JABATAN PENGAIRAN DAN SALIRAN(DEPARTMENT OF IRRIGATION AND DRAINAGE)

DRAINAGE PLAN SUMMARY SHEET

Local Authority : Majilis Daerah Tuaran

Proposed Development : Proposed subdivision and housing development on CL 045003496 at Kampung Torung Labuaya, Jalan Tanjong Lubuaya, District of Tuaran.

Location : Approximate 550 meter north of Tuaran Town and 400 meter north of Tuaran Police Station.

Development Plan Reference :

Drainage Plan Reference : A1

Project Proponent : M/S Empower Land Sdn Bhd

Professional Engineers :

DESIGN PARAMETERS / CRITERIA / ASSUMPTIONS

Catchment area (ha) : 0.922

Development site area (ha) : 0.922 (road and building)

Pre-development land conditions : An open area with less dense growth vegetation

Post-development land conditions : Proposed housing two and half and three storey terrace with low density, proposed level 6.2M A.S.M.L

Hydrology data: polynomial approximation IDF curve equation, east coast of Malaysia , Sabah

Design ARI: 5 years and 50 years

Hydrological and hydraulic analysis: MIDUSS V2

Parameter used:

Pre-development

Catchments Pervious ImperviousImpervious Flow

length (m)

Overland slope (%)

Manning ‘n’

Max. Infilt.

(mm/hr)

Min. Infilt.

(mm/hr)

Lag Cons. (hr)

Manning ‘n’

Max. Infilt.

(mm/hr)

Min. Infilt.

(mm/hr)

Lag Cons. (hr)

10 200 0.815 0.4 75 12.5 0.25 0.015 0 0 0.5

Post –development

Catchments Pervious ImperviousImpervious Flow

length (m)

Overland slope (%)

Manning ‘n’

Max. Infilt.

(mm/hr)

Min. Infilt.

(mm/hr)

Lag Cons. (hr)

Manning ‘n’

Max. Infilt.

(mm/hr)

Min. Infilt.

(mm/hr)

Lag Cons. (hr)

90 0.4 0.015

Storage detail:

Required detention drain volume =

Detention drain volume provided =

Actual detention drain volume on site =

DESIGN METHOD / SOFTWARES / REFERENCES

Urban stormwater management manual for Malaysia 2000 / MIDUSS V2

PROPOSED DRAINAGE / STORM WATER MANAGEMENT FACILITIES

For adjacent lands / properties affected

For storm water management of development site

Operation and maintenance

Compliance with statutory requirement (where relevant)

PROFESSIONAL ENGINEERS CERTIFICATION

I hereby certify that the proposed drainage/storm water facilities for this development are in accordance with the technical guidelines of Jabatan Pengairan dan Saliran Sabah and in compliance with all relevant statutory requirements, and that due to care has been taken in the design to ensure public safety and interest. I am fully responsible for the reliability and accuracy of all data and assumptions used, and the adequacy of the design for the entire drainage and storm water management facilities.

(Signed and stamped by Professional Engineer)

Date:

Proposed Subdivision and Housing Development on CL 045003496 at Kampung Torung Labuaya, Jalan Tanjong

Lubuaya, District of Tuaran

URBAN STORMWATER MANAGEMENT MANUAL FOR MALAYSIA 2000

Submitted by:

PERUNDING TECHNO-AWAM SDN BHDCIVIL, STRUCTURAL & GEOTECHNICALCONSULTING ENGINEERINGP.O. BOX 20443,88757, LUYANG, KOTA KINABALU,SABAH.TEL : 088-725019FAX : 088-724019

1. Introduction

This report is to present the estimation and method of controlling the runoff discharging into an existing drain at the north west top of the boundary development site after developing the two and half storey and three storey houses in CL 045003496 at Kampung Torung Lubuaya, District of Tuaran. The total area of development is about 0.922 ha. The control of the runoff of the developed area is by using On-Site Detention Storage Tank which controls the outfall is equal or less to the pre-development runoff.

