Assumptions For this design project assumption has been made. As for the vegetables, “broccoli” has been as a representative vegetable. Table 1: Maize Characteristics (Source: FAO) Crop characteristic Initial Crop Development Mid- season Late Total Period (Days) 20 35 40 30 125 Depletion Coefficient, p - - - - 0.50 Root Depth, m 0.25 - - 0.8 - Crop Coefficient, Kc 0.4 0.8 1.15 0.7 -

Table 2: Vegetable (broccoli ) Characteristics Crop characteristic Initial Crop Development Mid- season Late Total Period (Days) Depletion Coefficient, p - - - - 0.45 Root Depth, m - - 0.4 - Crop Coefficient, Kc -

Table 3: Data used to design the sprinkler irrigation system

Parameters Crops Maize Vegetables

Area to be irrigated (ha) 5.086 1.637 Soil Sandy loam Bulk Density (g/cm3) 1.45 Soil infiltration Capacity (mm/h) 14 Peak daily water use (ETc) 5 5 Soil moisture at field capacity (FC) 0.34 Soil moisture at permanent wilting point (PWP) 0.20 Root zone depletion (RZD) (m) 1.5 Application Efficiency 80% Average wind Speed (m/s) 3 (10.8 km/h)

1

Methodology The methodology followed was adopted from procedures set by FAO 2001. The reason for using this methodology is that it is clear and specific. In addition it is applicable worldwide for a smallholder farms. Following are the step by step calculations.

Net depth of water application The depth of water application is the quantity of water, which should be applied during irrigation in order to replenish the water used by the crop during evapotranspiration.

The maximum net depth to be applied per irrigation can be calculated, using the following equation:

𝑑𝑛𝑒𝑡 = 1000 × 𝑝(𝜃𝐹𝐶 − 𝜃𝑃𝑊𝑃) × 𝑍𝑅

Where:

𝑑𝑛𝑒𝑡 = readily available moisture or net depth of water application per irrigation for the selected crop (mm)

𝜃𝐹𝐶 = soil moisture at field capacity

𝜃𝑃𝑊𝑃 = soil moisture at the permanent wilting point

𝑍𝑅 = the depth of soil that the roots exploit effectively (m)

𝑝 = the allowable portion of available moisture permitted for depletion by the crop before the next irrigation

For Maize

𝑑𝑛𝑒𝑡𝑀𝑎𝑖𝑧𝑒 = 1000 × 0.5 × (0.34 − 0.20) × 0.8

𝑑𝑛𝑒𝑡𝑚𝑎𝑖𝑧𝑒 = 56 𝑚𝑚

For Vegetable (broccoli)

𝑑𝑛𝑒𝑡𝑉𝑒𝑔𝑒𝑡𝑎𝑏𝑙𝑒 = 1000 × 0.45 × (0.34 − 0.20) × 0.4

𝑑𝑛𝑒𝑡𝑣𝑒𝑔𝑒𝑡𝑎𝑏𝑙𝑒 = 25.2 𝑚𝑚

Volume to be applied In order to express the depth of water to be applied in terms of the volume, the proposed area for irrigation must be multiplied by the depth

The volume to be applied is calculated using the following formula.

𝑉 = 10 × 𝐴 × 𝑑𝑛𝑒𝑡

Where:

2

𝑉 = Volume of water to be applied (m³)

𝐴 = Area proposed for irrigation (ha)

𝑑𝑛𝑒𝑡= Depth of water application (mm)

For Maize:

𝑉𝑚𝑎𝑖𝑧𝑒 = 10 × 5.086 × 56

𝑉𝑚𝑎𝑖𝑧𝑒 = 2848.16 𝑚3

For Vegetable

𝑉𝑣𝑒𝑔𝑒𝑡𝑎𝑏𝑙𝑒 = 10 × 1.637 × 25.2

𝑉𝑣𝑒𝑔𝑒𝑡𝑎𝑏𝑙𝑒 = 412.52 𝑚3

Irrigation Frequency at peak demand and Irrigation cycle The peak daily water use is the peak daily water requirement of the crop determined by subtracting the rainfall (if any) from the peak daily crop water requirements.

Irrigation frequency is the time it takes the crop to deplete the soil moisture at a given soil moisture depletion level.

