Escoamento Superficial: Vazão, Hidrógrafa, Inundações, Modelos hidrológicos

1. Escoamento Superficial: Vazão, Hidrógrafa, Inundações, Modelos hidrológicos

2. modified from www.usda.gov/stream_restoration/chap1.html Figure 1.18 • Q - Volume de água passando por um ponto por unidade de área • Q=VA ou WDV

3. www.aquatic.uoguelph.ca/rivers/chphys.htm Vazão e hidrógrafa

4. Hidrógrafa Anual

5. Hidrógrafa de evento Figure 1.14 www.usda.gov/stream_restoration/chap1.html

6. Figure 1.15 http://www.usda.gov/stream_restoration/Images/scrhimage/chap1/fig1-15.jpg Efeitos da urbanização em uma hidrógrafa de evento

7. Fig. - 2.10 www.usda.gov/stream_restoration/chap1.html Caminhos do escoamento superficial

8. Escoamento superficial • Ocorrem quando solos • Estão saturados (após pesada chuva) • Possuem baixa permeabilidade (ex. argila) • Fortemente influenciado pela paisagem e uso da terra • Região de exposição de rochas e base de lagos são impermeáveis ou tem baixa permeabilidade • Superfícies impermeáveis (estacionamentos) gera superfícies impermeáveis • Práticas de atividades florestais e agrícolas afetam o fluxo dos sistemas de drenagem

9. Características Físicas que Afetam o Escoamento • Declividade • Topografia • Direção de orientação • Padrão de drenagem • Presença de lagos, reservatórios • Uso da Terra • Vegetação • Tipo de Solo • Área de drenagem • Forma da bacia • Altitude

10. www.aquatic.uoguelph.ca/rivers/chphys.htm Inundações • Nós tendemos a ver inundações como eventos não previsíveis e desastrosos. De fato inundações podem ser previsíveis e são ocorrências necessárias. • Como a superfície impermeável afeta a probabilidade de inundações?

11. Intervalo de Recorrência • “1 em 100 anos de inundação” • = probabilidade de 0.01 ou 1% • Também referido como intervalo de recorrência • Definido como P = 1 / T, onde: • P = Probabilidade de Inundação • T = Intervalo de Recorrência

12. Influência humana sobre as inundações www.aquatic.uoguelph.ca/rivers/chphys.htm • Rápido escoamento em rios canalizados aumenta a frequencia de inundações e o pico na hidrógrafa em pontos a jusante

13. Associando Uso da Terra com a Qualidade da Água Menos Superfície Impermeável = Mais Água

14. Superfície Impermeável • Fornece uma superfície para acumulação de poluentes • Leva ao aumento dos poluentes via escoamento e inundação • Inibe a recarga dos aquíferos

15. Impactos das mudanças do uso da terra • Efeitos Hidrológicos • Ruptura do balanço natural da água • Aumento do pico de inundação • Aumento do escoamento superficial • Maior frequencia de inundações

16. www.mmsd.com/stormwaterweb/Volume1B.htm Escoamento superficial e desenvolvimento

17. The Importance of Spatial Patterns Surface hydrologists have recognized the importance of spatial patterns of runoff generation, particularly as driven by topography (e.g. TOPMODEL, SHE, InHM, POWER, ……) But numerical experiments suggest that even small rates of recharge to deeper layers can dramatically influence patterns of wetness

18. Bringing together these two communities by using a common geospatial data model http://www.crwr.utexas.edu/giswr GIS Water Resources CRWR GIS in Water Resources Consortium

19. ArcGIS HydroData Model Hydrology Hydrography Maidment, 2002

20. National Hydro Data Programshttp://www.crwr.utexas.edu/giswr/nhdconf/nationalhydro.html National Elevation Dataset (NED) National Hydrography Dataset (NHD) Elevation Derivatives for National Applications (EDNA) Watershed Boundary Dataset

21. Streams Drainage Areas Hydrography Channels Terrain Surfaces Rainfall Response Digital Orthophotos Thematic Layers supporting the Arc Hydro data model Michael Zeiler “Modeling Our World”

22. How do we combine these data? Digital Elevation Models Streams Watersheds Waterbodies Maidment, 2002

23. An integrated raster-vector database Maidment, 2002

24. Integrating Data Inventory using a Behavioral Model Relationships between objects linked by tracing path of water movement Maidment, 2002

