Indicator 11.3.1 Ratio of land consumption rate to population growth rate

Make cities and human settlements inclusive, safe, resilient and sustainable]

By 2030, enhance inclusive and sustainable urbanization and capacity for participatory, integrated and sustainable human settlement planning and management in all countries]

Ratio of land consumption rate to population growth rate]

2024]

11.2.1: Proportion of population that has convenient access to public transport, by sex, age and persons with disabilities

11.6.2: Annual mean levels of fine particulate matter (e.g. PM2.5 and PM10) in cities (population weighted)

11.7.1: Average share of the built-up area of cities that is open space for public use for all, by sex, age and persons with disabilities

11.a.1: Proportion of population living in cities that implement urban and regional development plans integrating population projections and resource needs, by size of city

15.1.2: Proportion of important sites for terrestrial and freshwater biodiversity that are covered by protected areas, by ecosystem type

11.7.2: Proportion of persons victim of physical or sexual harassment, by sex, age, disability status and place of occurrence, in the previous 12 months

11.b.1: Proportion of local governments that adopt and implement local disaster risk reduction strategies in line with the Sendai Framework for Disaster Risk Reduction 2015-2030 [a]]

Kenya National Bureau of Statistics]

Manager, Cartography/GIS]

Cartography/GIS Division]

Undertake Geospatial data collection, compilation, integration, analysis and dissemination. Develop and manage geospatial data bases]

2911000/1,3317612/22/23/51]

P.O Box 30266-00100]

dpss@knbs.or.ke]

Definitions:

The indicator is defined as the ratio of land consumption rate to population growth rate. It requires defining the two components of population growth and land consumption rate. Computing the population growth rate is more straightforward and more readily available, while land consumption rate is slightly challenging, and requires the use of new techniques. In estimating the land consumption rate, one needs to define what constitutes “consumption” of land since this may cover aspects of “consumed” or “preserved” or available for “development” for cases such as land occupied by wetlands. Secondly, there is not one unequivocal measure of whether land that is being developed is truly “newly-developed” (or vacant) land, or if it is at least partially “redeveloped”. As a result, the percentage of current total urban land that was newly developed (consumed) will be used as a measure of the land consumption rate. The fully developed area is also sometimes referred to as built up area.]

City or urban area - The Degree of Urbanisation (DEGURBA) endorsed by the United Nations Statistical Commission, in its 51st Session (March 2020) is the workable method used to delineate cities, urban and rural areas for international statistical comparisons in this indicator. This definition combines population size and population density thresholds to classify the entire territory of a country along the urban-rural continuum, and captures the full extent of a city, including the dense neighborhoods beyond the boundary of the central municipality.

For the computation of this indicator (11.3.1), Kenya has adopted the DEGURBA to define the analysis area (city or urban area).

Population growth rate (PGR) is the change of a population in a defined area (country, city, etc) during a period, usually one year, expressed as a percentage of the population at the start of that period. It reflects the number of births and deaths during a period and the number of people migrating to and from the focus area. In SDG 11.3.1, this is computed at the area defined as urban/city.

Land consumption within the context of indicator 11.3.1 is defined as the uptake of land by urbanized land uses, which often involves conversion of land from non-urban to urban functions.

Land consumption rate is the rate at which urbanized land or land occupied by a city/urban area change during a period of time (usually one year), expressed as a percentage of the land occupied by the city/urban area at the start of that time.

Built up area within the context of indicator 11.3.1 is defined as all areas occupied by buildings.

For the two components used to compute of this indicator, i.e a) land consumption rate and b) population growth rate, the unit of measurement is a percentage (%) value.

The resulting indicator is measured as a ratio of these two percentages making it unitless.]

Dependent on the international classifications of boundaries as per: https://unstats.un.org/unsd/statcom/51st-session/documents/BG-Item3j-Recommendation-E.pdf ]

Population data required for this indicator is available from Kenya National Bureau of Statistics]

1km2 gridded population is available from KNBS

Built up data is available from Kenya Space Agency and land cover from the Directorate of Remote Sensing and Resource Surveys]

Data for this indicator combines earth observation i.e. satellite imagery – land cover- and built-up layers, gridded population data from the Census and geospatial analysis using Google Earth Engine.

Every 3 – 5 years]

Annually]

Global Human Settlement Layer (GHSL) team, Kenya National bureau of Statistics, Directorate of Resource Survey and Remote Sensing, Kenya Space Agency]

Kenya National Bureau of Statistics]

Kenya National Bureau of Statistics

Kenya National Bureau of Statistics (KNBS) is established under the Statistics Act, 2006 as the principal agency of the Government for collecting, analyzing and disseminating statistical data in Kenya and as the custodian of official statistical information.]

Globally, land cover today is altered principally by direct human use: by agriculture and livestock raising, forest harvesting and management and urban and suburban construction and development. A defining feature of many of the world’s cities is an outward expansion far beyond formal administrative boundaries, largely propelled by the use of the automobile, poor urban and regional planning and land speculation. A large proportion of cities both from developed and developing countries have high consuming suburban expansion patterns, which often extend to even further peripheries. Global studies have shown that there is on average three times growth on urban land cover compared to the urban population in several cities across the world while in some cases, similar studies at national level have shown a growth of between three to five times growth in urban (building) land cover. In order to effectively monitor land consumption growth, it is not only necessary to have the information on existing land use cover but also the capability to monitor the dynamics of land use resulting out of both changing demands of increasing population and forces of nature acting to shape the landscape.

