EIGHTEENTH CONGRESS OF THE 
REPUBLIC OF THE PHILIPPINES 
First Regular Session
)
S E N A T E
S. No. 579
f ' l i . '  1 lil
jf I!)C feivrrtmp
*19 
JUL 17 
P5 -48
Introduced by Senator Grace Poe
Rbv-i-
AN ACT
PROVIDING 
FOR THE 
MANAGEMENT, 
CONTROL, 
REGULATION, AND 
UTILIZATION 
OF 
RAINWATER 
RUNOFF, 
AND 
IMPROVEMENT 
OF 
ECOLOGICAL 
CHARACTERISTICS 
OF 
CATCHMENTS 
TO 
ADDRESS 
FLOODING AND WATER SUPPLY NEEDS IN  URBAN AND RURAL CENTERS, 
AND 
CREATING 
THE 
NECESSARY 
INSTITUTIONAL 
MECHANISMS 
THEREFOR
EXPLANATORY NOTE
The Philippines has witnessed an increasing frequency and intensity of rain 
which causes severe flooding and results to unquantifiable economic losses. 
Although this has been primarily attributed to climate change, data shows that these 
woes are the result of poorly planned development with no provisions for control 
and regulation of runoff flows. Land use conversion, deforestation, coupled with the 
lack of retention/detention system are among the reasons why flooding occurs.
On the other side of the scale is the issue of the security of water supply for 
the growing urban and rural centers. The problem on one side could be the solution 
for the other if the necessary management, control, and regulation of such runoff 
volume of water is established. Thus, the solution being forwarded is to capture and 
store rainwater and utilize it for irrigation, groundwater recharge, firefighting, and 
other water supply purposes. Through this, water is conserved and runoff is 
reduced.
The quantity and quality of runoff water is directly correlated with the quality 
and size of our catchment. 
Hence, emphasis on the protection, planning, 
management of catchment is at the core of the program. This will require the
1


participation of the agencies such as the Department of Environment and Natural 
Resources (DENR), Department of Agriculture (DA), Department of Public Works and 
Highways (DPWH), and the respective local government units.
Thus, the immediate approval of this bill is eagerly sought.
^
 / f  GK.\CE POK . _  .
/


EIGHTEENTH CONGRESS OF THE 
REPUBLIC OF THE PHILIPPINES 
First Regular Session
)
S E N A T E
S. No. u79
- ol ll)i £ip*'utnrp
:v'
ss'raa:.
•19 
JUL 17 P5 -M
Introduced by Senator Grace Poe rec;
S
- i
AN ACT
PROVIDING 
FOR THE 
MANAGEMENT, CONTROL, REGULATION, AND 
UTILIZATION 
OF 
RAINWATER 
RUNOFF, 
AND 
IMPROVEMENT 
OF 
ECOLOGICAL CHARACTERISTICS OF CATCHMENTS TO ADDRESS FLOODING 
AND WATER SUPPLY NEEDS IN URBAN AND RURAL CENTERS, AND 
CREATING THE NECESSARY INSTITUTIONAL MECHANISMS THEREFOR
Be it enacted by the Senate and the House o f Representatives o f the Republic o f the 
Philippines in Congress assembled:
1 
Section 1. Purpose. -  The purpose of this Act is to establish minimum rainwater
2 
management requirements and controls to protect and safeguard the general health,
3 
safety, and welfare of the public. This seeks to meet that purpose through the
4 
following objectives:
5 
a. Minimize increase in rainwater runoff from any development, both existing and
6 
proposed, in order to reduce flooding, 
siltation, increases in 
stream
7 
temperature, and stream bank erosion and maintain the integrity of stream
8 
channels;
9 
b. Minimize increase in non-point source pollution caused by rainwater runoff
10 
development which would otherwise degrade local water quality;
11 
c. Minimize the annual volume of surface water runoff which flows from any
12 
specific site during and following development to not exceed the pre-
13 
development hydrologic regime to the maximum extent practicable; and
14 
d. Reduce rainwater runoff rates and volumes, soil erosion, and non-point source
15 
pollution, wherever possible, through rainwater management controls and to
16 
ensure that these management controls are properly maintained and pose no
17 
threat to public safety.