25. Intrinsic Hydrologic Modeling • Dr Tarboton • DEM-based hydrologic modeling • USGS • Stream Stats • Mean annual flows and pollutant loads http://ststdmamrl.er.usgs.gov/streamstats/expert.htm

26. Dynamic Linked Library Can have Fortran subroutines in a DLL Muskingum flow routing Maidment, 2002

27. Independent Hydrologic Model VB progam reads and writes text files Maidment, 2002

28. Analysis, Modeling, Decision Making Arc Hydro Geodatabase Interfaces to Arc Hydro Data and Models Excel ArcGIS Relational Database (Access) Visual Basic Maidment, 2002

29. Three basic water problems • Too little water (Drought and water supply) • Too much water (Flooding) • Its dirty (Water Quality) Also have significant GIS effort on environmental issues related to water such as habitat assessment Maidment, 2002

30. 1996 Texas Drought • George W. Bush, (then Governor of Texas) asked: “Tell me how much water we have, how much water we’re using and how much water we need” • State water officials did not have adequate answers Maidment, 2002

31. Texas Water Planning • 1997 Texas Legislature passed Senate Bill 1 which provided for • State-wide geospatial data development (topography, hydrography, land use, soils and orthophotos) • Water planning in 14 regions rather than state-wide • Assessment of water availability for all water permits Maidment, 2002

32. Hydrologic Cataloging Units (HUCS) Hydrologic Unit Code = 12100203 Guadalupe Basin (4 HUC’s) • 2015 HUC’s cover continental US • average area ~ 1 county Maidment, 2002

33. Stream Gauge (14) Water Diversion (440) Water Availability in the Guadalupe Basin Estimate water availability at each legally permitted water diversion point based on “naturalized” flow at stream gages and the effects of other permitted diversions Maidment, 2002

34. Digital Elevation Model San Marcos basin National Elevation Dataset 30m x 30m cells 11,000,000 cells to cover San Marcos basin 70,000,000 cells to cover Guadalupe basin Maidment, 2002

35. Drainage Area Delineated from the Digital Elevation Model Arc Hydro attribute DrainArea Maidment, 2002

36. Ad Af Qd = Qf Estimating Naturalized Flow at Diversion Points Naturalized flow record at stream gage (50 years of monthly flows) Qf Af Qd Estimated flow record at diversion point Ad Maidment, 2002

37. Length Downstream Flow distance (D to F) = Length Downstream (D) – Length Downstream (F) Length Downstream (F) F D D Seepage losses F Arc Hydro attribute LengthDown Length Downstream (D) Maidment, 2002

38. Flood Hydrology and Hydraulics ArcView Input Data DEM ArcView Flood plain maps HEC-GeoHMS Hec-GeoRAS HEC-RAS Water surface profiles HEC-HMS Flood discharge Maidment, 2002

39. Stream Definition: Waller Creek Austin Watersheds with Streamsderived from Aerial Photographs Streamlines generated by the aerial photographs are not always continuous. Maidment, 2002

40. Information for Correcting Stream Network • DEM • Contours • Storm sewers • Orthophotos Maidment, 2002

41. Resulting Corrected Stream • Subsequent steps: • Verification of corrected streams by flood hydrologists. • Running “tracer” program to connect arcs. • Burning of streams into DEM. Maidment, 2002

42. Area to Stream Outlet Connectivity Maidment, 2002

43. Area to Sewer InletConnectivity Maidment, 2002

44. Area to Area Connectivity: SchematicLinks built using NextDownID Maidment, 2002

45. TIWSSTexas Integrated Water Simulation System WRAP Water Availability SWAT Water Quality Arc Hydro Geospatial and Temporal Data Modflow Groundwater HEC Models Flooding & Water Management Maidment, 2002

46. Flood Plain Mapping Maidment, 2002

47. Connecting HMS and RAS Maidment, 2002

48. Flood Hydrology and Hydraulics ArcView Input Data DEM ArcView Flood plain maps HEC-GeoHMS Hec-GeoRAS HEC-RAS Water surface profiles HEC-HMS Flood discharge Maidment, 2002

49. HEC-RAS: Background • River Analysis System model of the U.S. Army Corps of Engineers • Input = cross-section geometry and flow rates • Output = flood water elevations Cross-Section Schematic Maidment, 2002

50. Waller Creek Watersheds Network Channel Maidment, 2002