QC Analytical Water Treatment/Distribution Conference

Transcription

1 QC Analytical Water Treatment/Distribution Conference May 23, 2016 QC Analytical Training Facility LeClaire, IA

2 by Brian Roth, P.E. Principal Civil Engineer Stanley Consultants, Inc. Muscatine, IA

3 Alice: Which road should I take? Cheshire Cat: That depends on where you are going. Alice: I don t know where I m going. Cheshire Cat: Then it doesn t matter which road you take! Adapted from Lewis Carroll, Through the Looking Glass, As Water Utility, do you feel like Alice?

4 Provides a framework for decision making to direct future short- and long-range development of the water system. Includes history, trends, projections and goals; Blueprint for the future (guides growth); Puts your utility decisions on Target!

5 What does this mean for you as a Water Utility? Master Planning Goals IMPROVE utilities capacity to predict flow and pressure DETERMINE system improvements needed to meet current and projected water demands and meet regulatory requirements. PRIORITIZE capital improvement projects that will sustain reliable water supply, treatment and distribution into the future. DELIVER high quality water to all customers

6 Audience Pole Questions What type of water system do you have? Municipal Industrial Institutional (college/university) Military

7 Audience Pole Questions What population size do you serve? Less than 1,000 Between 1,000 to 5,000 Between 5,000 to 10,000 More than 10,000

8 Audience Pole Questions How many pressure zones do you serve? One Two More than Two

9 Audience Pole Questions Who has a master plan within last 10 years? Yes No

10 Audience Pole Questions Who has water system issues that worry you? Yes No

11 Who needs to Master Plan? Every water system responsible for delivery of adequate & safe water to customers Addresses Demand/Supply Issues Addresses Treatment/Quality Issues Addresses Regulatory Compliance Addresses Aging Infrastructure

12 Why Plan At All? Required by Regulating Agencies Iowa DNR Construction Permit Preliminary Engineering Report (PER) i.e., Master Plan for major improvements or technical information justifying improvement for smaller projects Iowa State Revolving Fund (SRF) Requires PER

13 Why Plan At All? Financial Planning Rate setting (allows income to meet current and expected future system expenditures) Permits orderly growth Needed as responsible action by Water Utility to rate payers, utility boards and city councils Training, Transitions Communicates institutional knowledge When it is needed What type of training required

14 Why Plan At All? Operation and Maintenance Places emphasis on Preventive Maintenance instead of Reactive Maintenance/Repairs

15 Why Plan At All? It s the Right Thing to Do!

16 Vision Phase Information Gathering Phase Analysis and Decision-Making Phase Facility Master Plan and Capital Improvement Plan Phase

17 Vision Phase Define Goals (where do we want to be in 20 years?) Extent of service area Level of technology SCADA Meter Reading GIS Resource Allocation Funds Personnel Equipment

18 Vision Phase (cont.) Anticipate ways to meet expected regulation System Operations Maintain Status Quo Change in Direction New WTP? Sell/Buy water to/from another utility Water supply source

19 Collect Data Information Gathering Phase Previous reports, records, logs Pumping records Demand from meter/billing records Fire demand (from Insurance Services Office and/or fire department) Population data (trends, land us, projections) Water quality information including source and treated water Maintenance records/programs

20 Information Gathering Phase (cont.) Collect Data Facility condition reports including: Water mains, fire hydrants, valves, storage, wells, pumps, treatment, surface water intake Maps (pipe network, topographic) Pump curves Storage tank data (capacity, operating levels) IDNR, 10 State Standards, local rules, regulations and criteria Water treatment unit capacity, operating conditions, etc. Water supply capacity, sustainability, operating conditions, etc.

21 Analysis and Decision-Making Phase Water Use Projections Compile water billed from previous 5-10 years Compile water pumped from previous 5-10 years Determine Average day water use Maximum day water use Peak hour water use Results Project water use based on anticipated population growth Evaluate fire demands (location and amount) Identify top 10 or 15 water users Calculate unmetered/unbilled/unaccounted for water Data Entry

22 Analysis and Decision-Making Phase (cont.) Existing Facilities Pressure Zones Take into account service area, topography, desired pressure Storage Condition assessment (when last inspected, painted, cathodic protection, etc.) Establish how each is used (control pumps, effective capacity, turnover, etc.) High Service Pumps Number, capacity, duty and standby (determine firm capacity) How operated (sequencing, soft start/stop, manual/automatic control) Distribution System Pipe location, sizes (accurate mapping) Pipe age and material Maintenance programs (hydrant flushing, valve exercising) W.Q. issues (red water complaints) Maintenance issues (break history)

23 Analysis and Decision-Making Phase (cont.) Raw Water Sources Groundwater (number, depth, capacity, W.Q.) Maintenance issues (reduction in yield, etc.) Pump condition Water quality Reliability Surface Water Condition and maintenance of intake, pumps, etc. Water quality (seasonal variations) Maintenance issues Reliability

