WaterTech 2015 Total Loading Management Plan - An Integrated Watershed Management Approach. Lily Ma, The City of Calgary April, 2015

Transcription

1 WaterTech 2015 Total Loading Management Plan - An Integrated Watershed Management Approach Lily Ma, The City of Calgary April, 2015

2 Presentation Outline History of City of Calgary s TLMP and BRWQM TLMP as An Integrated Approach to Watershed Management TLMP- Evaluate Cumulative Effect on Watershed TLM Monitoring Program Build City-wide Model for Stormwater Management River Water Quality Assessment Strategies for Managing loadings Research

3 History of TLMP TLMP required through City s EPEA Approval 1995 Bow River Impact Study TLMP embedded in EPEA Approval TLMP Annual Report TLMP 5-Yr Update Report Total Loading Objective Revisit EPEA Approval Renewal

4 TLMP Objective TSS Total Phosphorus No Objective Ammonia Background of TLMP Effluent concentration limit established than an annual average Nitrogen BRIS indicated that phosphorus is the limiting nutrient controlling the growth of aquatic vegetation CBOD BRIS indicated that CBOD has a negligible effect on DO

5 Bow River Water Quality Processes Linkages Between Loading Parameters and Impacts Ammonia Healthy Aquatic Ecosystem CBOD Dissolved Oxygen TSS Nutrients Aquatic Vegetation Fish Habitat 5

6 Bow River Water Quality Processes Upstream Tributaries Stormwater WWTPs TSS CBOD Nutrients DO DO Periphyton Macrophyte Slide 6

7 TLMP An Integrated Approach to Watershed Management Stormwater Model River Hydraulic Model Bow River Water Quality Model Receiving Water Assessment Stormwater Management Total Loading Management Plan Watershed Management Water Quality Objectives to Manage Cumulative Effect 7

8 TLMP An Integrated Approach to Watershed Management Storm Planning Stormwater Model River Hydraulic Model Water for Life Stormwater Quantity and Quality Targets Design and Modeling Infrastructure Planning Operation and Maintenance Stormwater Monitoring Bow River Water Quality Model Receiving Water Assessment Total Loading Management Plan Water Quality Objectives to Manage Cumulative Effect South Saskatchewan River Regional Plan Bow River Phosphorus Management Plan Watershed Management Plans River Water Quality Studies Watershed Monitoring Strategy 8

9 BRWQM: Modeling Cumulative Effect to Watershed Slide 9

10 Approach to Assess Total Loading Objectives Define substances of concern Instream thresholds and frequency of compliances Develop scenarios Regression Analysis and iterative modeling runs to derive loading objective WWTP and Stormwater Infrastructure Planning Slide 10

11 City of Calgary Total Loading Objective Assessment Data-intensive Approach: Climate data: temperature, evaporation, wind, sunlight River hydrology: hydrometric stations, river geometry Rainfall: City rain gauges, Environment Canada airport rain gauge Stormwater system data: catchments, ponds, outfalls Land development: Land use, soil type, imperviousness, land development planning Field monitoring: Flow and water quality of wastewater effluent, stormwater runoff, and receiving water Aquatic vegetation Benthic invertebrates

12 Total Loading Management Monitoring Program Comprehensive strategy to assess Calgary s wastewater effluent and stormwater runoff with the ultimate goal in protecting Bow River aquatic health Supports the Approval to Operate for the City s wastewater system

13 Objectives of TLM Monitoring Program Support assessment of TLMP objectives Support stormwater and river modeling efforts Assess loadings from point and non-point sources Support the development of Stormwater Management Strategy Evaluate the effectiveness of stormwater BMPs and progress on Stormwater Management Strategy Slide 13

14 TLM Monitoring Sites Slide 14

15 Stormwater Model Development: City Wide Model 300+ sub-catchments More than 90 stormwater wet ponds/constructed wetlands included in the model so far 27 rain gauges to reflect spatial differences of precipitation

16 SWMM Model Development: 2 Steps Calibration for catchments with monitoring data Apply calibrated hydrological & water quality parameters to entire city Slide 16

17 Stormwater Model Development: Hydrological Response Units Concept Slide 17

18 Model Development: Hydrology Calibration Model is a simplified representation of real world Purpose of calibration: make the model reliable Model calibration curve fitting Real World Model Slide 18

19 Model Development: Hydrology Calibration Calculate areas of hydrologic response units (HRUs) in calibration catchments. Assign hydrological parameters to HRUs. Manning s coefficient on pervious land (N-Perv) Depth of depression storage on pervious area (Dstore- Perv) Suction head, conductivity, and initial deficit Area weight HRU specific values for pervious areas in each catchment. Adjust parameters based on model results iteratively. Slide 19

20 Stormwater Model Development: Water Quality Calibration Pollutant build-up and wash-off from land surface Pollutant removal in stormwater ponds Calibration based on HRUs Land use can be further delineated. Important to apply parameters obtained from calibration sites to city wide. 20

21 Stormwater Model Development: Groundwater Representation Limited information available to directly configure groundwater simulation Review groundwater monitoring database Calibrated groundwater parameters after infiltration parameters Improve the overall model results 21

22 SWMM to WASP Evaluation Impact to Aquatic Ecosystem HEC-RAS will consider all flows into the Bow and potentially be used for evaluating the stormwater flow results WASP-MG needs to know the loadings from different sources Upstream, tributaries, City of Calgary outfalls, WWTPs 4 approaches to estimate loadings from stormwater SWMM model based on build-up and wash-off SWMM model based on EMCs from different land uses SWMM modeled flow and monitored daily water quality loading SWMM modeled flow and flow-water quality loading regression Modeled loadings in the Bow support the evaluation of loading estimation from stormwater Refinement of calibration after running WASP-MG Slide 22

23 Dissolution River Water Quality Simulation Configure / Calibrate WASP-MG Transport info from HEC-RAS Meteorological data for water temperature and aquatic vegetation simulation Daily loadings from upstream of the Bow, stormwater runoff, tributaries, and WWTPs WASP model will simulate interactions between substances, DO, and aquatic vegetation Loading objectives will be developed based on results of the WASP model Detritus Nutrients CBOD Organic Decay Death Macrophyte Dissolved Oxygen Sediment Oxygen Demand Periphyton Photosynthesis and Respiration Reaereation Slide 23

24 Strategies for Managing Loadings - TSS Focus for TSS is stormwater. Stormwater quantity & quality targets, and best management practices/source control measures would be helpful for reducing TSS loading in stormwater. Stormwater quality retrofit projects would enhance stormwater quality in existing communities not serviced by stormwater retention ponds. Slide 24

25 Strategies for Managing Loadings - TP Focus for TP is wastewater. WWTP upgrades and improved wastewater treatment technology is effective in treating TP in wastewater. Stormwater quantity & quality targets, and best management practices/source control measures would be helpful for reducing TP loading in stormwater. Slide 25

26 Research River water quality research to improve understanding on nutrients and their impact on aquatic vegetation TSS and nutrient characterization and transport in stormwater ponds and constructed wetlands Local stormwater BMP performance database 26

27 Questions? Slide 27