Irrigation frequency

𝐼𝐹 =𝑑𝑛𝑒𝑡𝐸𝑇𝐶

Where:

𝐼𝐹 = irrigation frequency (days)

𝑑𝑛𝑒𝑡 = net depth of water application (mm)

𝐸𝑇𝐶 = peak daily water use (mm/day)

For Maize :

𝐼𝐹𝑚𝑎𝑖𝑧𝑒 =56 𝑚𝑚

5 𝑚𝑚/𝑑𝑎𝑦

𝐼𝐹𝑚𝑎𝑖𝑧𝑒 = 11.2 𝑑𝑎𝑦𝑠

For Vegetables:

𝐼𝐹𝑣𝑒𝑔𝑒𝑡𝑎𝑏𝑙𝑒𝑠 =25.2 𝑚𝑚

5 𝑚𝑚/𝑑𝑎𝑦

𝐼𝐹𝑣𝑒𝑔𝑒𝑡𝑎𝑏𝑙𝑒𝑠 = 5.04 𝑑𝑎𝑦𝑠

3

The system should be designed to provide 56 mm every 11.2 days and 25.2mm for every 5.04 days for maize and vegetables respectively. For practical purposes, fractions of days are not used for irrigation frequency purposes. Hence the irrigation frequency in design should be 11 days, with a corresponding dnet of 55 mm (5 x 11) and a moisture depletion of 0.49 (55/(1000x0.8x(0.34-0.20)) for maize and 5 days, with corresponding dnet of 25 mm (5 x 5) and moisture depletion of 0.45 (25/(1000x0.4x(0.34-0.20)) for vegetables To allow for all practical purposes and in order to accommodate the time for cultural practices (spraying etc), it is advisable that irrigation is completed in less than the irrigation frequency. In this case, 10 days irrigation and 1 day without irrigation for maize while 4 days and 1 day without irrigation for vegetables is considered adequate. The time (10 days for maize and 4 days for vegetables) required to complete one irrigation in the area under consideration is called Irrigation cycle.

Gross depth of water application

The gross depth of water application (equals the net depth of irrigation divided by the farm irrigation efficiency. It should be noted that farm irrigation efficiency includes possible losses of water from pipe leaks.

𝒅𝒈𝒓𝒐𝒔𝒔 =𝒅𝒏𝒆𝒕𝑬𝒂

Where:

𝑬𝒂= Application efficiency = 0.8

For maize

𝒅𝒈𝒓𝒐𝒔𝒔𝒎𝒂𝒊𝒛𝒆 =𝟓𝟓 𝒎𝒎𝟎.𝟖

𝒅𝒈𝒓𝒐𝒔𝒔𝒎𝒂𝒊𝒛𝒆 = 𝟔𝟖.𝟖 𝒎𝒎

For vegetables:

𝒅𝒈𝒓𝒐𝒔𝒔𝒗𝒆𝒈𝒆𝒕𝒂𝒃𝒍𝒆𝒔 =𝟐𝟓 𝒎𝒎𝟎.𝟖

𝒅𝒈𝒓𝒐𝒔𝒔𝒗𝒆𝒈𝒆𝒕𝒂𝒃𝒍𝒆𝒔 = 𝟑𝟏.𝟑 𝒎𝒎

4

Preliminary system capacity This is theoretical system design. The system capacity (Q), can be calculated using the following equation;

𝑄 = �10 × 𝐴 × 𝑑𝑔𝑟𝑜𝑠𝑠𝐼 × 𝑁𝑆 × 𝑇

�

Where:

𝑄 = Theoretical system capacity (m³/hr)

𝐴 = Design area (ha)

𝑑𝑔𝑟𝑜𝑠𝑠 = gross depth of water application (mm)

𝐼 = irrigation cycle (days)

𝑁𝑆 = number of shifts per day

𝑇 = irrigation time per shift (hr)

In our design, the area to be irrigated is 5.086 ha for maize and 1.637 ha for vegetables. In order to

achieve the maximum degree of equipment utilization, it is desirable, but not always necessary, that the

irrigation system should operate for 5 hours per shift at 2 shifts per day during peak demand and take

an irrigation cycle of 10 and 4 days complete irrigating the 5.086 and 1.637 ha respectively.

