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Best Practices narrative update

From: Jeremy Tandy <jeremy.tandy@gmail.com>
Date: Sat, 30 Jul 2016 00:42:17 +0000
Message-ID: <CADtUq_2zipFS6hE1W_dw-Nteot5+3p9zMNzZj7nCPGeDXHwehA@mail.gmail.com>
To: SDW WG Public List <public-sdw-wg@w3.org>, Linda van den Brink <l.vandenbrink@geonovum.nl>, Payam Barnaghi <p.barnaghi@surrey.ac.uk>

As part of the recent flurry of activity around the best practices
document, I have been trying to refine the urban flood response narrative
that we will use to provide context to our examples.

My main aim has been to make each “activity” far more modular, therefore
enabling a reader to identify with one of the Actors; Frederick, Florence,
Carole etc.

I’m intending that this will form an Appendix in the BP doc.

The current status of this section:

   - more work required; including adding further details from
   BP_Narrative_2 <https://www.w3.org/2015/spatial/wiki/BP_Narrative_2> ...
   the examples themselves need much more detail so that they will be useful
   to practitioners
   - need to clarify what is narrative (story) and what is technical example
   - need to add clear headings for each section
   - describe each of the Actors upfront (?) along with a quick summary of
   their task/activity to help readers find things that are relevant

This already has a lot of words in it; I think we also need to find a way
to ‘compress’ the sprawl … perhaps using some javascript magic like Frans
et al did in the UC document.

So- even though there’s much work left to do, I wanted to share this with
you all today. Unfortunately, I’ve run out of time to work on this … and am
headed for vacation tomorrow, returning 15-August.

In the mean time, maybe one of my fellow editors can insert this (more or
less verbatim) in to the BP doc draft as a new Appendix … or share it as a
Google Doc (or similar) if folks want to do some collaborative editing.

Best Regards, Jeremy

(“see” you all in two weeks)


Note: Names and places used in this scenario are fictional, procedures and
practices may not reflect those used in the real world. Our intent is to
provide a coherent context within which the best practices can be
illustrated. We <strong>do not</strong> attempt to provide best practice
for management of flooding events. However, many of the procedures
discussed are based on information from [

Nieuwhaven is a flourishing coastal city in the Netherlands. In common with
much of the Netherlands, the low lying nature of Nieuwhaven make it prone
to flooding from both rivers and the North Sea. To mitigate or reduce risks
to homes and businesses, significant investment has been made to flood
control and water management infrastructure.

Flood Risk Management and Water Management are integrated in the
Netherlands. By combining [responsibilities for] daily water management and
flood risk management, the same people are involved who have a detailed
knowledge of their water systems and flood defences.

[image: multi-layer-safety-for-flood-risk-management.png]

[source: §2.3 “Multi-layer safety” for Flood Risk Management,

Flood risk management can be separated into three layers:

(3) Flood alerts, evacuation, response and recovery (civil protection
issues); both organisational and physical measures (e.g. identifying,
checking, repairing and signalling evacuation routes).

(2) Spatial planning issues; reducing the impact of flooding through
planning measures.

(1) Flood protection; constructing flood defences to reduce the probability
[of inundation and the impact of flooding]

Our scenario concentrates of element (3).

The Nieuwhaven Water Board (regional water management authority) is the
independent local government body responsible for maintaining the system of
dikes, drainage, canals and pumping stations that are designed to keep the
city and surrounding environment from flooding.

> typical SDI approach?

> include designated “flood zone” features, waterbody features, dikes and
control infrastructure etc.

Based on assessment of historical flooding events, Newhaven Water Board is
able to determine the extent of flooding that would occur as the result of
hypothetical storm surge and river flooding events.

> inundation extent from hypothetical scenarios

> vector geometries for the inundation extent based on assessment against
high-resolution DEM (Digital Elevation Model) / DTM (Digital Terrain Model)
derived from photogrammetry & lidar

> API enables users to define the geometry resolution (from 1m resolution
up to 50m?) they need for their application using a query parameter [e.g.
to manage the volume of complex geometries]

Frederick …

Municipal emergency services, public health authorities and water boards
are grouped according to a “safety region” in order to establish a
multi-disciplinary “emergency team” for crisis management. This helps to
ensure that there is effective communication between those responsible for
public safety and those responsible for flood control and water management.

