Rain Water Harvesting In Islamabad.docx

Rain water harvesting in Islamabad: Company: CDA (Capital Development Authority)

What is rain water harvesting: Rain water harvesting is a technique of collection and storage of rainwater into natural reservoirs or tanks, or the infiltration of surface water into subsurface aquifers (before it is lost as surface runoff).

Roof top harvesting: One method of rainwater harvesting is rooftop harvesting. With rooftop harvesting, most any surface — tiles, metal sheets, plastics, but not grass or palm leaf — can be used to intercept the flow of rainwater and provide a household with high-quality drinking water and yearround storage. Other uses include water for gardens, livestock, and irrigation, etc. Purpose: The principal is when the rain water falls rather than allowing to simply flow in to the water drain and wasted we store this water and bring it to good use. Islamabad water shortage:

Islamabad is faces heavy water shortage every year. Water level of the city is continuously getting lower and lower. To decrease this burden rain water harvesting project was initiated by CDA in collaboration with UNDP (United Nation Development Program) and PCRWR(Pakistan Council Of Research in water resources) The project was completed in 2011.

Filtration unit: Hidden under metal lids in a forest close to the mosque, there are huge reservoirs. Here the water is filtered with the help of sand filter-beds. After the filter the water runs down vertical pipes up to the ground water level.

Commented [us1]:

These tanks should provide clean drinking water while recharging the local water table for the city’s nearly 1 million residents. Future projects: According to CDA website the project was a huge success and they are planning to open other rain water harvesting projects throughout the city at 20 different locations. The new sites where the Rain Water Harvesting programme would be executed before the monsoon rainfall include drainage of Faisal Avenue Margallah Road and Faisal Mosque, Eastern Ravine of E-7, Western Ravine of E-7, Ravine located at East of E-7, Drainage of Faisal Avenue at F-8/3, Drainage of Faisal Avenue at F-7/2, Drainage of F-7/4 South of Fazl-e-Haq Road, Linear Park between F-6/3 and F-5/2, Children Park in Street 10, F-6/3, Drainage of Club Road, Drainage of Faisal Avenue Shakarparian Chowk and Zero-Point, Runoff from the Park Between I-8 and H-8, Drainage of Shakarparian Chowk, Drainage of I-8 Markaz near Imambargah, Use of abandoned tube-well (8/54) in Sector I-9/4, use of abandoned tube-well (7/55) in Sector I-9/2, AGPR Building G-8, Runoff from I-9/4 and STP.

Calculation:

 Exact project cost of project was not available on CDA or PCRWR website so we have no choice but to suppose that value.  Project Cost: 10,000,000 rs= 10 million RS Water saved depend on the amount of rain fall as we are replacing our normal water use to rain water use. Islamabad climate (according to Wikipedia) Climate data for Islamabad (1961–1990) Month

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Average precipitation 56.1

73.5

89.8

61.8

39.2

62.2

267.0

309.9

98.2

29.3

17.8

37.3

mm (inches)

(2.21) (2.89) (3.54) (2.43) (1.54) (2.45) (10.51) (12.20) (3.87) (1.15) (0.70) (1.47

Rain fall is measured in millimeter precipitation. Rain gauge is an meteorological instrument for determine the depth of precipitation (usually in mm) that occurs over a unit area (usually one meter squared) and thus measuring rainfall amount. One millimeter of measured precipitation is the equivalent of one liter of rainfall per meter squared. Rain fall/ year

=1142.1 mm precipitation =1142.1 liter/ m^2

Area of Feisal mosque

= 5000 m^2

Water saved/ year

=5000*1142.1 =5,710,500 liter

Water price

=2 RS/liter (supposed)

Money saved/ year

=2*5710500*2 =11,421,000 rs

Water saved per month depend on the month chosen. Water saved/month(august)

=5000*39.2 =1549500 Liters

Money saved/ month(august)

=1549500*2 =3,099,000 RS

Water saved/ day(august)

=1549500 liters/30 = 51650 liters

Money saved/ day

=51650*2 =103,300 RS

Water saved /10 years

=5,710,500 liter*10 =57,105,000 liters

Money saved/10 years

=114,210,000 rs

By using micro soft excel we found Month water saved liters money saved (rs)

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Year

280500

367500

449000

309000

196000

311000

1335000

1549500

491000

146500

89000

186500

5710500

561000

735000

898000

618000

392000

622000

2670000

3099000

982000

293000

178000

373000

11421000

Life cycle cost analysis:

 Project Cost: -10,000,000 rs= 10 million RS(supposed)  Maintenance cost=-5 million( supposed)  Money saved/10 years

=+114,210,000 rs

 Disposal cost =-1 million  Total Life Cycle cost = Total costs (Price,maintenance, disposal)  Life cycle cost=114,210,000-1,000,000-5,000,000  Life cycle cost=108210000 RS

https://www.dawn.com/news/515174 https://www.dw.com/en/islamabad-to-harvest-rain-water/a-5787215 https://en.wikiversity.org/wiki/Rainwater_harvesting

http://www.sciencevision.org.pk/BackIssues/Vol19/07_Vol19_Rainwater_Harv esting_Potential_Sites_BushraKhalid.pdf