Holding From 18 th to 21 st October, 2011 At Palais des Congrès Cotonou, Republic of Benin

Transcription

1 RIPIECSA, IRD, AIRD, AMMA Joint Workshop Extreme Rainfall and its socio economic impacts: Lagos Mega city, Nigeria By Shakirudeen ODUNUGA 1, Ernest AFIESINMAMA 2 & Kolawole MUYIOLU 2 1 Department of Geography, University of Lagos odushak@yahoo.co.uk, sodunuga@unilag.edu.ng, Tel: , Nigeria Meteorological Agency (NIMET) Holding From 18 th to 21 st October, 2011 At Palais des Congrès Cotonou, Republic of Benin

2 Introduction Climate Change; making weather much more variable, rains more uncertain and heavy storms with high intensity more frequent. The consequence of high h intensity it and frequent rainfall in urban environments is flooding The high intensity rainfall coupled with unregulated land uses of Lagos Mega city make the problem more severe.

3 Problem Definition Flooding in most urban areas is localized, but its cumulative effect on the socio-economic, environment and proper functioning of the supporting systems could be monumental. Aim The paper pp examine the Socio-economic impacts of extreme rainfall of 10 th July 2011 in Lagos. Objectives: Dt Determine the deviation iti of f10 th July 2011 Lagos Rainfall from annual lhighest h daily rainfall in July ( ) Identify the causes of loss of lives to the single rainstorm Estimate individual property loss to the storm event Identify the environmental & economic benefits of the urban flood. 1

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5 Land use of Metropolitan Lagos

6 Methodology The percentage deviation of July 10 th storm event tfrom highest daily rainfalls for the month of July for 35 years ( ) was calculated. Focus Group Discussion (FGD) and In-Depth Interview (IDI) were carried out in five highly vulnerable areas (V/I Ikoyi, Orile, Bariga/Ilaje, Iwaya Makoko, Surulere / Itire / Lawanson) ) Also, questionnaires relating to the socio-economic impact of the 10 th July, 2011 storm event were administered in the area. These were supported by media reports.

7 Results and Discussion Characteristics of July 10 Rainfall Location Amount (mm) (Average Intensity /hr) Ikeja Oshodi Event was broad daylight Sunday (weekend) Wadding through unknown terrain

8 July 2011 Extreme Rainfall %) CV ( Oshodi Ikeja Lagos Roof Idi Araba / LUTH Location / Station Over 200% deviation from annual highest daily rainfall in July ( ) Moderate spatial variation Lagos roof and LUTH (5 years Data)

9 Socio-economic impacts of July rainfall in Lagos About 19 lives were lost to the single storm rainfall.

10 Days After

11 Cause of casualties None preparedness for extreme climate events Local emergency services lack the capacity (material and human) to respond to extreme climate phenomenon Inappropriate p local adaptation strategies to extreme flood events Inadequate Knowledge and information about climate change and variability

12 Emergency services lack the capacity to respond to extreme climate phenomenon

13 Damage to Property About 75% out of 320 respondents suffered damage from the July 10 flood event. Th d d d i l d h The goods and property damage include: house utensils, cars, building and other personal belongings.

14 Damage to Property (Contd.) The monetary value of damaged goods and property as indicated by the affected respondents were Amount ($) % Affected $ $ $ Could not quantify The aesthetic values loss and psychological traumas experienced cannot be estimated.

15 Monetary value of loss in Business Monetary value of loss in Business ($) Percent The low income and female gender are particularly vulnerable and were more affected by the June 10 flood event However, males lost more goods and property than females for their loss is on the Total 100 higher values than the losses recorded by females. > No loss in business 54.8 No Response 6

16 Environmental / Economic Benefits of Urban Flood in Lagos Benefit Percent Economic / Monetary 7.2 Social 0.3 Aesthetic 0.6 Other benefit 3.2 No Response Loss 83.1 Total 100

17 Environmental / Economic Benefits of Urban Flood in Lagos (Contd.) The aesthetic benefit: flood sweep off the refuse / debris and clean the drains within the environment. Economic benefit: This is derived by those who commercialised assistance to stranded individuals / motorists. Street urchin made between $ 50 to $ 100:00 from assisting flood victims.

18 Commercial Assistance during flood event in Lagos

19 Economic Benefits (Contd.) The measure of strength of association between July 10 flood experience and benefits derived by respondents show a weak contingency coefficient of There is traces of direct and immediate benefit /by some less privilege individuals. However these benefits are of no significant value that is not However, these benefits are of no significant value that is not worth any consideration in any preventive measures against flooding in Lagos.

20 Conclusion The already strained city of Lagos with over 15 million inhabitants is being put under additional stress with continuous increase in frequency and extent of flooding phenomena. Environmental refugees due to flooding are becoming annual rituals especially amongst the urban poor who live in the blighted environments of Lagos. Increasing urban floods in most parts of Lagos has resulted in damage to houses assets and income to houses, assets and income. Recent phenomenon have shown that flood prevention in Lagos should move beyond drainage improvements to include climate change mitigation and adaptation, communication and local strategies

21 Drainage Improvement on System 2

22 Recommendations Continuous monitoring / modelling of West African Monsoon and Integration of observatory and model results into urban planning activities. Public campaign / awareness, community participation as well as improving the socio economic status of the vulnerable people. A judicious mix of both structural and non structural strategies A judicious mix of both structural and non structural strategies selected with the full participation of stake holders in a bottom top approach.

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