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Sec. 2. Definition o f Terms. -  As used in this Act:
2 
a) Applicant- means a property owner or agent who has filed an application for a
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rainwater management permit.
4 
b) Building - any structure built for the support, shelter, or enclosure or person,
5 
animals, chattels, or moveable property of any kind and which is permanently
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affixed to the land.
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c) Building OfTicial- Local Building Official as appointed or designated pursuant to
8 
PD 1096.
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d) Certificate o f Occupancy - a permit issued by the Zoning Officer indicating that
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the use of the building or land in question is in conformity with the Zoning
11 
Ordinance or that there has been a legal variance there from, as provided by
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ordinance.
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e) Channel- means a natural or artificial watercourse with definite bed and banks
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that conducts continuously or periodically flowing water.
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f) Dedication - means the deliberate appropriation of property by its owner for
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general public use.
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g) Detention - means the temporary storage of rainwater runoff in a rainwater
18 
management practices with goals of controlling peak discharge rates and
19 
providing gravity settling of pollutants.
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h) Developer - means a person or entity who undertakes land disturbance or
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development activities.
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i) Development - means any man-made change to improve or unimprove real
23 
estate, including but not limited to buildings or other structures, mining,
24 
dredging, filling, grading, paving, excavation, or drilling operation.
25 
j) Drainage Easement- means a legal right granted by the landowner to a grantee
26 
allowing use of private land for rainwater management purposes.
27 
k) Erosion and Sediment Control Plan - means a plan that is designed to minimize
28 
the accelerated erosion and sediment runoff 
at a site during construction
29 
activities.
30 
I) Hotspot- is an area where land use or activities generate highly contaminated
31 
runoff, with concentrations of pollutants 
in excess of those typically 
found in
32 
rainwater.


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m) Impervious Coverage - refer to those surfaces that cannot effectively infiltrate
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rainfall (e.g., building rooftops, pavement, sidewalks, driveways, etc.)
3 
n) Industrial Rainwater Permit - refers to a National Pollutant Discharge
4 
Elimination System permit issued to a commercial industry or group of
5 
industries which regulates the pollutant levels associated with industrial
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rainwater discharges or specifies on-site pollution control strategies.
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o) Infiltration - is the process of percolating rainwater into the subsoil.
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p) Infiltration Facility- is any structure or device designed to infiltrate water to the
9 
subsurface. These facilities may be above grade or below grade.
10 
q) Land Disturbance Activity - is any activity which changes the volume or peak
11 
flow discharge rate of rainfall from the land surface. This may include grading,
12 
digging, cutting, scraping, or excavating of soil, placement of fill materials,
13 
paving, construction, substantial removal of vegetation, or any activity which
14 
bares soil or rock or involves the diversion or piping of any natural or man-
15 
made watercourse.
16 
r) Landowner - means the legal or beneficial owner of land, including those
17 
holding the right to purchase or lease the land, or any other person holding
18 
proprietary rights in the land.
19 
s) Off-Site Facility- means a rainwater management measure located outside the
20 
subject property boundary 
described in the permit application for land
21 
development activity.
22 
t) On-Site Facility - means a rainwater management measure located within the
23 
subject property boundary 
described in the permit application for land
24 
development activity.
25 
u) /?ec/?ar57e-means the replenishment of underground water reserves.
26 
v) Redevelopment- means any construction, alteration or improvement exceeding
27 
100 square meters in areas where existing land use is high density commercial,
28 
industrial, institutional or multi-family residential.
29 
w) Stop Work Order - means an order issued which requires that all construction
30 
activity on a site be stopped.


1 
x) Rainwater Design Manuai - means the Planning and Design Manual for the
2 
Control of Erosion, Sediment and Rainwater written by Department of Public
3 
Works and Highways.
4 
y) Rainwater Management - means the use of structural or non-structural
5 
practices that are design to reduce rainwater runoff pollutant loads, discharge
6 
volumes, and/or peak flow discharge rates.
7 
z) Rainwater Retrofit - means a rainwater management practice designed for an
8 
existing development site that previously had either no rainwater management
9 
practice in place or a practice inadequate to meet the rainwater management
10 
requirements of the site.
11 
a^) Rainwater Runoff - means water flow on the surface of the ground, resulting
12 
from precipitation.
13 
bb)Rainwater Treatment Practices - mean measures, either structural or
14 
nonstructural, that are determined to be the most effective, practical means for
15 
preventing or reducing point source or nonpoint source pollution inputs to
16 
rainwater runoff and water bodies.
17 
cc) Watercourse - means a permanent or intermittent stream or other body of
18 
water, either natural or man-made, which gathers or carries surface.
19 
Sec. 3. Requirements for Rainwater Management Rian. -  All landowners or
20 
developers of proposed commercial, industrial and residential development or any
21 
residential multi-dwelling units of more than 1,000 sqm land area must submit
22 
Rainwater Management Plan (RMP) as part of the site development application and
23 
approval process.
24 
The RMP shall include the following information:
25 
a. Description of Existing Conditions - Description of the existing condition shall
26 
be shown on a map. It shall include:
27 
1. Topographic map with 1.0 meter minimum contours line or an
28 
appropriate contour interval) of the land proposed for development or
29 
redevelopment.
30 
2. Location natural waterways including banks and centerline of streams
31 
and channels.