24 Analysis and Decision-Making Phase (cont.) Treatment Facilities Schematic flow diagram (processes, chemical addition) Condition and maintenance issues Redundancy/flexibility Operational control Type of chemicals and quantities Capacity (max day)

25 Analysis and Decision-Making Phase (cont.) Regulation Water supply/water quality Safe Drinking Water Act Lead & Copper Rule Total Coliform Rule Comprehensive Surface Water Treatment Rules Stage 1 Disinfectants & Disinfection Byproducts Rule Consumer Confidence Report Rule Stage 2 Disinfectants & Disinfection Byproducts Rule Long Term 2 Enhanced Surface Treatment Rule Ten State Standards Iowa Administrative Code & IDNR Guidelines Future Regulations

26 Analysis and Decision-Making Phase (cont.) Water Distribution Ten State Standards Pumps, storage, water mains, pressure Iowa DNR (Guidelines) Pumps, storage, water mains, pressure Insurance Services Office (ISO) Use recommended by Ten State Standards & Iowa DNR

27 Analysis and Decision-Making Phase (cont.) Water Supply & Treatment Evaluations Establish W.Q. target for finished water Determine capacity of supply and WTP unit processes Compare to design criteria from regulation (loading and W.Q.) Identify deficiencies Recommend improvements Develop cost Prioritize

28 Analysis and Decision-Making Phase (cont.) Water Distribution System The heart of a water distribution system analysis is a computer model of the network Software (model) selection is important first step Used to identify and make decisions on: Deficiencies (pipes, storage, pumps, pressure zone boundaries) Pipe sizing Pump operations Storage location & effectiveness

29 Analysis and Decision-Making Phase (cont.) Water Distribution System Enter all characteristics of network into model Pipes, pumps, storage, PRVs, demands, hydrants, operating conditions Analyze and evaluate water system performance for: Average day demand Maximum day demand Peak hour demand Fire demand Storage refilling Compare performance to design criteria from regulation/guidelines Identify deficiencies Recommend improvements Develop cost Prioritize

30 Capital Improvement Plan Phase Develop list of deficiencies Develop list of improvements to correct deficiencies Cost each improvement Prioritize Improvements Develop a timeline for implementation Summarize MASTER PLAN in final report (PER)

31 Typical Report Table of Content General Water Quality Water Demands Water Supply Water Treatment Water Storage Water Pumping Water Transmission/Distribution Cost Estimating Recommendations

32 Rule of Thumb Planning Horizon 20 Years

33 Rule of Thumb - Frequency Update Every 10 Years At major milestone events: New regulations Adding new demands Losing major water customer Major capital improvements

34 Rule of Thumb Average Day Demand Source Design Criteria General (default) 100 gpcpd Iowa Water Supply Facilities Design Standards 10 States Standards 100 gpcpd (>500 people) 80 gpcpd ( people) 60 gpcpd (<100 people) None

35 Rule of Thumb Maximum Day Demand Source Design Criteria General 2 x average day Iowa Water Supply Facilities Design Standards 10 States Standards 2 x average day (>500 people) 2.5 x average day (<500 people) None

36 Rule of Thumb Peak Hour Demand Source Design Criteria General Varies with water system Iowa Water Supply Facilities Design Standards 9.0 x average day (< 220 people) 7/P x average day (>220 people) Where P= population in 1,000s 7.0 for 1K 4.8 for 10K 3.2 for 100K 10 States Standards None

37 Rule of Thumb Fire Demand Source Insurance Services Office (ISO) (see Fire Suppression Rating Schedule for details) Design Criteria 3,500 gpm (Maximum Basic Fire Flow) Needed Fire Flow for specific buildings: Up to 2,500 gpm for 2 hrs. (300 K gal) 3,000-3,500 gpm for 3 hrs. (630 K gal) >3,500 gpm for 4 hrs. (840 K gal) Iowa Water Supply Facilities Design Standards 10 States Standards Use State ISO Recommendations Minimum: 500 gpm In accordance with State ISO Requirements

38 Rule of Thumb Maximum Day + Fire Demand Compare to peak hour Typically more demanding due to concentrate, localized water demands Assume elevated storage is near empty (end of fire)

39 Rule of Thumb Prioritization Flow Condition Current Future Average Day Priority 1 Priority 5 Maximum Day Priority 2 Priority 6 Peak Hour Priority 3 Priority 7 Max Day & Fire Priority 4 Priority 8 Prioritization sets the order of improvement implementation. Improvements needs to be designed to accommodate future peak hr/max day & fire flow conditions.

