Mapping Water Resources and Reservoirs for Climate Resilience in Zambezi River Basin

Transcription

1 Mapping Water Resources and Reservoirs for Climate Resilience in Zambezi River Basin Corné van der Sande, NEO BV Senior Advisor Earth Observation Services for Monitoring Drought and Water Resources in support of Disaster Reduction and Recovery Netherlands Space Office, The Hague, November 14, 2012

2 Presentation outline Our spatial context Earth Observation for Development EOWorld Mapping Small Reservoirs Feedback from the customer

3 Our spatial context NEO s mission: to assist governments and businesses in the sustainable improvement of location based information. Better information enhances decision taking and planning by our customers. In this way we contribute to this rapidly changing world Everything is in a map in the Netherlands A map is useless if you do not keep it up to date Change signal: New building Mapped building Lines: New Changed Disappeared Map Objects: Disappeared (WAS) New (Becomes)

4 Our spatial context Open data becomes common: From 2013 ESA will launch Sentinel satellites Data to become available from 2015 > Will bring major innovations to the geoworld

5 Our spatial context Drought monitoring since the beginning DRYMON provides insight into the development and geographical extent of dry and wet conditions on a daily basis anywhere on the globe Kansas State, soil moisture 2012 Kansas State, soil moisture normal year

6 Our spatial context Integration online: Collect Combine Decide

7 Earth Observation for Development Partnership ESA and Worldbank 12 projects around the globe executed by remote sensing companies in related to: Disaster Risk Management Urban Development Agriculture and Forest Management Water Resources Management Coastal Zones Management Marine Environment Climate Change Adaptation Projects by NEO: Assessing Vulnerability in the Metropolitan Area of Rio de Janeiro to Landslides land use map, landslide risk maps Watershed Mapping and Water Resources Management Prioritization for the Zambezi River Basin South-Malawi: land use maps, land use change map, erosion hazard map Lake Malawi: water height, water temperature and water quality maps Southern Zambia Province: small reservoirs map

8 Mapping Small Reservoirs Project Context: Small reservoirs are important sources of water to bridge gaps in rainfall Uses are multiple, ranging from irrigation, watering cattle, fishing, recreation, household water, to building materials Where are these reservoirs? Comprehensive overview is needed for Southern Province Field inventory using hand-held GPS just started in March 2011 Set up of water rights database together with a taxing system

9 Mapping Small Reservoirs Method Small Reservoirs - Base Map - Mapping small reservoir well established technique - AOI: Southern province of Zambia - Using landsat 5 for initial mapping April-May 2010/ Extent validated and adjusted using NEO s SignalEyes

10 Mapping Small Reservoirs Method Small Reservoirs Time Series - Based on Envisat ASAR dual-pol images, twice monthly available - Use of different polarisations - Semi-automation - Extent adjusted and validated using NEO s SignalEyes

11 Mapping Small Reservoirs Base Map of 1022 reservoirs

12 Mapping Small Reservoirs Time-series of individual reservoirs - Twice monthly coverage is possible using ASAR - Extent - Capacity Capacity based on Suwanyuma et al. (2006) - Field study in Limpopo basin Zimbabwe of 12 reservoirs - Regression equations were transformed to storage capacity area relationship using basic logarithmic principles.

13 Feedback from the customer Workshop at the Water Board of the Ministry of Energy and Water Development, Lusaka, Zambia at February 10, 2012

14 Feedback from the customer Workshop at the Water Board of the Ministry of Energy and Water Development, Lusaka, Zambia at February 10, 2012

15 Feedback from the customer Comparing Earth Observation with field work Comments on base map: Fast track way to get an overview Misclassifications due to unclear definition: wetlands and road pitches Scale up! Link to field data and water rights Overlapping reservoirs: 145 Direct field workers to remaining 136!

16 Feedback from the customer Field work volume and extent: Dam Wall on Left Bank Position of Stream/River Dam Wall on right Bank Water Level Calculation of volume using SRTM 90 m DEM Comments on volume: Volume by field workers: 388,000 m3 Volume by NEO: 380,294 m3 Volume by design plan: 4,800,000 m3

17 Feedback from the customer Overall appraisal Strengths Free satellite data to build a base map Easy overview of small reservoirs in extent Local authorities are directed towards new reservoirs (just drive and map) Free GIS and Remote Sensing is available for analysis. Weaknesses Volume is likely unreliable A basemap is a waste of money if the owner of the map does not have resources / strategies to keep it up to date Remote sensing expertise needed and supervision in creation of the maps Downloading of data is a problem This week a training is hosted by the World Bank to local government staff, financed by ESA and executed by ITC

18 Questions?