𝑄𝑚𝑎𝑖𝑧𝑒 = �10 × 5.086 × 68.8

10 × 2 × 8�

𝑄𝑚𝑎𝑖𝑧𝑒 = 21.87 𝑚3 ℎ⁄

𝑄𝑣𝑒𝑔𝑒𝑡𝑎𝑏𝑙𝑒𝑠 = �10 × 1.637 × 31.3

4 × 2 × 8�

𝑄𝑣𝑒𝑔𝑒𝑡𝑎𝑏𝑙𝑒𝑠 = 8 𝑚3 ℎ⁄

𝑄𝑡𝑜𝑡𝑎𝑙 = 𝑄𝑚𝑎𝑖𝑧𝑒 + 𝑄𝑣𝑒𝑔𝑒𝑡𝑎𝑏𝑙𝑒𝑠

𝑄𝑡𝑜𝑡𝑎𝑙 = 21.87 + 8 = 29.87 8 𝑚3 ℎ⁄

5

Sprinkler selection and spacing The selection of the correct sprinkler depends on how best fit spacing with a certain pressure and

nozzle size can provide the water at an application rate that does neither cause runoff nor damage the

crop and at the best possible uniformity under the prevailing wind conditions. The selected sprinkler

should fully satisfy the irrigation water requirements and the irrigation frequency.

It is therefore necessary to know the infiltration rate of the soil before we can proceed with sprinkler

selection.

It should be pointed out that in order to avoid runoff the sprinkler application rate should not exceed the

basic soil infiltration rate. Hence, the basic infiltration rate of the soil is used as a guide to select a

sprinkler with a precipitation rate lower than the infiltration rate.

6

Table 4: Performance of some sprinkler (FAO)

Selected sprinkler from the table 4;

A 12 m x 12 m spacing for the 3.0 mm nozzle operating at 400 kPa pressure and delivering 1.52m³/hr at 10.56 mm/hr precipitation rate. It has a wetted diameter of 33.05 m.

Checking the Precipitation Rate

Soil in�iltration rate > 𝑠𝑝𝑟𝑖𝑛𝑘𝑙𝑒𝑟 𝑝𝑟𝑒𝑐𝑖𝑝𝑖𝑡𝑎𝑡𝑖𝑜𝑛 𝑟𝑎𝑡𝑒

Since 14 mm h⁄ > 10.56 mm h⁄ then it is 𝐎𝐊

Checking Weather Satisfy the Wind Requirements

From the given data, Average wind velocity is 10.8 km/h. From table 5 sprinkler spacing should be

based on 50% of D for square pattern.

𝑀𝑎𝑥𝑖𝑚𝑢𝑚 𝑆𝑝𝑎𝑐𝑖𝑛𝑔 = 50% 𝑜𝑓 𝐷 × 50% 𝑜𝑓 𝐷

Where D = Wetted diameter

50% 𝑜𝑓 𝐷 = 0.5 × 33.05 𝑚 = 16.5 𝑚

𝑀𝑎𝑥𝑖𝑚𝑢𝑚 𝑆𝑝𝑎𝑐𝑖𝑛𝑔 = 16.5 𝑚 × 16.5 𝑚 𝑤ℎ𝑖𝑐ℎ 𝑖𝑠 𝑔𝑟𝑒𝑎𝑡𝑒𝑟 𝑡ℎ𝑎𝑛 12 𝑚 × 12 𝑚

Hence wind requirement is Satisfied

7

Table 5: Sprinkler Characteristics Spacing 12 m x 12 m Nozzle diameter 4.5 mm nozzle operating 400 kPa Precipitation 10.56 mm/hr Discharge 1.52 m³/hr Wetted diameter 33.05 mm Table 6: Maximum sprinkler spacing as related to wind, square pattern

Layout and final design The system layout is obtained by matching the potentially acceptable spacing with the dimensions of the field such that as small land as possible is left out of the irrigated area. The layout should also accommodate access roads, drains and other structures.

Set time This is the time each set of sprinklers should operate at the same position in order to deliver the gross irrigation depth.