1.1 Project Name

The title of this project is “PROPOSED SUBDIVISION AND HOUSING DEVELOPMENT ON CL 045003496 AT KG. TORUNG LABUAYA, JALAN TANJONG LUBUAYA, DISTRICT OF TUARAN”.

1.2 Project Description

This project comprises construction of building, water supply, drainage system, sewerage and road. The works include:

i. Piling workii. The construction of reinforced concrete structure

iii. The installation of water pipeline and sewer lineiv. The construction of sewerage treatment plant and drainage systemv. The construction internal road system

1.3 Project Location and Location Plan

The project site is located around 550 meter at north side of Tuaran Town, which pass after Bomba Station and Police Station. The location plan of this site is shown in Figure 1.

1.4 Project Proponent Detail

This project is implement by Empower Land Sdn Bhd.

The address of the developer is as follow:

No. 12-1, Jalan Kepong Usaha,Off Jalan Kepong, Kepong Business Center, 52100,Kuala Lumpur.

1.5 Civil and Structural Engineer

The Civil and Structural Engineer of this project is Perunding Jasa Sdn Bhd.

The address of the developer is as follow:

2nd Floor, Shoplot 22, Taman Victory,Mile 41/2, Jalan Penampang,88300 Kota Kinabalu, Sabah.Tel: 088-725019 Fax: 088-724019

1.6 Design Codes, Guidelines and Standard

The design codes , guidelines and standards are based on the Urban Stormwater Management Manual for Malaysia.

2. Existing Drainage System

2.1 Existing Landuse

The land is on an open area with little vegetation and dirt soil. Few housed are on the middle of the development site. There is an access to the site at the east side on development area.

2.2 Topography

The existing platform level of this area is about 4 meter to 5.3 meter. The profile of this area is high ground on the east side of the development area.

2.3 Pre-Development Catchment Discretisation

The pre-development runoff is discharge into the stream to the west side of the development site as heading to Sungai Tuaran.

2.4 Impacts of Proposed Development on the Existing System

The development will not affect the existing system as there is no major development as this area. Further the discharging point is near north west side of the development to Sungai Tuaran. It is evident that the proposed development will not have an impact to the existing system, as the discharge is controlled by on-site detention tank.

3. Proposed Drainage System

3.1 General

3.1.1 Proposed Landscape and Land Use

The proposed development is 16 units of two and half storey terrace houses, 4 units of three storey terrace house, 2 units three storey semi detached and 1 unit three storey detached. Open space of 923m2 will be provided.

3.1.2 Proposed Mitigation Measures

The mitigation measure is by providing on-site detention tank to control the discharge.

3.2 Design Calculation and Computer Modeling

The software uses for this analysis is MES: MiTS and MIDUSS version 2.

3.2.1 Design Parameter

Road side drain 5 years return period

Building perimeter drain 5 years return period

Manning ‘n’ 0.013 for concrete

0.035 for grass

Infiltration Method Horton Equation

Routing Method Linear Reservoir Method

3.2.2 Design Storm or Rainfall

The design rainfall is based on Kota Kinabalu rainfall station obtained from MIDUSS and MES. Intensity,duration and frequency curves are generated based on the Inanam rainfall station as shown in figure No.2

Base on the IDF Curve, the depth of the rain water for the return period of 5 years. 10 years and 100 years are tabulated in the following table no.1.

  ARIDuratio

n5

Years10

Years50

Years(Minutes

)Depth (mm)

5 23.13 25.42 28.4210 31.90 35.43 42.8315 38.97 43.50 54.4420 45.30 50.74 64.8425 51.15 57.42 74.4530 56.99 64.10 84.0535 62.03 69.78 92.3740 66.58 74.94 99.8745 70.73 79.69 106.7050 74.55 84.07 112.9655 78.08 88.13 118.7360 81.35 91.93 124.0865 84.41 95.49 129.06

70 87.28 98.83 133.7175 89.97 101.98 138.0780 92.51 104.96 142.1785 94.91 107.78 146.0490 97.18 110.47 149.7095 99.33 113.02 153.16100 101.38 115.45 156.45105 103.33 117.77 159.57110 105.19 119.99 162.55115 106.97 122.11 165.39120 108.67 124.14 168.11

3.3 Pre-Development Catchment Simulation/Modeling

3.3.1 Hydrological Analysis

The survey plan shows that the catchment runoff will flow to the old existing drain which will discharge to Sungai Tuaran. Base on the survey plan the catchment of this development is not restricted to the 0.922 ha and not including the catchment outside the development boundary.