Each safety region prepares systematically for its own specific
characteristics, based on available capabilities. This plan, the “Flood
Response Plan”, includes evacuation strategies that are developed in
response to hypothetical flooding events. Scenarios are prepared beforehand
and carefully considered. The emergency team must be prepared at all times
to deliver an assessment on a disaster / incident scenario and advise on
proposed interventions, e.g. evacuation and deployment of temporary flood

The numbers of citizens impacted by each hypothetical flooding event are
determined by cross-referencing the areas affected by surface water
flooding with census data.

Statistics Netherlands <https://www.cbs.nl/en-gb/about-us/organisation>
(CBS) publishes reliable and coherent statistical information which respond
to the needs of Dutch society and is responsible for compiling official
national statistics.

> Does CBS provide city-level census data?

CBS makes use of OData, the Open Data Protocol v4, to provide open datasets
for use by third parties. Furthermore, CBS provides a search interface to
help a user find the dataset of interest [or is this supported through
discovery via the common search engines]

[CSV is another option]

CBS also provides metadata for the census dataset, in both human- and
machine-readable forms.

A download of all the data may leave the data user with a large amount of
information to work with, when they are only interested in the subset of
areas affected by flooding. Therefore it is desirable that the publisher
makes the data available via an API, where the user can select the area of
interest and retrieve relevant information, possibly also narrowing down
their choice by other statistical dimensions.

Census data naturally takes the form of a statistical 'data cube', with
statistical dimensions of area, time, gender, age range etc. A useful
standards-based approach to making the data available would be to represent
it as RDF, using the RDF Data Cube Vocabulary [VOCAB-DATA-CUBE
<https://www.w3.org/TR/vocab-data-cube/>]. This offers a standards based
way to represent statistical data and associated metadata as RDF. API
access to the data could be provided via a SPARQL endpoint, or a more
specific API. The Linked Data API, implemented by Epimorphics’ ELDA,
provides a useful mechanism to expose simple RESTful APIs on top of

Florence …

Population data from a census is typically broken down by area, gender, age
(and perhaps other statistical dimensions) and relates to a particular time.

CBS uses established URLs to identify each each administrative area for
which population data is available. Details of the administrative areas for
Nieuwhaven are published by the municipal government. This information
includes the geometry for each administrative area.

Data about administrative areas are often useful - perhaps they represent
one of the most popular spatial datasets. In this case they are useful for
coordinating the emergency response, i.e. predicting and tracking which
neighbourhoods or districts are threatened. Because the names of local
administrative areas such as neighbourhoods are very well known they are
also useful for communication with citizens, i.e. letting them know if
their neighbourhood is threatened by the flood or not.

Because the administrative area datasets is quite popular, all kinds of
data users will want to use it - not only GIS experts. To enable them to
find the data on the web, it was published in such a way that search
engines can crawl the data, making the data findable using popular search

> publish administrative areas with geometry

> geometries published with national CRS via SDI (this could be converted
in the browser using proj4.js)

Carole …

By cross-referencing the population statistics, administrative areas and
surface water flooding extent (e.g. by calculating the intersection of the
flood with administrative areas), the number of citizens impacted by each
hypothetical flooding event can be estimated.

Once the number of citizens that need refuge has been determined, the
emergency teams can designate public buildings, such as schools and sports
centres, as evacuation points and define safe transit routes to get to
those points.

The municipal government published details of the built infrastructure
within Nieuwhaven, including public buildings and transport infrastructure.