𝑇𝑆 =𝑑𝑔𝑟𝑜𝑠𝑠𝑃𝑟

Where:

𝑇𝑆 = set time (hr)

𝑃𝑟 = sprinkler precipitation rate (mm/hr)

𝑇𝑆𝑚𝑎𝑖𝑧𝑒 =55 𝑚𝑚

10.56 𝑚𝑚/ℎ𝑟

𝑇𝑆𝑚𝑎𝑖𝑧𝑒 = 5.2 ℎ𝑜𝑢𝑟𝑠

𝑇𝑆𝑣𝑒𝑔𝑒𝑡𝑎𝑏𝑙𝑒𝑠 =25 𝑚𝑚

10.56 𝑚𝑚/ℎ𝑟

8

𝑇𝑆𝑣𝑒𝑔𝑒𝑡𝑎𝑏𝑙𝑒𝑠 = 2.37 ℎ𝑜𝑢𝑟𝑠

Hence, each set of sprinklers should operate at the same position for 5.2 hours and 2.4 hours in order to deliver the 55 and 25 mm gross application depth per irrigation for maize and vegetables respectively.

System capacity The capacity of such a system can be calculated using the following equation;

𝑄 = 𝑁𝑆 × 𝑁𝐶 × 𝑄𝑆

Where:

𝑄 = system capacity (m³/hr)

𝑁𝐶= the number of laterals operating per shift

𝑁𝑆 = the number of sprinklers per lateral

𝑄𝑆 = the sprinkler discharge (from the manufacturer's tables)

For Maize field

𝑁𝑠 =188 𝑚12 𝑚

= 16 𝑠𝑝𝑟𝑖𝑛𝑘𝑙𝑒𝑟𝑠

𝑁𝐶 = 1 𝑙𝑎𝑡𝑒𝑟𝑎𝑙 𝑝𝑒𝑟 𝑠ℎ𝑖𝑓𝑡

𝑄𝑚𝑎𝑖𝑧𝑒 = 16 × 1 × 1.52

𝑄𝑚𝑎𝑖𝑧𝑒 = 24.32 𝑚3 ℎ⁄

For Vegetable’s field

𝑁𝑠 =150 𝑚12 𝑚

= 13 𝑠𝑝𝑟𝑖𝑛𝑘𝑙𝑒𝑟𝑠

𝑁𝐶 = 1 𝑙𝑎𝑡𝑒𝑟𝑎𝑙 𝑝𝑒𝑟 𝑠ℎ𝑖𝑓𝑡

𝑄𝑣𝑒𝑔𝑒𝑡𝑎𝑏𝑙𝑒 = 13 × 1 × 1.52

𝑄𝑣𝑒𝑔𝑒𝑡𝑎𝑏𝑙𝑒 = 16.76 𝑚3 ℎ⁄

𝑄𝑡𝑜𝑡𝑎𝑙 = 𝑄𝑚𝑎𝑖𝑧𝑒+𝑄𝑣𝑒𝑔𝑒𝑡𝑎𝑏𝑙𝑒

9

𝑄𝑡𝑜𝑡𝑎𝑙 = 24.32 + 16.76

𝑄𝑡𝑜𝑡𝑎𝑙 = 41.08 𝑚3 ℎ⁄

Comparing to theoretical capacity (preliminary system capacity) calculated earlier at 29.87 m³/hr for a

10 and 4 days cycle for maize and vegetables respectively, this flow (41.08 m³/hr) is higher. Hence less

than initial maximum discharge (80 m3/h) is required (41.08 m3 h⁄ ) .

Allowable pressure variation To achieve high uniformity, pressure differences throughout the system or block or subunit should be maintained in such a range. For practical purposes the allowable pressure loss due to friction should not exceed 20% of the sprinkler operating pressure.

In our example, of the 12m x 12 m spacing for the 3.0 mm nozzle operating at 400kPa, the allowable pressure variation in the system should not exceed 20% of the sprinkler operating pressure, which is 80 kPa (400 x 0.2) or 8 meters.

THIS IS THE END OF THE PART THE PART DONE

10

Pipe size determination Pipe size determination involves selecting the diameter of a pipe type, which can carry discharge at or below the recommended velocity limit. A spreadsheet was used to calculate this.

Laterals Laterals in a semi-portable system are aluminum pipes with multi-outlets (sprinklers) along their length. The friction losses, either calculated or obtained from charts, have to be corrected since the flow reduces along the lateral.

11

Figure 1: Output of excel sheet for designing of less than 20 laterals

The pipe diameter selected was 0.05m for laterals. This is because the pipe is cheaper and available on the market. The head loss obtained from FAO charts according to the discharge of the lateral is 0.5m/100m

The maximum length of the lateral in this design is 48 metres. It will have 5 sprinklers operating at the same time, delivering 0.57m³/hr each at 250 KPa pressure. Therefore the flow at the beginning of the lateral will be:

Q = 5 x 0.57

= 2.85 m³/hr.