Input Parameters for Pre-Development

i) Catchment details

Catchment Area (ha)

%, Imp.

Overland Flow

Length

Surface Gradient

(%)

Impervious, n

Pervious, n

101 0.922 95 200 0.815 0.015 0.25

ii) Routing method Linear Reservoir Method Equal length

iii) Infiltration model Horton Equation Depression storage

i. 5 mm for pervious areaii. 1.5 mm for impervious area

Maximum infiltration = 75 mm/hr Minimum infiltration = 3 mm/hr

3.3.2 Hydraulics

The pre-development area is an open area with minimal vegetation and full of earth dirt. The rain water flows to an existing old drainage at the north west of the boundary area or flow towards Sungai Tuaran.

The table below shows the pre-development discharge for different duration for both minor and major storm.

Table : summary of Qpre between 5 min to 180 minutes

Duration (mins)

5 Year ARI 50 Year ARI

Duration (mins)

5 Year ARI 50 Year ARI

5 8010 8515 9020 9530 10035 10540 11045 12050 13055 14060 15065 16070 17075 180

From table above, is it found that the peak discharge for both minor and major storm is as follow.

Storm Storm duration Peak QpreMinor – 5 years 30 minutes 0.168 m3/s

Major – 50 years 30 minutes 0.316m3/s

Input Parameter for Post – Development

i) Catchment Details

Catchment ID

Area (ha)

% Imperviou

s

Overland flow

length

Surface gradient

(%)

Impervious, n

Pervious, n

101 0.5824 95 23 2 0.015 0.25102 0.1150 0 17.8 2 0.015 0.25103 0.2246 100 30 2 0.015 0.25

ii) Routing methoda. Linear reservoir methodb. Equal length

iii) Infiltration model Horton equation Depression storage

i. 5 mm for pervious areaii. 1.5 mm for impervious area

Maximum infiltration Minimum infiltration

3.4 Post Development Catchment Modeling

For the purpose of design analysis, the proposed site has been divided into 3 sub-catchment. A brief explanation and illustration of the drainage network system is shown below.

Catchment ID Area (ha) % Impervious Overland flow length

Surface gradient (%)

Impervious, n Pervious, n

101 0.5824 95 23 2 0.015 0.25102 0.1150 0 17.8 2 0.015 0.25103 0.2246 100 30 2 0.015 0.25

Pond Bottom Area (m2)

Depth (m) DCP Weir Size (m) Orifice diameter, Ø size

(m)18.6 3.0 1.1 @ RL 2.1 1 × 0.19

Hydrographs

A preliminary hydrological analysis is to determine the critical duration which is most likely to produce the peak flow from a rainfall – runoff model. Preliminary hydrologic analysis is based on ARI 5 years to 50 years to determine the peak flow rate. The discharge values at different duration are generated using

Summary of outflow, water level and capacity of the on-site detention facilities.

Pond Peak outflow (m3/s)

Water level Capacity required (m3)

Capacity provided (m3)

101 102 combine 103L1 L2 L3

pondL4

5 years ARI50 Years ARI

4. Maintenance Schedule

Inspection and maintenance of the drainage system shall be carried out on a regular basis to ensure the drainage system is functioning properly. the following are recommendation for drainage maintenance

5. Conclusion

From the above analysis of both the minor and the major storm event, it is concluded that the proposed drainage network systems are sufficient to provide service for the development and the discharge quantity will not affect any surrounding or nearby area.

The proposed development plan and drainage plan was in accordance with JPS MSMA requirement.