40 Rule of Thumb Unaccounted for Water Source Design Criteria General <10 percent Iowa Water Supply Facilities Design Standards 10 States Standards None None

41 Rule of Thumb Working Pressure Source General Design Criteria Normal range: psi Optimum: 60 psi Minimum during fire flow: 20 psi Iowa Water Supply Facilities Design Standards 10 States Standards Working pressure: 60 psi Minimum working pressure: 35 psi Minimum during fire flow: 20 psi Normal working pressure: psi Minimum working pressure: 35 psi Minimum pressure: 20 psi

42 Rule of Thumb Topography Effects Static HGL H1 = 120 ft System Pressure (PSI) = H (ft) x 0.43 (PSI/ft) Example: H1 = 120 ft H2 = 100 ft H1 120 ft x 0.43 (PSI/ft) 52 PSI H2 = 100 ft H2 100 ft x.43 (PSI/ft) 43 PSI 20 ft change in topography 9 PSI

43 Rule of Thumb Pipe Size Source General Design Criteria Absolute minimum: 4" Minimum serving hydrants: 6" Iowa Water Supply Facilities Design Standards 10 States Standards Absolute minimum: 2" Minimum serving hydrants: 6" Absolute minimum: None Minimum serving hydrants: 6"

44 Rule of Thumb System Pipe Velocity Average/Max Day limit to 2 ft/sec Fire limit to 5 ft/sec Higher velocities result in higher headlosses/lower system pressures Localized high velocities (ex. Pump Discharge) is ok Maximum 10 ft/sec

45 Rule of Thumb Friction Factor Estimates the system headlosses Varies by pipe material Varies by pipe age Typically includes minor headlosses for fittings/valves

46 Rule of Thumb Quick Pipe Capacity Comparison Pipe Flow = Pipe Area x Pipe Velocity Pipe Area = R² Pipe Dia (inch) Pipe Area ( Sq Ft ) Pipe Velocity Flow Rate (Ft/Sec) (Cu Ft/Sec) GPM 6 (3/12)² = (4/12)² = (6/12)² =

47 Rule of Thumb Supply Water quality is dependent upon the supply source Surface water typically more variable in water quality/temperature Well water typically harder in water quality Supply rate - firm capacity greater than Maximum day Requires redundant power supply Reclaimed water gaining in use/popularity

48 Rule of Thumb Treatment Water treatment is dependent upon the supply source/quality Treatment rate - firm capacity greater than Maximum Day Requires redundant power supply Membrane Treatment gaining in use/popularity, pretreatment requirements vary based on water source/quality

49 Rule of Thumb Storage Storage volume is dependent upon water demands and fire flows Storage volume is to simplify pumping/treatment requirements from peak hour to maximum day Elevated water storage can have water quality impacts Need to purposely let the tank fill/empty over typical day Can take advantages of off peak electrical rates

50 Rule of Thumb Storage Location Typically located away from pumping to reduce system headlosses Typically located on high ground to reduce tank height/construction costs HGL HGL Pump Station Flow Flow

51 Rule of Thumb Storage Volume Source Design Criteria General Per Procedures in " AWWA M32, Section 5 Iowa Water Supply Facilities Design Standards Effective storage = maximum day demand Minimum total storage = average day demand for systems not providing fire protection For systems providing fire protection, storage is larger of the following: Effective storage = average day demand or QfTf+0.8QiTf Qf = fire flow demand rate (gpm) Tf = fire flow duration (min.) Qi = instantaneous peak flow (gpm) (These values may be reduced if additional source, pumping, and emergency power is available)

52 Rule of Thumb Storage Volume (cont) Source Design Criteria 10 States Standards Minimum storage: average day demand (where no fire protection provided)

53 Rule of Thumb Pumping Pumping capacity is dependent upon the water storage type Pumping rate = firm capacity greater than Maximum Day with elevated water storage Pumping Capacity = firm capacity greater than Peak Hr without elevated water storage Requires redundant power supply

54 Rule of Thumb Pumping Source Design Criteria General Maximum day rate with largest pump out of service Iowa Water Supply Facilities Design Standards a) If adequate effective elevated storage is available, each ground storage facility is equipped with 2 service pumps each capable of pumping at maximum day rate. b) If effective storage is less than minimum required, high services pumping is determined as: HSP Capacity = Q P24 + (Q i Q P24 +Q f )(1-Actual Effective Elevated Storage/Storage per d)

55 Rule of Thumb Pumping (Cont) Source Iowa Water Supply Facilities Design Standards Design Criteria Where: HSP = High Service Pump Firm Capacity QP 24 = Maximum day demand rate (gpm) Qi = Instantaneous peak flow rate (gpm) Qf = Fire flow demand rate (gpm) Storage per Chap 7.1.3d: = QfTf x maximum day demand (gallons) when adequate emergency power is available and Tf = fire flow duration 10 States Standards Minimum of 2 pumping units providing maximum daily pumping demand with largest pump out of service

56 Rule of Thumb Hydrant Coverage Source Design Criteria General Spacing: 1 every 400 feet Iowa Water Supply Facilities Design Standards 10 States Standards None Spacing: at each street intersection and 1 every 350 to 600 feet depending on area served

57 Modeling Estimating water supply under various water demand conditions is difficult Water modeling provides tool to estimate system response Results need to make sense on a gut level

58 Rate Study Water master planning typically results in capital improvement projects Water system should be a self funding enterprise Rates need to cover capital improvement projects

59 CONCLUSION Don t ever be in Alice s position and have to ask, Which road should I take? Master Planning will make the direction clear and the road straight!

60 Thank you! For any questions or support, please contact Brian Roth