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3. The normal shoreline, coastlines, outline of lakes, natural depressions 
and ponds, including drainage flow lines.
Quantification of flows (discharge and volume) in its natural condition shall be 
provided; and
b. Proposed Site Development Plan - The proponent shall provide Site 
Development Plan (SDP) in an appropriate scale and size showing the following:
i. 
Retention/detention basins and lines of inflow and outflow;
ii. 
The location, size and slope of rainwater conduits and drainage swales;
iii. 
Rain, sanitary and combined sewer and outfalls; and,
iv. 
Delineation of upstream and downstream drainage features and 
watersheds which might be affected by the development; and other 
environmental features including limits of wetlands areas, green buffers, 
planting strips, and any designated natural areas for rainwater 
management.
c. Description of Proposed Rainwater Management System (RMS) - The proposed 
RMS shall be designed to safely and completely managed rainwater runoff 
onsite or offsite and provide facility to regulate the increased rainwater runoff, 
thus, maintain the natural hydrologic cycle and condition of flow in a locality. 
The purpose of the RMS is to reduce the risk of downstream flooding by 
reducing the amount of runoff and regulating the discharge release at a given 
time.
The proposed RMS shall be accompanied by hydrologic and hydraulic 
calculations to adequately demonstrate the effectiveness of the plan.
The proposed RMS shall be designed to meet the desired flood frequency 
which is designated to a particular drainage structure as stated in the Design 
Manual of the DPWH. Higher flood frequency such as 25-year or higher may be 
required for major rivers and waterways. Specific details of the design criteria 
are incorporated in Section 4.
The plan shall be accompanied by relevant data (such as rainfall data in a locality), 
maps and other descriptive material to include the following.
1) The extent of catchment, drainage channels on site and direction of the flow of 
the channels including the final outfall of the discharge from the site;


1 
2) Hydrologic and hydraulic design calculations for the pre-development and post
2 
development conditions for the design storm proposed in Section 5. The
3 
calculations for determining peak flows are found in the Rainwater Design
4 
Manual to include description of design storm frequency, intensity, and
5 
duration, time of concentration, soil curve number or runoff coefficients, peak
6 
runoff rates and total runoff volumes, infiltration rates, culvert capacities, flow
7 
velocities, data on the increase in rate and volume of runoff for the design
8 
storm; and,
9 
3) Technical specifications of the Proposed SMS, providing descriptions of
10 
proposed rainwater conveyance practices to be on-site, existing off-site
11 
rainwater conveyance system including receiving streams, channels, and outfall
12 
and inlet locations. Include elevations of locations and high water elevations.
13 
Sec. 4. Utilization o f Rainwater. -  The following are the specific utilization of
14 
rainwater and the recommended facility to harness its volume for the intended use:
15 
a) Rainwater for Rural Irrigation - Agriculture in the Philippines is predominantly
16 
rainfed. Rainwater catchments thus hold a significant potential for improvement
17 
of rainwater use efficiency and sustainment of rainfed and upland agriculture
18 
in the country.
19 
b) Rainwater for Urban Irrigation - Most of the urban centers are currently
20 
dependent on Class A water quality for irrigation supply which are costly and
21 
environmentally unsustainable. Utilization of Class A water for yard irrigation
22 
shall be minimized if not prohibited. Instead, rainwater shall be utilized for such
23 
purposes. The irrigation water shall come from the rainwater detention system.
24 
Rainwater as source for urban irrigation and/or watering of lawns shall
25 
be indicated in the development plans. Secondary source of water for irrigation
26 
may also come from treated grey water from effluent of treatment facility.
27 
c) Rainwater for Groundwater Recharge - The RMS is intended mainly to ensure
28 
natural balance of the hydrologic cycle by allowing rainwater to recharge the
29 
groundwater table that sustains the yield and production of deep wells. The
30 
proposed facility to allow for recharge may be in the form of the following best
31 
management system:


