TY - JOUR

T1 - To what extent does variability of historical rainfall series influence extreme event statistics of sewer system surcharge and overflows?

A1 - Schaarup-Jensen,Kjeld

A1 - Rasmussen,Michael R.

A1 - Thorndahl,Søren

AU - Schaarup-Jensen,Kjeld

AU - Rasmussen,Michael R.

AU - Thorndahl,Søren

PB - I W A Publishing

PY - 2009

Y1 - 2009

N2 - In urban drainage modelling long term extreme statistics has become an important basis for decision-making e.g. in connection with renovation projects. Therefore it is of great importance to minimize the uncertainties concerning long term prediction of maximum water levels and combined sewer overflow (CSO) in drainage systems. These uncertainties originate from large uncertainties regarding rainfall inputs, parameters, and assessment of return periods. This paper investigates how the choice of rainfall time series influences the extreme events statistics of max water levels in manholes and CSO volumes. Traditionally it is rarely to dispose of long term rainfall time series from a local catchment rain gauge. In the present case study this is actually the case. 2 rainfall gauges have recorded events for approximately 9 years at 2 locations within the catchment. Beside these 2 gauges another 7 gauges are located at a distance of max 20 kilometers from the catchment. All gauges are included in the Danish national rain gauge system which was launched in 1976. The paper describes to what extent the extreme events statistics based on these 9 series diverge from each other and how this diversity can be handled. All simulations are performed by means of the MOUSE LTS model.

AB - In urban drainage modelling long term extreme statistics has become an important basis for decision-making e.g. in connection with renovation projects. Therefore it is of great importance to minimize the uncertainties concerning long term prediction of maximum water levels and combined sewer overflow (CSO) in drainage systems. These uncertainties originate from large uncertainties regarding rainfall inputs, parameters, and assessment of return periods. This paper investigates how the choice of rainfall time series influences the extreme events statistics of max water levels in manholes and CSO volumes. Traditionally it is rarely to dispose of long term rainfall time series from a local catchment rain gauge. In the present case study this is actually the case. 2 rainfall gauges have recorded events for approximately 9 years at 2 locations within the catchment. Beside these 2 gauges another 7 gauges are located at a distance of max 20 kilometers from the catchment. All gauges are included in the Danish national rain gauge system which was launched in 1976. The paper describes to what extent the extreme events statistics based on these 9 series diverge from each other and how this diversity can be handled. All simulations are performed by means of the MOUSE LTS model.

KW - Historical rainfall series

KW - MOUSE LTS

KW - Sewer system surcharge

KW - CSO volumes

KW - Extreme events statistics

U2 - 10.2166/wst.2009.290

DO - 10.2166/wst.2009.290

JO - Water Science and Technology

JF - Water Science and Technology

SN - 0273-1223

IS - 1

VL - 60

SP - 87

EP - 95

ER -