Multipurpose Reservoirs and Reservoir Systems David Rosenberg CEE 6490 – Integrated River Basin / Watershed Planning & Management

Learning Objectives Diagram multi-purpose operations for a single reservoir Describe rules of thumb for drawdown and refill of reservoirs in series Compare rules of thumb for reservoirs in series and in parallel Illustrate use of rules in real reservoir systems Integrate rules into reservoir simulation models 2 Mokelumne River Calaveras River Mokelumne and Calaveras Rivers, CA (Google Earth) CEE 6490

Multi-purpose Reservoir Operations Partition reservoir storage into “pools” Each pool has a separate purpose Release (or avoid releasing) water to reach the “guide curve” CEE 6490David Rosenberg 3 Dead/Inactive pool (no release) Buffer pool (min. in-stream flow releases) Conservation pool (release to meet water supply / hydropower delivery targets) Flood pool (release to empty, but don’t flood downstream areas) Surcharge pool (emergency spillway releases) Top of dam Guide Curve

Seasonal guide-curve CEE 6490David Rosenberg 4 1, Storage in thousand acre-feet Contours are preceding 60-day basin-mean precip. (% of normal annual precip.) Release all excess storage above line as rapidly as possible, subject to: –Do not exceed 50,000 cfs or maximum rate of inflow for flood event –Do not exceed 150,000 cfs at any time –Flows in a downstream damage reach do not exceed 180,000 cfs (HEC, 1976)

Example 1. How to consider guide-curve operation in SLOP? CEE 6490David Rosenberg 5 Review Google Sheet with worked example from prior classGoogle Sheet Break into teams of two Duplicate the Master worksheet Modify your copy to include guide-curve operation. The guide curve is at 190 units (60 units for flood protection). (You will also need to do this to complete ILO-4)

Compare Operations Objectives * Releases to achieve objective depend on spatial configuration CEE 6490David Rosenberg 6 Purpose Single ReservoirReservoir System Water Supply Keep reservoir full; avoid spills; meet demands Avoid system spills* Flood Control Keep reservoir empty; avoid damaging releases Avoid damaging releases* Energy Storage Keep reservoir full + high head Max. total energy stored at end of refill season* Hydropower Production Keep reservoir full; meet energy demands Max. value of energy production* Recreation - Pool Keep reservoir fullEqualize marginal rec. benefits of additional water

Rules of Thumb Rules differ for different –Water uses –Spatial configurations 7 inflow release/spill Reservoirs in Series: inflow release/spill inflow release/spill Reservoirs in Parallel: CEE 6490

Operations Rules for Reservoirs in Series 8 PurposeRefill PeriodDrawdown Period Water SupplyFill upper reservoirs first Empty lower reservoirs first Flood ControlFill upper reservoirs first Empty lower reservoirs first Energy StorageFill upper reservoirs first Empty lower reservoirs first Hydropower Production Maximize storage in reservoirs with greatest energy production potential RecreationEqualize marginal recreational improvement of additional storage among reservoirs CEE 6490

Operations Rules for Reservoirs in Parallel 9 PurposeRefill PeriodDrawdown Period Water SupplyEqualize probability of seasonal spill among reservoirs Equalize probability of emptying among reservoirs Flood ControlLeave more storage space in reservoirs subject to flooding NA Energy Storage Equalize expected value (EV) of seasonal energy spill among reservoirs For the last time-step, equalize EV of refill season energy spill among reservoirs Hydropower Production Maximize storage in reservoirs with greatest energy production potential RecreationEqualize marginal recreation improvement of additional storage among reservoirs

Example 2. Illustrations Break into groups of two Select a reservoir system (next slides) Describe system and recommend operations for the specified water use in the Google DocGoogle Doc

A. Porcupine and Hyrum Reservoirs on the Little Bear River, UT Operating for water supply in South Cache Valley CEE 6490David Rosenberg 11

B. Smith & Morehouse, Rockport, and Echo Reservoirs, Weber Basin Operating for water supply on the Gateway Canal CEE 6490David Rosenberg 12 UDWR (2008), Hi-ResHi-Res

C. Echo and Pineview Reservoirs, Weber Basin Operating for the Ogden Bird Refuge CEE 6490David Rosenberg 13 UDWR (2008), Hi-ResHi-Res

D. Pineview and Willard Bay Reservoirs, Weber Basin Operating for the Slaterville Diversion and Warren Canal CEE 6490David Rosenberg 14 UDWR (2008), Hi-ResHi-Res

E. Mountain Dell and Little Dell Reservoirs: water supply for SLC Goharian and Burian (2014), Hi-Res Hi-Res

F. Upper Stillwater, Currant Creek, and Strawberry Reservoirs, Bonneville Unit CEE 6490David Rosenberg 16 Operating for water supply at Utah Lake Central Utah Water Conservancy District, Hi-ResHi-Res

Application Feather-Yuba River System, California

2 parallel reservoirs 4.8 MAF storage (90% of mean annual flow) Drains 4,100 mi 2 within larger 27,000 mi 2 of Sacramento River Basin 3 rd Marysville reservoir authorized, but never built Flood protection, Water supply, Hydropower, Recreation, In-stream flows Feather and Yuba Rivers, CA (Rosenberg, 2003) 18

