water supply and sewerage design
DESCRIPTION
TRANSCRIPT
Anthony FangKirsten RiceViv PitterRyan WilliamsJeremy Molayem
WATER SUPPLY AND SEWER SYSTEM
DESIGN
ZONE AREAS
A
Residential Area: 66.281 acres Population Density: 40 people/acre Population: 2652 people
Industrial Area: 3.2881 acres Population Density: 20 people/acre Population: 66 people
Commercial Area: 5.3375 acres Use: 10 hours per weekday
ZONE POPULATION
I. WATER SUPPLY SYSTEM
Residential Average consumption: 2.652 x 105 gpd Peak day consumption: 5.304 x 105 gpd Peak hour consumption: 1.608 x 106 gpd
Industrial Weekday consumption: 1.44 x 106 gal/day Peak hour consumption:1.8 x 105 gal/hr
Commercial Average flow rate: 17.5 gpm Peak day flow rate: 35 gpm
DEMAND
Fire flow is calculated based on the equation NFF=(Oi)(Ci)[1.0+(X+P)i]
Q = 5200 gpm (10 hour duration) = 3.124 x 106 gpd
Total flow for max day and Fire flowQ tota l = 2.38x106 + 3.124x106 = 5.50 x 106 gpd
FIRE FLOW
WATER DISTRIBUTION MAP WITH OUTFALLS
DISTRIBUTION LAYOUT
System B – Pumping station to major center of demand with an elevated storage tank between the supply and demand
Average Day = 1.7 mgd.Max Day = 1.7 mgd x 1.5 = 2.55 mgdPeak hour = 2.55 mgd x 1.5 = 3.83 mgdMax day + Fire flow = 5.5 mgd
DISTRIBUTION STORAGE
DISTRIBUTION STORAGE
Demand Rate Calculation Pumping Head
Average Day (1.7 mgd)
115 + (0.67 x 19) 128 ft
Max. Day. (2.55 mgd)
115 + (1.42 x 19) 142 ft
Max. Hour. (3.83 mgd)
115 + (3.0 x 19) 172 ft
Max day + fire = (5.5 mgd)
115 + (6.1 x 19) 231 ft
Total Length of Pipe ~ 19,000 feetPipe Material = ductile iron (C = 140)Diameter: 12-14 inWater Tower Head – 310 ftPump Head – 305 ft
Worst Case: Pump Failure Pressure low: 28.84 psi, high: 40.21 psi
PIPING SYSTEM INFORMATION
HP=QxH/(3960*n)
Q= 3606 GPMH=305ftn=65%
HP=427.28 500 HP pump needed. Two pumps (one standby)
PUMP DESIGN
Fire hydrants are to be located 300 feet apart on each street and 150 feet apart in high value zones.
FIRE HYDRANT LOCATIONS
II. SEWER SYSTEM
SEWER DESIGN
For Commercial and Residential 25 F.U. => 40 gpm x 3 (Restaurants) = 120 gpm 10 F.U. => 30 gpm x 2 (Offi ces) = 60 gpm Total = 180 gpm
For Industry = (3000gpm) x (70%) = 2100 gpm
For Residential = (Max Hourly Use) x 70% = Sewage Flow
SEWER DESIGN
Summary
SEWER DESIGN
Pipe Material PVCMin. Velocity 2 ft/sMax Velocity 10 ft/sRoughness (n) 0.015Min Ground Cover 6 ftPercentage Full 50%Min. Pipe Diameter 8 in.Max Pipe Diameter 50 inMax Velocity (Actual) 7.7 ft/sMax Depth 22 ft.
III. STORMWATER SYSTEM
STORM DATA
Duration, Min Intensity, In/Hr5 7
10 5.515 520 4.325 3.930 3.7535 3.540 3.3545 3.250 3.1555 3.12560 3.1
STORM SEWER DESIGN
Design Criteria Value (Minimum) Value (Maximum)
Flow Velocity 3 ft/s 15 ft/s
Slope 0.02% 10%
Depth of Cover 5 ft below surface N/A
Diameter 1 ft N/A
Roughness Coefficient N/A N = 0.013
Capacity* N/A ¾, 0.75
Horizontal Distance from Drinking Water Lines**
10 ft N/A
Vertical Distance from Utilities**
1 ft
Pipe Material PVC for Diameter les
*ratio of flow depth to full depth**from Haestad Methods, Stormwater Conveyance Modeling and DesignDesign Restrictions•Hydraulic Gradient Line should be below surface elevation at all times.•Curved Storm Sewers are unacceptable (maintenance problems)Depth of cover should be at least 5 ft in order to prevent crushing of pipes due to loads.
CONDUITS EXCEEDING DESIGN CAPACITY
CONDUITS OVERCAPACITY AT 21 INCHES
CONDUITS OVERCAPACITY AT 24 INCHES
CONDUITS OVERCAPACITY AT 27 INCHES
DESIGN SATISFIED, ALL CAPACITY < 0.75
DESIGN CRITERION: 3FPS < VELOCITY <15FPS
DESIGN CRITERION, 0.2% < SLOPE <10%
CONDUIT DIAMETER
CONDUIT FLOW
HYDRAULIC PROFILES
HYDRAULIC PROFILES
HYDRAULIC PROFILES
SUMMARY
Pipe Material PVC or Reinforced Concrete (D>1ft)Min. Velocity 3.72 fpsMax. Velocity 12.3 fpsRoughness n=0.013Min Ground Cover 5 ftMax Capacity 75% fullnessMin. Pipe Diameter 12 inchesMax. Pipe Diameter 27 inchesMax Depth 22 ft
Worst Case ScenarioPump Failure, distribution only from water tower
Water tower height 310 ft Pump head = 0 ft
Pressure High- 40.21 psi Low- 28.84 psi
DISTRIBUTION DESIGN (SCENARIO 1)
Water Tower Failure, supply only from pump Water tower head = 0 ft Pump head = 305 ft
Pressure High: 44.99 psi Low: 30.52 psi
DISTRIBUTION DESIGN (SCENARIO 2)
Best Case Elevated Storage Tank -310 ft Pumping Reservoir- Total head about 305 ft
Pressure- High- 45.89 psi Low- 33.01 psi
DISTRIBUTION DESIGN (SCENARIO 3)