> each feature is uniquely identified

> each feature is indexed by search engines

> dataset is published as vector tile-set (like OSM)

The municipal government also publishes metadata describing each dataset
(DWBP-BP1) that, besides free text descriptions (e.g., title, abstract),
include the following information:

   - the type of objects/features described - e.g., with a thematic
   classification (DWBP-BP2)
   - spatial coverage / temporal coverage - to identify if data match the
   area of interest
   - coordinate reference system(s) used - to correctly interpret geometries
   - spatial resolution - to identify data with the right level of detail
   - distribution format(s) and API to get access to the data (at a
   different level of granularity) - to identify those datasets consumable by
   the intended application(s) (DWBP-BP4, DWBP-BP13)
   - date of last modification - to see whether data are up to date
   - the parties responsible for the creation and maintenance of the data -
   to verify data authoritativeness (DWBP-BP6)

To facilitate data discoverability, metadata should be published via
<http://schema.org> different channels and formats (DWBP-BP22). Typically,
such metadata are maintained in geospatial catalogues, encoded based on ISO
19115 <https://en.wikipedia.org/wiki/Geospatial_metadata> - the standard
for geospatial metadata. In addition to this, such metadata can be served
in RDF, and made queryable via a SPARQL endpoint; e.g. GeoDCAT-AP
<https://joinup.ec.europa.eu/node/139283/> provides an XSLT-based mechanism
to automatically transform ISO 19115 metadata into RDF, following a schema
based on the W3C Data Catalog Vocabulary (DCAT).

This solution can be further enhanced by making data discoverable and
indexable via search engines. The advantage is that this would allow data
consumers to discover the data even though they do not know the relevant
catalogue(s), and to find alternative data sources.

This can be achieved, following Search Engine Optimisation (SEO)
techniques, by embedding metadata in catalogue’s Web pages, with mechanisms
like HTML-RDFa, Microdata, and Microformats. Examples of this approach
include the following ones:

   - In the Geonovum testbed <https://geo4web-testbed.github.io/topic4/>,
   dataset pages from a geospatial catalogue embed metadata, represented by
   using the Schema.org <http://schema.org> vocabulary, directly generated
   from the relevant ISO 19115 records.
   - The experimental GeoDCAT-AP API
   allows data publishers to serve ISO 19115 records in different RDF
   serialisation formats, including HTML+RDFa, on top of a geospatial
   catalogue and/or an OGC Catalog Service for the Web (CSW).

> publish dataset metadata

Lorenzo …

Temporary flood defences are common where roads and railways cross
permanent flood defences or are built up on boulevards along rivers. Also,
temporary flood defences are also deployed where dikes have not passed
their annual visual inspection or 5-yearly assessment. Information
regarding the condition of dikes cannot be incorporated into the plan, and
must be considered during an actual flood event.

> individual transport network segments and flood defence features are
uniquely identified

> spatial relations are used to define where transport infrastructure cross
flood defences, and hence quickly determine where to deploy temporary flood
defences without the need for detailed spatial analysis … this can be used
to demonstrate 3rd-party linking; e.g. the spatial relations are published
by an organisation that owns nether of the target datasets

> locations for temporary flood defences are provided to the relevant
emergency services teams

James …

Storm surge and river flood warning services are provided by the National
Water Management Centre (WMCN) at Rijkswaterstaat
<https://www.rijkswaterstaat.nl/>, who are responsible for the design,
construction, management and maintenance of the main infrastructure
facilities in the Netherlands such as the main road network, the main
waterway network and water systems.

The storm surge warning service is triggered by storm surge alert from the
Royal Netherlands Meteorological Institute (KNMI), the Dutch national
weather service. A forecast combination of heavy rainfall, high-tide and
storm makes it likely that a flooding will occur in the next 120 hours.
Specialists use meteorological, hydrological and urban flood prediction
models within the Flood Early Warning System (FEWS) to estimate peak
water-levels, when these will occur and which area will likely be flooded.

> Note. “Flood Early Warning System” is the name of a system provided by
Deltares; is it sufficiently generic or should we avoid this terminology?

The Storm surge warnings consist of predicted maximum water levels and a
general description of wind and tide. 10-minute water level forecasts are
computed and distributed, including details of wave run-up and overtopping
for dikes.

Every 6 hours, new meteorological predications are incorporated into the
flood prediction, resulting in a new version of the 10-minute water level
forecast dataset being made available.

