting a thesis entitled “Drainage and Flood Risk
Assessment on Flooded Barangays in Laoag City”. Your responses will greatly contribute
to this research.
Thank you for your kind cooperation. God bless.
________________________________________________________________________

Direction: Please provide the following information by filling in the space provided:
Name (Optional): _____________________________ Date: ____________
Address: ____________________________________ Age: _____

1. How long have you been living here?

_______________________________________________________________

2. If your house is flooded, where do you stay? If in an evacuation center, please

specify where it is.
_______________________________________________________________

3. How many times did you experience flood while living at this address?
___ Never ___ 1-5 times
___ 1-20 times ___ Many times

4. What sources of flooding are you most concerned about?

___ River ___Canal
___ Creek ___Heavy rain pours
___Irrigation others: _______________

5. What is the distance of your property to any potential source of flood?

____ Far
____ Near

47
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

6. Just before flooding occurs, how did you first become aware that flooding might
reach your home?
____TV ____Telephone by others
____Radio ____Face to face by public workers
____Newspaper ____Face to face by others
____Siren ____Observing the water levels
____Telephone by public workers others ___________________
7. Please check the necessary information
Area of Concern YES NO
Are you aware of the flood hazard map?
Are you aware of the disaster warning system in Laoag City?
Are you aware that your building is at risk of flooding?
Are you participating in the local drills?
Do you think your community has the necessary information and
resources to be ready if flooding occurs?
Are you prepared to deal with the flooding events?
Do you believe that the involvement of your community in responding
to flooding with the assistance of other public services is important?

8. What was the maximum water level and duration of flood that entered your
building?
Year Depth Duration

9. What measure was taken to prevent the building from flood?

____Pumped
____Used any type of temporary barriers
____Did nothing
Other ways __________________________________________________

48
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

10. Government Response Before, During and After Flooding Events.

Please check the necessary information
3 – Very Responsive 2 – Responsive 1 – Not Responsive

Area of Concern 1 2 3

Evacuation Procedure
Early Warning System
Provision of Temporary Shelter
Provision of Necessities
Relief Operation
Search and Rescue

11. Are there any other comments you would like to make in relation to flooding
matters?
__________________________________________________________________

________________________________________________________________________

________________________________________________________________________

________________________________________________________________________

________________________________________________________________________

Thank you for taking the time to complete this questionnaire.

49
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

APPENDIX C

50
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

FLOODED AREAS

Barangay 7-B, Laoag City

Barangay 11, Laoag City

Source: Resident from Laoag City

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

APPENDIX D

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

RESPONDENTS ANSWERING THE QUESTIONNAIRE

Barangay 1, Laoag City

Barangay 14, Laoag City

Source: The Researcher

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Barangay 11, Laoag City

Barangay 5, Laoag City

Source: The Researcher

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

APPENDIX E

55
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

SEARCH AND RESCUE OPERATION LED BY THE MAYOR OF LAOAG CITY

HON. MICHAEL MARCOS KEON

Barangay 7-B, Laoag City

Source: City of Laoag Facebook Page

56
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Barangay 7-B, Laoag City

Source: City of Laoag Facebook Page

57
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

APPENDIX F

58
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

MAPS OF LAOAG CITY

Proposed Land Use Map Source: City of Laoag

Urban Base Map Source: City of Laoag

59
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Land Use Map Urban Source: City of Laoag

Surface & Ground Water Source: City of Laoag

60
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Flood Hazard Map Source: City of Laoag

61
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Evacuation Map (Urban) Source: City of Laoag

62
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Evacuation Map (Rural) Source: City of Laoag

63
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

APPENDIX G

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

CANALS IN LAOAG CITY THAT NEEDS MAINTENANCE

Barangay 11, Laoag City

Barangay 10, Laoag City

65
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Barangay 9, Laoag City

Source: The Researcher

66
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

CURRICULUM

VITAE

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 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

DOLOROSO, KHRYZEN
#60 Brgy. 15, Laoag City, Ilocos Norte
Mobile No.: 0961 331 5651
E-mail Address: dkhryzen@yahoo.com

PERSONAL PARTICULARS:
Date of Birth : May 24, 1999
Citizenship : Filipino
Sex : Male
Civil Status : Single
Height : 5’3"
Weight : 47 kgs
Religion : Born Again Christian

HIGHEST EDUCATIONAL BACKGROUND

Tertiary Divine Word College of Laoag

Barangay 13, General Segundo Avenue, Laoag City, Ilocos Norte
Bachelor of Science in Civil Engineering
2015 – Present (undergraduate)

