The effects of urban growth on downstream water resources. Mike Hutchins (CEH Wallingford) Steven Loiselle (Earthwatch Institute)

Transcription

1 The effects of urban growth on downstream water resources Mike Hutchins (CEH Wallingford) Steven Loiselle (Earthwatch Institute)

2 Community monitoring / citizen science Steven Loiselle

3 Citizen/Community Science and modelling/monitoring Why?... Lack of field data for monitoring, earth observation, model validation Active and knowledgeable communities supporting improved environmental management and policies

4 A network of citizen scientists acquiring water quality data in a consistent manner across the globe

5 Supporting modelling and management programmes of leading scientists and agencies in 30 locations

6 Obtaining robust and consistent water quality and ecological data External and automated quality control

7 Citizen scientist data in catchment scale monitoring High phytoplankton densities identified and reported Water colour low density (<14500 org/ml) high density (>14500 org/ml) Castilla et al. "Quantification of phytoplankton bloom dynamics by citizen scientists in urban and peri-urban environments." Environmental monitoring and assessment (2015).

8 Citizen scientist data in catchment scale monitoring Thames Water Blitz measurements on 16 September 2015 Site specific nitrate concentrations Thames Blitz 16/9/2015 (n= 645)

9 Citizen scientist data in catchment scale monitoring Thames Water Blitz measurements on 16 September 2015 Challenges of scale Water Blitz Basin averaged phosphate concentrations Thames Blitz 16/9/2015 Streams and rivers (n= 620, units = mg/l)

10 Continuous learning and engagement creating a virtual community

11 Is it worthwhile?... for the scientist and agency? Hours training CSLs Hours CSL sampling for the participants? 93% Committed to personal action 89% Improved understanding of water issues 92% Excellent research experience

12 How will water quality change by 2050? Previous modelling work shows that there will be an increase in the number of days per year having undesirable water quality Eutrophication is likely to become more prevalent and severe This assumes no change in population, which is estimated to increase by 16% to 2035 We are refining these estimates to consider future urbanisation (in POLLCURB project)

13 A NERC Changing Water Cycle project CEH-led: collaborators POLLCURB investigates how water pollution relates to change in urban areas, in particular brought about by population growth. By measuring land cover, river flow and quality in urbanising case studies (Bracknell/Swindon), and thereby by developing better models of how change in land cover affects water resources. Leads to. a better understanding of how urban areas affect our water resources so we can better plan future urban developments so they have less unwanted impacts on these resources

14 Increase in urban cover since 1960 Since 1960, increasing frequency/intensity of storm flows, especially in summer. Without 17 new balancing ponds and flood storage areas changes would have been 20% more severe in Bracknell. Aerial photography Topographic mapping (OS) Satellite imagery (5 images since 1975) Derivation of indices of the percentage of impervious surface cover.

15 Impact of winter storms in Swindon Ray at Water Eaton (84 km 2 ) Sub-catchments (% urban cover) 100 STW Pry Great Western Way Rodbourne Hayden Wick Water Eaton 1. Transient low DO in subcatchments a response to pollutant first flushes 2. Chronic low DO (and high ammonium) only seen at Water Eaton, not elsewhere 3. Summer DO sags are at least as severe as the winter storms 4. Winter DO in at Water Eaton was roughly 2 mg/l higher than winter

16 Diagnosing urban pollution: complex system Sources In-situ sediment Runoff: roads and paved areas Trading estates (poor waste control/storage) Misconnections in separate storm/foul sewer systems Sewage and household waste Contaminated land runoff Mechanisms Overflows: Combined sewers Storm tanks at sewage treatment works deliver untreated sewage First flushes of accumulated pollutants via surface sewers Treated effluents at sewage treatment works Leaky infrastructure Timing During/following heavy rainfall Rainfall following dry spells Continuous: especially important at low flow Continuous

17 Modelling activities for 2050s predictions Cellular automata land use change Local-scale testing Rainfall-runoff Urban water management QUESTOR model (daily time-step) Upstream QUESTOR boundary CEH weekly water quality ( ) Major urban areas outside London River channel water flow/quality Meta-model upscaling Tidal limit LONDON River Thames water resources Future urbanisation 20 km Future climate Basin-scale application

18 But the models can also be used for short-term forecasting A 6-month Follow-on Fund Pathfinder award for a scoping study (End: March 2016) 3 workpackages: objectives: WP1: enable us to define a business model WP2: define sensor technologies and a river monitoring network appropriate for professional scientists, community scientists and stakeholders WP3: identify model interface most appropriate for end-users to provide timely information on water quality Also a fully-costed proposal for a demonstration study

19 WP2: networks to support forecasting between Sites A Spectrum of sensors B C Low cost, mobile, ideal for surveys (e.g. depth, temp, cond) High cost, fixed, ideal for continuous monitoring using e.g. optical sensors Caversham (5) and Windsor (8) have continuous EA water quality and flow monitoring LONDON How much better can we forecast if we establish additional monitoring and 10 modelling of the main Thames and its tributary basins (A, B, C)? Tidal limit The Cut at Bracknell (C) is a POLLCURB case study Catchment based approach (CABA). We are exploring links to EA catchment partnerships in A (Loddon - via University 20 km of Reading) and B (South Chilterns - via FWR)

20 WP3: conceptual design of internet service platform 1. Sensors 2. Mobile Applications For the platform we have some expertise in CEH. We are looking for partners with IT expertise to fully cover the 4-stage process in the pilot study funding proposal 3. Data store 4. Analytics and visualisation

21 Challenges for analytics and visualisation - Costly to setup the model to run online - Successfully cater for a variety of information providers and information receivers Integrate diverse data from different domains Real time QUESTOR model applications Maps and charts of (i) data and (ii) forecast output

22 Water quality forecasting is needed! 1. By regulators (e.g. Environment Agency asked for information in June about the likely fate of this year s algal bloom, a problem ideally suited to our proposed system) 2. By recreational groups (e.g. anglers) 3. We want to investigate the views and potential benefits to the water industry (e.g. protection of water supply intakes?)

23 We are looking for partners for a full proposal 1. To act as end-users of the forecasting system 2. To act as advisors in formulating the business model 3. To be facilitators for establishing local networks inclusive of community participation Thank You