Gateway BP (1.1)-CS 900212 (2)DONALD E. DAVIS
CONSULTING ENGINEERS
5506 COCKRELL HILL ROAD
DALLAS, TEXAS 7523~
(214) 337-2332
FEB. 12, 1990
CO190022.AHP
DESI~ DATA
THE FACTORS USED IN DESIGN METHOD 1 ARE:
RESIDENTIAL USES:
S UNITS PER ACRE
3.5 PERSONS PER UNIT
100 GALLONS PER DAY PER PERSON
COMMERCIAL USES:
25% BUILDING TO LAND RATIO
I PERSON PER 100 SQ. FEET
100 GALLONS PER DAY PER PERSON
INDUSTRIAL AND OFFICE USES:
33% BUILDING TO LAND RATIO
1 PERSON PER 330 SQ. FEET
100 GALLONS PER DAY PER PERSON
A THIRD METHOD BASED ON FIXTURE UNITS WAS INVESTIGATED.
INDICATION OF THE RESULTS WERE VERY CLOSE TO METHOD NUMBER
METHOD WAS THEREFORE CONSIDERED TO BE UNNECESSARY.
THE PRELIMINARY
ONE. THIS THIRD
THERE ARE 3 PUMPS AT THE OUTFALL OF THIS SANITARY SEWER WITH A CAPACITY OF 15
M.G.D.. A STUDY SHOULD BE MADE TO DETERMINE IF OTHER AREAS ARE TO BE PUMPED
THROUGH THIS STATION AND IF THE PUMPS AND OTHER FACILITIES ARE ADEQUATE FOR
THE FUTURE DEVELOPMENT.
GATEWAY BUSINESS PARK
WATER AND WASTEWATER DEMAND ANALYSIS
II.
POPULATION FORECAST FOR LIGHT INDUSTRIAL LAND USE
A. Assumptions
2.
3.
4.
85% of gross land area is developable land.
50% of developable land is gross floor space.
50% of gross floor space is office area.
One person per 150 square feet of office area.
Calculations
1. For one acre of land zoned light industrial:
43,560 S.F. (0.85) (0.50) (0.50) 1/150 = 61.71 people / AC
~ 62 P/AC.
2. Tributary area population:
103 Ac Onsite
30 Ac Offsite
133 Ac Total (62 P/AC) = 8246 People
WASTEWATER DEMAND FORECAST
A. Assumptions (Source: Texas Department of Health and Texas Department
of Water Resources)
Daily Demand = 20 Gallons per day per person
Peaking Factor -- 4
Infiltration = 150 Gallons per day per acre
Calculation of peak flow plus infiltration
QT
8246 P (20 gpd/c) (4) + 133 AC (150)
659,680 + 19,950
679,630 gpd
0.68 MGD
me
WATER DEMAND FORECAST - (Onsite area only)
A.
Assump!ions
1.
Daily Demand = 24 Gallons per day per person (Source: Texas
Department of Health).
Peaking factor for conversion of average day to maximum day = 2.
Peaking factor for conversion of maximum day to maximum hour --
Calculation of maximum hour demand:
QMH = 103 AC (62 P/AC) 24 gpa/c) (2) (2)
= 613,056 gpd
= 0.61 MGD
~ --2_l-qo