Secondary Ilocos Norte College of Arts and Trade

Barangay 5 P. Gomez St., Laoag City
2011 – 2015

Intermediate Northern Christian College

Barangay 5 A. Samonte St., Laoag City
2006 – 2011

68
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

BIBLIOGRAPHY

Websites

Chapter II Review of Literature and Related Studies, Retrieved from:

https://www.academia.edu/34731619/CHAPTER_II_REVIEW_OF_LITERATU
RE_AND_RELATED_STUDIES

Rainfall and Rain days, Retrieved from:

https://www.weather-and-climate.com/laoag-weather/laoag/ph.aspx

Drainage System, Retrieved from:

https://www.quora.com/What-is-a-drainage-system

Flood Mitigation, Retrieved from:

https://dnr.nebraska.gov/floodplain/flood-mitigation

Rational Method for Flow Rate, Retrieved from:

https://www.brighthubengineering.com/hydraulics-civil-engineering/60842-the-
rational-method-for-calculation-of-peak-storm-water-runoff-rate/

Manning’s Formula for Rectangular Open Channel, Retrieved from:

https://www.lmnoeng.com/water.php

Pornasdoro, et.al, (2014). Flood Risk of Metro Manila Barangays: A GIS Based Risk

Assessment Using Multi-Criteria Techniques Retrieve from:

https://conference.surp.upd.edu.ph/downloads/JURP1/JURP_04_PORNASDORO
_arial_lines_05a.pdf

Sagala S.A.H. (2006). Analysis of Flood Physical Vulnerability in Residential Areas.

Retrieved from:

https://webapps.itc.utwente.nl/librarywww/papers_2006/msc/upla/sagala.pdf

69
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Porcil, J.T. (2009), The Philippine Disaster Management System, Retrieved from:

https://www.adrc.asia/aboutus/vrdata/countryreport/josefina2009_cr.pdf

Geminiano, G. (2013). Worst Floods and Typhoons in the Philippines, Retrieved from:

https://hubpages.com/education/Worse-Floods-in-the-Philippines

Ancheta, et.al, (2017) Flood Risk Reduction and Management, Retrieved from:

https://www.researchgate.net/publication/324137132_Flood_Risk_Reduction_and
_Management

Chang H.K., et.al, (2013). Improvement of a drainage system for flood management with

assessment of the potential effects of climate change, Retrieved from:

https://doi.org/10.1080/02626667.2013.836276

Robas, R.J., (2014) Flood Disaster Risk Reduction and Risk Management of Pasig City,

Retrieved from:

https://www.researchgate.net/publication/269166941_FLOOD_DISASTER_RIS
K_REDUCTION_AND_RISK_MANAGEMENT_OF_PASIG_CITY

Twumasiwaah, K.A., (2016) Urban Flood Risk Management: A Case Study of Aboabo,

Kumasi. Retrieved from:

http://ir.knust.edu.gh/bitstream/123456789/10343/1/THESIS-WORD.pdf

Saru, (2012) A Study on Causes of Flood, Retrieved from:

http://umpir.ump.edu.my/id/eprint/7901/1/AINATUL_SHAHIRAH_BINTI_MO
HD_SARU.PDF

70
 DIVINE WORD COLLEGE OF LAOAG
School of Engineering and Architecture
Society of Engineering and Architecture Students
General Segundo Avenue Laoag City, 2900 Philippines
Tel No.: (077) 772-1228, 772-0736, 773-2082, 771-6380 Local 222

Rational Method for Flow Rate, Retrieved from:

https://www.brighthubengineering.com/hydraulics-civil-engineering/60842-the-
rational-method-for-calculation-of-peak-storm-water-runoff-rate/

Manning’s Formula for Rectangular Open Channel, Retrieved from:

https://www.lmnoeng.com/water.php

Pornasdoro, et.al, (2014). Flood Risk of Metro Manila Barangays: A GIS Based Risk

Assessment Using Multi-Criteria Techniques Retrieved from:

https://conference.surp.upd.edu.ph/downloads/JURP1/JURP_04_PORNASDORO
_arial_lines_05a.pdf

Sagala S.A.H. (2006). Analysis of Flood Physical Vulnerability in Residential Areas.

Retrieved from:

https://webapps.itc.utwente.nl/librarywww/papers_2006/msc/upla/sagala.pdf

Porcil, J.T. (2009), The Philippine Disaster Management System, Retrieved from:

https://www.adrc.asia/aboutus/vrdata/countryreport/josefina2009_cr.pdf

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