The indicator is important as cities require an orderly urban expansion that makes the land use more efficient. They need to plan for future internal population growth and city growth resulting from migrations and to accommodate new and thriving urban functions such as transportation routes, etc., as they expand.]

Interpretation of the many factors at play in relation to describing the land consumption ratio makes it difficult to generalize the implication of a single LCRPGR value to sustainable urbanization. For example, while a value less than 1 could be a good indicator of urban compactness and its associated benefits, intra-city analysis may reveal high levels of congestion and poor living environments, which is against the principles of sustainable development. On the other hand, a value of one may not mean an optimal balance between spatial growth of urban areas and their populations, since it would imply new developments with every unit increase in population.

This necessitates the need to incorporate two secondary indicators that have been proposed, which use the same inputs as the core indicator i.e. built-up area per capita and total change in built up area.

Another limitation in the indicator is where zero or negative growth get reported, such as where population over the analysis period decreases or a natural disaster result in loss of the built-up area mass may lead to difficulties in interpreting the indicator and its meaning.

Difficulties in measuring the urban expansion by conurbations of two or more urban areas that are in close proximity; to which city/urban area do we attribute the urban growth and how to include it as one metric usually becomes a challenge.]

The method to compute ratio of land consumption rate to population growth rate follows five broad steps:

1. Deciding on the analysis period/years (between the twon censuses 2009 – 2019)
2. Delimitation of the urban area or city which will act as the geographical scope for the analysis (using DEGURBA level 30 classification)
3. Spatial analysis and computation of the land consumption rate
4. Spatial analysis and computation of the population growth rate
5. Computation of the ratio of land consumption rate to population growth rate
6. Computation of recommended secondary indicators]

*

Where: V_present is total built-up area in current year

V_past is total built-up area in past year

t is the number of years between V_present and V_past (or length in years of the period considered)

Population Growth rate i.e.

Where

LN is the natural logarithm value

Pop_t is the total population within the urban area/city in the past/initial year

Pop_t+n is the total population within the urban area/city in the current/final year

y is the number of years between the two measurement periods

Computation of the ratio of land consumption rate to population growth rate

The ratio of land consumption rate (LCRPGR) to population growth rate is calculated using the formula:

The overall formula can be summarized as:

Computation of recommended secondary indicators

There are two important secondary indicators which help interpret the value of the main indicator - LCRPGR, thus helping in better understanding the nature of urban growth in each urban area. Both indicators use the same input data as the LCRPGR and will thus not require additional work. These are:

1. Built-up area per capita – which is a measure of the average amount of built-up area available to each person in an urban area during each analysis year. This indicator can help identify when urban areas become too dense and/or when they become too sparsely populated. It is computed by dividing the total built-up area by the total urban population within the urban area/city at a given year, using the formula below:

Where

UrBU_t is the total built-up area/city in the urban area in time t (in square meters)

Pop_t is the population in the urban area in time t

1. Total change in built up area – which is a measure of the total increase in built up areas within the urban area over time. When applied to a small part of an urban area, such as the core city (or old part of the urban area), this indicator can be used to understand densification trends in urban areas. It is measured using the same inputs as the land consumption rate for the different analysis years, based on the below formula:

Where

UrBU_{t +n} is the total built-up area in the urban area/city in time the current/final year

UrBU_t is the total built-up area in the urban area/city in time the past/initial year

Data compiled is checked against several criteria including the data sources used, the application of internationally agreed definitions, classification and methodologies to the data from that source, etc. Once reviewed, appropriate feedback is then provided to stakeholders for further discussion.

https://data.unhabitat.org/datasets/template-for-compilation-of-sdg-indicator-11-3-1).]

1. Use of spatial data, gridded population data and City classification from the DEGURBA to undertake spatial analysis in terms of land consumption ratio.

2. The use of the National Sample of Cities Approach, which allows the selection of a representative sample of cities from where weighted national aggregates can be undertaken.

The guidance on implementation of the National Sample of Cities Approach is available here: https://unhabitat.org/sites/default/files/2020/06/national_sample_of_cities_english.pdf]

The Bureau being ISO 9001:2015 certified, has a quality management system in place that ensures that data produced meets the set international standards.]

The Bureau adheres to Kenya Statistical Quality Assurance Framework (KeSQAF) that ensures statistics produced meets the need of the users]

In adherence to the ISO 9001:2015 requirements the Bureau carries out its own internal audits based on KeSQAF Guidelines that ensures high quality statistics are produced.]

Data is available at KNBS and other state agencies such as the Kenya Space Agency (KSA) and Directorate of Resource Surveys and Remote Sensing]

Disaggregation Not Available

Significant variations between global and national figures are anticipated since locally produced built-up layers are used to compute the indicator.]

https://unhabitat.org/knowledge/data-and-analytics, https://www.urbanagendaplatform.org/learning, and https://data.unhabitat.org/.

https://unhabitat.org/sites/default/files/2020/06/national_sample_of_cities_english.pdf

https://unstats.un.org/unsd/statcom/51st-session/documents/BG-Item3j-Recommendation-E.pdf ]