Feather and Yuba Rivers, CA Schematic David Rosenberg 19 CEE 6490

Feather and Yuba Rivers, CA Analysis Method 1.Build Reservoir Simulation Models –HEC-ResSim for flood operations Synthetic storms, various return periods, hourly time-step –HEC-5 for water supply, hydropower and in-stream flow requirements Period-of-record of inflows, monthly time-step 2.Specify performance objectives (more next slide) 3.Simulate project alternatives –Base case (existing) –Storage reallocations (raise and lower guide curves) –Re-operate for lower downstream flood flow requirements 4.Select preferable alternative(s) David Rosenberg 20 CEE 6490

Feather and Yuba Rivers, CA Performance Indicators Objective flow criteria met? At… –Oroville, New Bullard’s Bar –Yuba City, Marysville –Feather + Yuba Confluence, Nicolaus Expected Annual Flood Damage ($) –Simulate for likely events (little water) and unlikely events (lots of water) –Calculate damage for each event based on flows at downstream impact areas (HEC-FIA) –Weight by event likelihood and damage amount –Annualize to $ amount people pay every year Reliability, Vulnerability, and Resilience to meet water supply demand (%) David Rosenberg 21 CEE 6490

Expected Annual Damages for Oroville & New Bullard’s Bar Storage Reallocations

Expected Annual Damage for Reservoir Re-Operations Alternatives

Feather and Yuba Rivers, CA Conclusions Storage reallocations have small influence on EAD Lowering flow objective to 270,000 cfs at Feather-Yuba confluence is most promising re-operation alternative Up to 200 TAF storage in Oroville serves little additional flood protection purpose Oroville reallocations have greater EAD reduction benefit than New Bullard’s Bar reallocations EAD extremely sensitive to flow at Marysville, Natomas, and levee failure stage at Natomas Difficult to operate for Nicolaus (Rosenberg, 2003) David Rosenberg 24 CEE 6490

Integrating concepts into reservoir simulation models

Reservoir Simulation Modeling Data Requirements For WEAP, HEC-ResSim, HEC-5, Oasis, RiverWare, etc. Time-series of inflows Spatial configuration of inflows Routing between model nodes Reservoir locations and –Physical data: pool elevation-storage-area curves, evaporation and leak rates –Dam outlets: elevation-release capacity curves Operations –Zones: elevations –Release rules and prioritization in each zone 26CEE 6490

Reservoir Simulation Modeling Computational Requirements Time step Method to calculate change in storage –Finite difference –Modified Puls (level pool) –Are inflows, releases, etc. at beginning of time step or averaged over the time step? Routing –Simple (constant discharge-storage; velocity-based) –Muskingum (variable discharge-storage; attenuation) –Hydraulic (unsteady flows, variable storage; wave and out- of-bank flow) 27CEE 6490

Reservoir Simulation Modeling Performance Measures a.Delivery-reliability b.Firm yield c.Max (or min) reservoir storage level d.Max (or min) flows at a particular location e.Hydropower generated f.Costs of shortages g.Economic revenues from (b) or (e) h.Vulnerability i.Resiliency j.And many, many others 28CEE 6490

Conclusions Use zones (pools) to allocate water to different purposes within a single reservoir Simple rules of thumb for operating single-purpose reservoir systems depend on spatial configuration Simulation, optimization, or learning machine models used to determine or test rules in real applications Model type depends on system and operations purpose(s) Numerous performance indicators Joint reservoir operation often beneficial CEE 6490David Rosenberg 29

References Bower, B. T., Hufschmidt, M. M., and Reedy, W. W. (1966). "Operating procedures: their role in the design of water-resource systems by simulation analysis." Design of Water Resource Systems, A. Maass and e. al, eds., Harvard University Press, Hashimoto, T., Stedinger, J. R., and Loucks, D. P. (1982). "Reliability, Resiliency, and Vulnerability Criteria for Water Resource System Performance Evaluation." Water Resources Research, 18(1), Hirsch, R. M., Cohon, J. L., and ReVelle, C. S. (1977). "Gains from joint operation of multiple reservoir systems." Water Resources Research, 13(2), Labadie, J. W. (2004). "Optimal Operation of Multireservoir Systems: State-of-the-Art Review." Journal of Water Resources Planning and Management, 130(2), , Lund, J. R. (2000). "Derived power production and energy drawdown rules for reservoir." Journal of Water Resources Planning and Management-Asce, 126(2), , Lund, J. R., and Ferreira, I. (1996). "Operating Rule Optimization for Missouri River Reservoir System." Journal of Water Resources Planning and Management, 122(4), , CEE 6490David Rosenberg 30

References (cont.) Lund, J. R., and Guzman, J. (1999). "Derived Operating Rules for Reservoirs in Series or in Parallel." Journal of Water Resources Planning and Management, 125(3), , Palmer, R. N., Smith, J. A., Cohon, J. L., and ReVelle, C. S. (1982). "Reservoir management in Potomac River Basin." Journal of Water Resources Planning and Management, 108(1), Paredes, J., and Lund, J. R. (2006). "Refill and drawdown rules for parallel reservoirs: Quantity and quality." Water Resources Management, 20(3), , e51&pi= e51&pi=1 Rosenberg, D. E. (2003). "Simulating Cooperative Flood and Water Supply Operations for two Parallel Reservoirs on the Feather and Yuba Rivers, CA," Masters Thesis, University of California, Davis, Davis, California, Wurbs, R. A. (1993). "Reservoir System Simulation and Optimization Models." Water Resources Planning and Management, 119(4), , Yeh, W. W. G. (1985). "Reservoir Management and Operations Models: A State of the Art Review." Water Resources Research, 21(12), CEE 6490David Rosenberg 31