Modeliranje in ocena vplivov razpršenih ukrepov zadrževanja in ponikanja meteorne vode na odtok iz urbanega povodja

Radinja, Matej (author), Banovec, Primož (mentor), Comas Matas, Joaquim (comentor), Atanasova, Nataša (comentor)

Urbanizacija povzroči spremembe v naravnem hidrološkem krogu, ki se kažejo v manjši infiltraciji in evapotranspiraciji ter povečanem površinskem odtoku. Temu botruje spremenjena raba tal, saj so predhodno prepustne površine nadomeščene z neprepustnimi. Mešani kanalizacijski sistemi so dimenzionirani tako, da prevajajo sanitarno vodo in v omejenih količinah tudi padavinsko vodo do čistilne naprave. Med padavinskimi dogodki, ko je njihova prevodna sposobnost presežena, razbremenilniki odvajajo presežne količine vode v odvodnik. Cilj te naloge je vzpostavitev modela, s katerim bodo ocenjeni ukrepi razpršenega zadrževanja in ponikanja meteornih voda (ang. SUDS), ki so alternativna oz. dopolnjujoča rešitev tradicionalnim rešitvam, kot so podzemni zadrževalniki in kanaliziranje, ki naj bi preprečile prelivanje iz mešanega kanalizacijskega sistema v reko Onyar prek razbremenilnika ob trgu Plaça dels Països Catalans v Gironi, Španija. V skladu s pogoji v urbanem povodju, ki pokriva 2,7 km2, sem razvil pet scenarijev možnih ukrepov razpršenega zadrževanja, ki so zajemali infiltracijske kotanje, infiltracijske jarke, zelene strehe in njihove kombinacije. Najbolj učinkovit scenarij glede na kriterij zmanjšanja prelivanja na enoto implementiranega ukrepa je bila kombinacija infiltracijskih kotlin in jarkov. Po večkriterijski analizi, v kateri so bili scenariji ocenjeni tudi s kriteriji: stroški, dodane vrednosti, biotska raznovrstnost, se je scenarij, ki vključuje samo infiltracijske kotanje, izkazal kot najbolj ugoden. Ta scenarij v povprečju zmanjša razbremenjevanje za 45 %. Ugotovili smo, da lahko SUDS-i znatno zmanjšajo količino razbremenjevanja iz mešanega kanalizacijskega sistema, medtem ko nudijo dodatne koristi. Zato bi morali biti vključeni v bodoče aktivnosti, povezane z upravljanjem voda na urbanih območjih, tj. v načrtovanje urbanega odvodnjavanja.

• Language: Slovenian
• Keywords: trajnostni sistemi za odvajanje padavinskih voda z urbanih površin, razbremenilnik mešanega kanalizacijskega sistema, površinski odtok, ponikanje
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: FGG - Faculty of Civil and Geodetic Engineering
• Publisher: [M. Radinja]
• Year: 2017
• PID: 20.500.12556/RUL-91814
• UDC: 628.1.037:628.2(043.3)
• COBISS.SI-ID: 8065377
• Publication date in RUL: 20.04.2017

Secondary language

• Language: English
• Title: Modelling and evaluation of impacts of distributed retention and infiltration measures on urban runoff

Abstract

Urbanization leads to disrupted natural hydrological circle resulting in lower infiltration and evapotranspiration and higher surface runoff of precipitation. This is caused by changed land use, where previously pervious surfaces are replaced by impervious surfaces. Combined sewer systems (CSS) are designed to convey sanitary flow and a limited amount of stormwater to the WWTP. Combined sewer overflows (CSO) are employed to discharge the excess water into the recipient during rain events when CSS capacity is exceeded. The aim of this thesis is to develop a model to assess the implementation of SUDS as an alternative and as a complementary solution to conventional solutions such as underground storage tanks and rechanneling to prevent overflows from CSS into the river Onyar through the CSO object located at Plaça dels Països Catalans in Girona, Spain. In accordance with the conditions in the urban catchment which covers 2.7 km2, five scenarios were developed consisting of following measures: infiltration basins, infiltration trenches, green roofs and their combinations. The most efficient scenario in terms of overflow reduction per unit of implemented SUDS measure was the one including the combination of infiltration basins and infiltration trenches. According to the multi-criteria analysis (including evaluations for costs, amenity and biodiversity), the scenario including only infiltration basins was most favorable. This scenario reduces overflow in average by 45%. In conclusion, SUDS can significantly reduce CSOs while offering additional benefits. Therefore, they should be included in the strategies of urban water management, i.e. in the design of the urban drainage systems.

• Keywords: sustainable urban drainage systems, combined sewer overflow, runoff, infiltration