According to the friction loss chart for aluminium laterals a 50 mm diameter pipe would have a friction loss of 0.5 m per 100 m of pipe (0.5%). If the pipe was just a blind pipe (i.e. without multi-outlets) then the friction loss for a discharge of 2.85m³/hr would be:

HL = 0.005 x 48 = 0.24 m

By taking into consideration the "F" factor corresponding to 5 outlets (sprinklers),

HL = 0.005 x 48 x 0.440 = 0.1056m

12

Assuming that each valve hydrant would serve 2 lateral positions, then the friction losses for the 48 m aluminium pipe (header) with a flow of 2.85m³/hr should be included in the friction losses for the lateral:

HL = 0.005 x 5 = 0.025 m for the 50 mm pipe.

Therefore the total friction losses in the 50 mm lateral, when the header is used, are;

0.1056 + 0.025 = 0.13 m.

Main Line It is necessary to know some characteristics of some of the pipes commonly used in irrigation, unplasticized Polyvinylchloride (uPVC) pipes.

The pressure within any part of the pipe network should not exceed the working pressure of that pipe, in order to comply with established standards. This should be kept in mind when selecting pipe sizes for frictional loss calculations. In addition, the recommended maximum velocities of around 2 m/should not be exceeded.

The position of each lateral affects the friction losses in the main line since it affects the flow at the different sections of the main line. Therefore, friction losses corresponding to different alternative positions of the laterals should be analyzed. Friction losses in the main are calculated for the first, middle and last positions. Using the frictional loss chart for uPVC pipes, the friction losses of the main line can be calculated as shown below.

Q = the discharge or flow rate within that section of the pipe (m³/hr)

L = the length of pipe for that section (m)

D = the pipe size diameter (mm)

HL = the friction loss of the pipe (m)

Pipe class shows the working pressure of the pipe, not to be exceeded in that section. The frictional loss charts also show the recommended maximum velocities of flow in the pipes. The smaller the velocity, the less the head loss per unit length of pipe. The higher the flow, the higher the friction loss per unit length and the more it is turbulent. This leads to the possibility of higher internal wear of the pipe and possibility of water hammer, when the system is shut down suddenly.

As a guideline in selecting the class of a pipe to be used, it is suggested that the sum of the difference in elevation, sprinkler operating pressure, allowable pressure variation and lateral friction losses is used.

In this case:

- Difference in elevation = 0.01 meters (gentle slope)

- Sprinkler operating pressure = 25 meters

- 20% allowable pressure variation = 0.2 x 25 = 5 meters

13

- Lateral friction losses = 0.13 meters

The total of 30.14 (0.01 + 25 +5 + 0.13) meters, Since we have a total head loss is about 40metres, then the pipe we shall use is the one with pressure rating of class 4 uPVC.

Qtotal = 5.7 m³/hr (system capacity)

L= 100 m

D= 75 mm class 4 uPVC

H= 0.03 x 100 = 3.00 m

Therefore the head loss in the mail line, HL (main) is 3 m. In this case, the sprinkler operating pressure (SOP) is 25 meters. Therefore the total allowable pressure variation should not exceed 5.00 m (i.e. 20% of SOP = 25 x 0.20). The calculated friction losses of lateral, 0.13 m, and of main, 3 m, plus the difference in elevation of 0.01 m add up to 3.14 m.

Total head requirements The total head requirements are composed of the pump suction lift, the friction losses in the supply line, the friction losses; in the main, lateral and fittings, the riser, the sprinkler operating pressure and the difference in elevation. The suction lift is the difference in elevation between the water level and the eye of the pump impeller plus the head losses in the suction pipe. The head losses of the suction pipe comprise the frictional losses of the pipe, fittings and the velocity head. The friction losses of the suction pipe are insignificant compared to the velocity head, if the pipe is short.

The velocity head is equal to

2

2VH

g=

Where:

v = water velocity (m/s)

g = acceleration due to gravity (9.81 m/s²)

FAO 2001 recommends that for centrifugal pumps, the diameter of the suction pipe should be selected such that the water velocity is not more than 3.3 m/s. This ensures good pump performance.