1 
1) Lagoon or retention pond that allows for natural seepage to the ground
2 
water aquifer.
3 
2) Swales and depression storage
4 
3) Porous or pavers blocks on some developed areas
5 
4) Retention channels, etc.
6 
The sizes and dimensions of the above facility is dependent on the rainfall
7 
intensity and the size of the development.
8 
d) Rainwater for Firefighting - Considerable amount of water is also needed for
9 
firefighting. At present, water for firefighting comes from potable water sources
10 
which are expensive. Rainwater is a good substitute. The quality requirement
11 
may be upgraded to meet required standard that may not cause health issues
-12 
and abrasion to machines. A separate storage tank for fire water reserve shall
13 
be constructed. Upgrading of the quality of water may be done using simple
14 
filtration system to remove suspended solids and other coarse materials that
15 
will interfere with electromechanical and pipe systems. Other laws concerning
16 
the requirement of water for firefighting shall be considered.
17 
e) Rainwater for Non-Potable Water Supply Source - Rainwater subjected to
18 
primary and secondary treatment can be a viable secondary source for water
19 
supply in urban and rural areas. It can be used for the following purposes:
20 
1) Watering plants;
21 
2) Washing of cars, floor yards;
22 
3) Flushing of toilet (water quality should meet certain standard to avoid
23 
discoloration of fixtures); and
24 
4) Fish ponds, etc.
25 
It is necessary to provide separate guidelines for water quality on the above
26 
mentioned usage for various commercial and industrial purposes. For potable
27 
water supply, strict compliance of water quality that will meet the Philippine
28 
National Standard for Drinking Water (PNSDW) is required.
29 
f) Rainwater for Ecological Requirements - Seasonal fluctuation of rainfall affects
30 
the Rain flora and fauna of waterways. The management of rainwater runoff
31 
provides steady release of water to the waterways enhancing their continued
32 
supply


1 
Sec. 5. Preparation o f the Rainwater Design Manuai. -  The Department of
2 
Public Works and Highways (DPWH) is hereby directed to prepare the Rainwater
3 
Design Manual which should incorporate the following criteria:
4 
a) All sites shall establish rainwater management system to control the peak flow
5 
rates of rainwater discharge associated with specified design storms and reduce
6 
the generation of rainwater for the site to provide treatment for both water
7 
quality and quantity. Peak post-construction rainwater runoff will not exceed
8 
peak pre construction rainwater runoff from the site to the greatest extent
9 
possible.
10 
b) All rainwater runoff generated from any development shall not discharge
11 
untreated rainwater directly into a jurisdictional wetland or local water body
12 
without adequate treatment.
13 
c) Structural and non-structural Rainwater Treatment System (RTS) shall be
14 
designed to treat the first 20 mm of rainwater runoff. That means for every one
15 
(1) hectare of new development, a 200 cubic meters of detention /retention
16 
tank shall be constructed to minimize flooding and improve water quality.
17 
Sanitary wastewater treatment facilities shall be designed and installed to
18 
comply with existing health regulations and meet the Effluent Standard of the
19 
DENR.
20 
d) Untreated sanitary waste should not be discharge to waterways and land
21 
surface without proper treatment and shall not come in contact with rainwater
22 
runoff. For discharge of treated effluent to water bodies, it shall meet the river
23 
classification. For unclassified rivers and water courses. Class C water shall be
24 
met. For discharge to urban drainage system, the minimum requirement shall
25 
be Class D effluent. Any variation with the required standard set by DENR, the
26 
prescription provided by the DENR shall be followed.
27 
e) To protect stream channels from degradation, velocity of runoff water shall be
28 
limited to less than 1.0 m/s otherwise bank protection shall be provided.
29 
f) Rainwater discharges to critical areas with sensitive resources (including
30 
shellfish beds, swimming areas, water supply reservoirs and groundwater
31 
recharge areas) may be subject to additional performance criteria, or may need
32 
to utilize or restrict certain rainwater management practices.