> landing page (with descriptive metadata) for each forecast dataset

> entire forecast dataset available in a number of (compact binary) formats
for offline use (e.g. NetCDF, HDF5)

> ”current" forecast uniquely identified

> exposed via a self-describing restful API; subdivided by time (each
time-step listed in metadata)

> use RDF Data Cube to describe the dataset structure

> whole time-slice available as covjson

> simple point data extraction (in WGS84 coordinates); covjson point
feature with water depth time series

> simple bbox extraction (in WGS84 coordinates); covjson

> use covjson data to illustrate (1) depth of flooding, (2) changes in
inundation through time

Felix …

The emergency team for the Nieuwhaven safety region compare the predictions
for the forecast flooding event against the hypothetical scenarios
developed in the Flood Response <http://www.crisis.nl> Plan to determine
which of the prepared response plans to execute.

Based on this assessment, the imminent flooding event requires a number of
temporary flood defences to be deployed and evacuation of some districts of

The emergency team identify where additional temporary flood defences are
required due to any dikes that are in a state of disrepair (e.g. having
failed their annual or 5-yearly assessments).

> cross reference the location of each damaged dike with predicted
high-water level, determined via an API call into the 10-minute water level
forecasts to extract a water level time-series for a given point to
determine if the water level is predicted to exceed a threshold, in which
case, temporary flood defences will be required.

Details of the emergency and the evacuation plan must be communicated to
citizens. They are kept informed during and prior to the event using
multiple channels:

   - local radio and television networks
   - news and medi <http://schema.org>a agencies; television, radio
and >>> on-line
   - official national Government website www.crisis.nl, including
specific information
   about flooding events
   - cell broadcasting via the Government’s NL-Alert
   <http://www.crisis.nl/nl-alert> system, providing SMS message alerts to
   all mobile phones in the vicinity of a life a <http://schema.org/Place>nd
   health threatening emergency
   - air raid sirens

The evacuation plan must be discoverable by the public. The intent is for
each plan to be both human (primarily) and machine readable. The
requirement for machine readability is mostly to support automated
discovery of the content via web search. The URL itself ideally should also
be "human friendly" as it should be easy to share verbally in addition to
being embedded and linked to from other web pages.

While making the plan <http://schema.org>s clear and understandable to
human readers is well understood (and beyond the scope of this best
practices document!). The challenge is to make the content machine
readable. The use of a simple tag based schema using microdata, RDFa or
JSON-LD is recommended. A simple first step might be to use the schema.org
"Event" item tag <div class="event-wrapper" itemscope itemtype="
http://schema.org/Event">, which has useful generic properties of date,
location, duration etc. The places of evacuation refuges (e.g. schools,
sports centres etc) should be tagged using the generic “

> publish simple, authoritative Web pages that describe the evacuation
plans; include structured mark-up to help search engines index the rich
content; each evacuation plan must be uniquely identified

> the evacuation plans link to the <a>spatial things</a> (e.g. schools,
sports centres, administrative areas etc.) designated as refuges etc.

Details of the evacuation route should be provided ideally as a textual
description (perhaps machine readable using the schema.org "TravelAction
<https://schema.org/TravelAction>" item, although this is rather limited)
and a graphical representation. Potentially route information could be
encoded using a format such as OpenLR <http://www.openlr.org/index.html>
but this has not achieved widespread adoption.

> describe transit routes

Bryan …

News and media agencies provide Web applications that help communicate the
evacuation to citizens as effectively as possible; e.g. by creating simple
Web applications that direct one to the correct evacuation plan based on
their postal code or online mapping tools. media agencies may
cross-reference evacuation plans with Features that have non-official
identifiers; e.g. from What3Words (W3W) or GeoNames.

> simple App to help people determine if they will be flooded ... simple
lookup based on postcode area; x-ref postcode area with predicted surface
water extent (from forecast dataset) via spatial analysis of geometries;
use API into forecast dataset to extract water-level time series for a
given location

Vernon …

During a flood event, the Flood Response Plan indicates that emergency
services will have to focus their efforts on reducing the number of
fatalities. This means that if an evacuation order is given, the efforts of
the emergency services will be focused on traffic control and on non self
reliant groups.