Therefore the velocity head 23.3

2 9.81H =

×

= 0.56m

In this case, the puisard is assumed to be at 3 m deep and the pump should be on the surface (i.e the eye of the impeller).

Since the maximum velocity head is 0.56 m, therefore the suction lift is 3.56 m (i.e)(3 + 0.56).

14

Assuming minor losses in fittings and a short suction pipe, the suction lift is rounded up to 2 m.

The difference in elevation is 3 meter this is the difference between the ground level of the sprinkler, located at the highest point, and the eye of the pump impeller.

The length of the supply line is 1m; the friction losses for the supply line are computed as follows:

Q = 5.7 m³/hr

L = 1 m

D = 90 mm

HL = 0.05 x 1 = 0.05 m

For friction losses in the riser; it was assumed to be about 0.25 m per m of the total length of the riser. Therefore the head loss in Risers is 0.25m/m x 1m = 0.25m

For fittings, 10% of the total head losses were assumed.

Table 3: Calculation of total dynamic head Total Dynamic Head Component Head loss (m)

Suction Lift 3.56 Supply line 0.05 Main line 3.14 Lateral 0.13 Riser 0.25 Sprinkler Operating Pressure 25.00 Subtotal 32.13 Fittings (10% of subtotal) 3.21 Elevation difference 3.00 Total 38.34

Pump selection and power requirements The most important criteria in the selection of a pump is that, the Net Positive Suction Head Available (NPSHA) exceeds the Net Positive Suction head Required (NPSHR) by the pump.

From the manufacturer’s charts, a pump which should provide the desired head and flow at the highest possible efficiency and an electric motor to drive the pump should be selected.

The basic formula for power requirement (kW) calculations is provided below:

360Q TDHkW

Ep ×

= ×

Where:

kW = energy transferred from the pump to the water in kW

15

Q = discharge (m3/hr)

TDH = total dynamic head (m)

Ep = the pump efficiency (%) from the pump performance charts

It should be noted that this formula is an expression of the actual power required at the pump.

Power requirements then is 5.7 40360 0.7

kW × = ×

= 0.905kW

Depending on the losses in transferring the power to the pump, an allowance of 20% should be added to the requirement.

Therefore this came up to 1.086KW

Therefore a pump with not less than 1.086 KW is required for this design. Depending on the manufacturer and market availability, the next larger size of motor or engine should be obtained.

Conclusion and Recommendation The efficient and effective semi-portable sprinkler irrigation systems intended for pepper has been designed based on the crop water requirements, soil condition, climatic condition and the water source capacity. Therefore, if a farmer wants to adopt the design, they have to look into the capacity of their water source and the crop to be cultivated. The use of pressurized irrigation systems is a viable alternative for efficient water use, particularly in agricultural areas where water is in short supply.

References Allen, R., Pereira, L.S., Raes, D., and M. Smith. 1998. Crop evapotranspiration—guidelines for

computing crop water requirements. FAO Irrigation and Drainage Paper No. 56. Rome, Italy.

Barry S., Illy L., Kargougou I., Kondé M., Ouédraogo S., Parkouda S., Sana G.A. and D. Yamégo. 1998. Etude sur la typologie des exploitations agricoles familiales et adoption d’une nouvelle stratégie agricole. Rapport définitif. Ouagadougou, FAO, 149 p. http://www.fao.org/nr/water/cropinfo_pepper.html (Accessed on 23/11/08)

16

Direction Regionale l’agriculture, de l’Hydraulique. 2004. Etude orphopedologique du bassin versant

de la vallee du kou, Boobo Dioulasso, Burkina faso. 32p. FAO. 2001. Irrigation Manual Planning, Development, Monitoring and Evaluation of Irrigated

Agriculture with farmer participation. Volume III, Module 8. Harare, Zimbabwe.

Appendix

Table 7: Performance of some sprinklers (Source; FAO, 2001)

Table 8: Sprinkler Characteristics Spacing 12 m x 12 m

Nozzle diameter 3.0 mm nozzle operating 250 kPa Precipitation 3.96 mm/hr Discharge 0.57m³/hr Wetted diameter 25 mm

17

Figure 2: Head losses in Aluminium pipes (Source: FAO, 2001)

18

Figure 3: Frictional loss chart for uPVC pipes (Source; FAO, 2001)

19

Figure 4: Drawing of proposed riser

Figure 5: Sprinkler Head

20

21