1 
g) Rainwater discharges from land uses or activities with higher potential pollutant
2 
loadings, known as "hotspots," may require the use of specific structural and
3 
pollution prevention practices.
4 
h) Prior to design, applicants are required to consult with the Building Official to
5 
determine if they are subject to additional rainwater design requirements.
6 
i) For existing development or develop areas, the rainwater management system
7 
requirement may be imposed on the following conditions:
8 
1) Existing or old development shall submit to the Building officials plans of
9 
existing rainwater management system to demonstrate its contribution
10 
to flood control and mitigation and rainwater management program;
11 
2) That at least 50% of the required volume shall be met within five (5)
12 
years from the effectivity of this Act; and
13 
3) The total required volume of storage may be the cumulative volume
14 
store from various storage such as cistern, lagoon onsite or offsite, and
15 
depression storage
16 
Sec. 6. Construction Inspection. -
17 
a) The applicant must notify the Building Official in advance before the
18 
commencement of construction.
19 
b) All applicants for commercial and multi-family residential units over four (4)
20 
units are required to submit actual record drawings for any rainwater
21 
management practices located on-site after final construction is completed.
22 
The Plan must show the final design specification for all rainwater
23 
management facilities and must be certified by a professional engineer. A final
24 
inspection is required before the release of any performance security,
25 
performance bond, or guaranty.
26 
c) 
Permanent vegetation must be seeded or planted within 30 days after the final
27 
grade is reached. Planting guidance for permanent vegetative practices is
28 
included in the Rainwater Design Manual. Any area of re-vegetation must
29 
exhibit a survival of a minimum of seventy-five percent (75%) of the crop
30 
cover throughout the year immediately following re-vegetation. Re-vegetation
31 
must be repeated in successive years until the minimum seventy-five (75%)
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survival for one (1) year is achieved.


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d) The City/Municipal Engineer shall inspect all drainage facilities while under 
construction. When facilities are not constructed according to approved plans, 
the local government unit (LGU) has the explicit authority to compel 
compliance and have any situations corrected which are not according to the 
approved plans. All drainage facilities located on private property, whether 
dedicated to the LGU or not, shall be accessible at all times for inspection by 
the City/Municipal engineer or other responsible public official.
e) The City/Municipal Engineer shall inspect all sanitary waste treatment facilities 
while under construction and upon completion to insure proper installation and 
connection to waste water collection systems when applicable. Proper function 
of sanitary waste treatment facilities is required prior final approval and 
issuance of a certificate of occupancy.
Sec. 7. Maintenance and Repair o f Rainwater Facilities. -
a) All rainwater management facilities must undergo a regular yearly inspection 
process at a frequency sufficient to determine the functioning ability of the 
conveyance system and any repair needs; at a minimum this should include 
inspection prior to the beginning of Typhoon Season, prior to any forecast 
major rains that may equal the design requirements and after any major rain 
events.
b) All drainage facilities located on private property, whether dedicated to the LGU 
or not, shall be accessible at all times for inspection by the City/Municipal 
Engineer or other responsible public officials. All sanitary waste treatment 
facilities located on private property shall be accessible for inspection for proper 
function by the City/Municipal Engineer or other responsible public officials 
where there is reason to suspect that a malfunction has resulted in rainwater 
runoff pollution by unsanitary waste.
c) Parties responsible for the operation and maintenance of a rainwater 
management facility shall make records of the installation and of all, 
maintenance and repairs, and shall retain these records for at least five years. 
These records shall be made available to the City during inspection of the facility 
and other reasonable times upon request.
10


1 
d) The Building Official will notify the owner in writing that maintenance is
2 
required. The owner will have 60 days from the receipt of such written notice
3 
to bring the facility into proper working order.
4 
Sec. 8. Enforcement and Penalties. -
5 
a) Any person found to be in violation of any of the terms and provisions of this
6 
Act shall be found guilty of a misdemeanor and subject to a fine not to exceed
7 
P50,000 or imprisoned for no more than ninety (90) days or both such fine and
8 
imprisonment. A continuance of a violation without reasonable effort on the
9 
part of the defendant to correct same shall be and constitute a new and
10 
separate offense each day.
11 
b) If the Building Official shall find that the provisions of this ordinance are
12 
violated, the person responsible for such violation shall be notified in writing,
13 
indicating the nature of the violation and ordering action necessary to correct
14 
it. Among those actions which he/she may be ordered is discontinuance of any
15 
actions on site.
16 
c) In case any post-construction rainwater practice is constructed, reconstructed,
17 
altered, repaired, or converted or any person would be damaged by such
18 
violation, in addition to other remedies, the Building Official may institute
19 
injunction, mandamus, or other appropriate action in proceeding to prevent
20 
violation of the final plan or any element of this plan.
21 
d) Violators may be required to restore land to its undisturbed condition. In the
22 
event that restoration is not undertaken within a reasonable time, after notice,
23 
the LGU may take necessary corrective action, the cost of which shall become
24 
a lien upon the property until paid.
25 
Sec. 9. Repeal. -  All laws, orders, rules, regulations, and issuances, or parts
26 
thereof, which are inconsistent with this law are hereby repealed or modified
27 
accordingly.
28 
Sec. 10. Effectivity. -  This Act shall take effect fifteen (15) days after its
29 
publication in the Official Gazette or in a newspaper of national circulation.
Approved,
11