As the flood event progresses, the emergency services provide evacuation
assistance for the vulnerable, such as the residents of care homes.

The municipal public health authority publishes details of care homes and
other health care facilities on-line as open data, using a simple CSV

> CSV formatted spatial data … either using well-known-text encoded
geometry_or_ providing an address that can be geocoded? … It is important
that the structure and meaning of the data is documented, by providing a
definition for each column header and information on the type of data to be
expected in the cells. This should follow the approach defined in the W3C
Metadata Vocabulary for [TABULAR-METADATA

Jan …

The position of each vehicle used by the emergency services is tracked in
near real-time using GPS. The coordinators within the emergency team are
able to view both current position and where the vehicles have been;
gauging the evacuation progress against the Flood Response Plan.

> moving features; where “geometry” changes with time

Ricardo …

During floods and storm surges, professionals (often aided by trained
volunteers) constantly monitor all flood defences. Measurements include:
water level, wave height, wind speed and direction.

The emergency team use these observations to monitor the rising water
levels to ensure that these are consistent with the predictions (both in
terms of timing and peak water-level) in case additional interventions,
such as evacuating more districts, are required.

A real-time data stream of water level at a specific location within
Nieuwhaven’s canals is published from an automated monitoring system
operated by the Water Board; e.g. a Web-enabled sensor.

> metadata about the data stream enabling discovery and interpretation of
the data stream values; e.g. what quantity kind is being measured with
which units of measurement, what is the sensor etc.

> relate the sensor (and the data-stream it provides) to the water body
whose water level it is intended to monitor

> describe the sensor location

> SensorThings API example; what about use of protocols other than HTTP;
e.g. MQTT?

Megan …

Fortunately, the prediction is sufficiently accurate that the evacuation
plan remains effe
<https://twitter.com/leoniemellor/status/738884030511222785>ctive. However,
the emergency team notice that the water level in one particular sector is
higher than predicted- and rising. Further analysis indicates that an
automated control gate has malfunctioned.

A team is dispatched to use the manual override. The manual control is
located using relative positioning.

> the manual override / control is located using relative positioning

Tomas …

During the flood, citizens themselves become engaged with the flood event;
they use social media to post geo-tagged messages regarding their
observations of the flood (“the #flood has reached my home” or “Mount
Pleasant Road closed at junction with Acacia Avenue #flood”, perhaps
accompanied by photographs) or offer localised help (“come charge your
phone at my porch #floodresponse”).

The aggregated social media messages are used by the emergency team to
complement the monitoring data provided by the Water Board, tracking the
progress of the flooding event in near real-time.

> social media, water extent … VGI …
https://twitter.com/leoniemellor/status/738884030511222785 … aggregated
social media posts; situational awareness … how to reconcile place names
with resources formally identified with URLs? … especially where local or
informal place names (with ‘fuzzy’ boundaries) are used (e.g. “north of

> … ambiguity: “#flooding the water is 2 feet deep at my house”

> … social media platform providers drive collection of particular
information from users of the platform

> … or volunteers might blog, creating content in HTML using a publishing

> geotagging photos of flood extent ... using EXIF data from photos ...
provide an API to search that resource [Instagram] ... emergency responders
use this to track the progress of the flood against prediction

Ron, Heather, Charles …

Due to the prioritisation of emergency services elsewhere, the Flood
Response Plan assumes that the general public will have to be self reliant
or resilient for a number of days.

Using social media, local businesses offer services to those affected by
the flood; for example, a local bakery offers food and water and asks for
help to move these supplies to the evacuation refuge nearby.

> #floodresponse ... messages are geotagged (location label) but also use
HTTP URI to precisely identify the location (e.g. from W3W)

Susan and Patrick …


(image/pjpeg attachment: Image-1.jpg)

(image/png attachment: multi-layer-safety-for-flood-risk-management.png)

Received on Saturday, 30 July 2016 00:43:03 UTC

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