Predictive Modelling to aid the Active Management of Bathing

Waters

Andrew WitherEnvironment Agency (UK)

Science Group

Why do me need predictions?

•The Public want to know about water quality

•The new directive will require this knowledge for implementation

•Compliance can be enhanced

In each bathing siteIn each bathing site• Posting of laboratory result sheetsPosting of laboratory result sheets

Directly to the beach attendantsDirectly to the beach attendants

• Posting of informative panelsPosting of informative panels

1- P

ublic

Info

rmat

ion

(Oth

er fo

rms

1- P

ublic

Info

rmat

ion

(Oth

er fo

rms

of p

rovi

ding

pub

lic in

form

atio

n)

of p

rovi

ding

pub

lic in

form

atio

n)

SMS serviceSMS service

Bathing Bathing sitessites ReservoirsReservoirs

Supplying Supplying and sewer and sewer systemssystems

Hydraulic Hydraulic ResourcesResources

EU ReportsEU Reports

New New PagePage

Algarve Algarve 20042004

Bathing Water Bathing Water ClassificationClassification

Annual Annual SynthesesSyntheses

Viv´a Praia Viv´a Praia CampaignCampaign

SYNTETHISED DATASYNTETHISED DATA

•Through an INTERNET site www.snirh.inag.ptThrough an INTERNET site www.snirh.inag.pt

1 -

Pub

lic In

form

atio

n 1

- P

ublic

Info

rmat

ion

(Nat

iona

l Web

site

)(N

atio

nal W

ebsi

te)

1- P

ublic

Info

rmat

ion

1- P

ublic

Info

rmat

ion

(Nat

iona

l Web

site

)(N

atio

nal W

ebsi

te)

NEW PAGENEW PAGE

Requirements

Article 6:to predict ……the anticipated nature, frequency andduration of expected short-term pollution.

Article 7:to take ….. timely and adequate managementmeasures .include information to the public and, if necessary, atemporary prohibition on bathing.

West Kirby Guideline Good GoodMeols Guideline Poor PoorMoreton Imperative Good GoodNew Brighton Guideline Poor PoorFormby Guideline Good GoodAinsdale Imperative Sufficient PoorSouthport Imperative Sufficient PoorSt Annes Imperative Sufficient PoorSt Annes North Imperative Sufficient PoorBlackpool South Imperative Sufficient PoorBlackpool Central Imperative Sufficient PoorBlackpool North Imperative Sufficient PoorBispham Guideline Good GoodCleveleys Guideline Sufficient PoorFleetwood Imperative Poor PoorHeysham Half Moon Bay Imperative Poor PoorMorecambe South Imperative Poor PoorMorecambe North Imperative Poor PoorBardsea Imperative Poor PoorAldingham Imperative Poor PoorNewbiggin Imperative Poor PoorWalney Biggar Bank Imperative Sufficient SufficientWalney Sandy Gap Imperative Sufficient PoorWalney West Shore Guideline Sufficient PoorRoan Head Imperative Poor PoorAskam-in-Furness Imperative Poor PoorHaverigg Poor Poor PoorSilecroft Imperative Sufficient PoorSeascale Imperative Poor PoorWindermere, Lakeside YMCA Imperative Excellent ExcellentWindermere, Millerground Landing Imperative Good GoodWindermere, Fellfoot Imperative Excellent ExcellentSt Bees Imperative Sufficient PoorAllonby South Imperative Poor PoorAllonby Imperative Poor PoorSilloth Imperative Sufficient PoorSkinburness Imperative Sufficient Poor

Scope and Limitations for Discounting Samples

• Samples taken during short-term pollution may be disregarded

• the number of samples disregarded .. may represent no more than 15% of the total number of samples

Choice of Model

• There are 566 bathing water in Great Britain alone.

• At most sites predictive modelling will have to be undertaken with little increase in budget.

• Models will be implemented by non- specialists

Asking the right question

• The modellers’ task is to produce the best tool using only data that is readily available.

• Provide a stochastic model relating bathing water quality to basic environmental parameters

Irvine beach: aerial view of River Irvine/Garnock, Ayrshire

Compliance point

Model development

• Simple correlation model for public information (Scotland)

• Development of correlation model for assessing sample discounting (England)

• Multiple regression model for forecasting with confidence limits (ICREW)

North West - St Anne’sNorth West - St Anne’s

Prediction PASS, Microb. PASS

78%

Prediction FAIL, Microb. PASS

7%Prediction PASS, Microb. FAIL

3%

Prediction FAIL, Microb. FAIL

12%

Classification change

satisfactory - good