Purissima Hills Water District

26375 Fremont Road

Los Altos Hills, California  94022-2699

Phone: (650) 948-1217                               Fax: (650) 948-0961

 

Service Area

 

The Purissima Hills Water District provides service to two-thirds of the Town of Los Altos Hills, a rural community adjacent to the City of Palo Alto, and unincorporated county land on the southern boundary. The District serves predominantly single-family homes on minimum one-acre lots. The largest customer is Foothill College.

 

System

 

Profile

 

Area Size

4,600 acres

Service Population

 6,140

Number of Accounts

2,184

Number of SF RWS Connections

2

Connections To SF RWS Mains

BDPL 3 and 4

Avg. Day Demand (mgd)

1.65

Avg. Day Purchases From SF RWS (mgd)

1.65

%  Demand Met With SF RWS Supplies

100.0%

Maximum Local Water Production (mgd)

0

Alternative Supply Sources

None

Interties With Other Agencies

CWS - Los Altos, City of Palo Alto

Local Storage (mg)

9.88

Days of Storage

All 4 distribution zones can meet the 8 hr criteria either separately or by pumping from zones with excess capacity

 

Summary

 

Purissima Hills Water District receives 100% of its water supply from two San Francisco/Hetch Hetchy turnouts located along the Foothill Expressway on the northern edge of the District. The SF RWS supply is gravity-fed through 18" transmission mains to the Deer Creek Pump Station and McCann Tanks at 250 feet above sea level.

 

All services within the District are gravity fed from tanks in the respective zones. The distribution system consists of 4 pressure zones, 11 tanks, 5 pumping stations, 15 pumps, and 80 miles of pipe.

 

Water Supply and Demand

 

Supply by Source

Actual
FY 11-12
(ccf)

Actual
FY 12-13
(ccf)

Actual
FY 13-14
(ccf)

Actual
FY 14-15
(ccf)

San Francisco Water

899,221

972,733

982,100

803,313

Recycled Water

0

0

0

0

Other

0

0

0

0

Total

899,221

972,733

982,100

803,313

Mgd equivalent

1.84

1.84

2.01

1.65

 

 

 

 

 

Demand by Sector

 

 

 

 

Residential

800,026

868,180

885,184

732,811

Commercial/Industrial

0

0

0

0

Other

46,231

71,493

59,871

44,713

Dedicated Irrigation

6,375

4,629

5,339

4,305

Unaccounted for

46,589

28,431

31,706

21,484

Total

899,221

972,733

982,100

803,313

Mgd equivalent

1.84

1.84

2.01

1.65

 

 

 

 

 

Per Capita Use

Actual
FY 11-12
(gpcpd)

Actual
FY 12-13
(gpcpd)

Actual
FY 13-14
(gpcpd)

Actual
FY 14-15
(gpcpd)

Residential

268

290

295

245

Gross

301

325

328

268

 

Facilities and Distribution

 

Storage Reservoirs

 

Designation

Type

Capacity
(gallons)

 

Designation

Type

Capacity
(gallons)

MC Tank 1

Steel

130,000

 

A Tank 1

Redwood

200,000

MC Tank 2

Steel

1,000,000

 

A Tank 2

Cor-ten Steel

250,000

LC Tank 1

Steel

100,000

 

N Tank 1

Cor-ten Steel

200,000

LC Tank 2

Cor-ten Steel

900,000

 

N Tank 2

Cor-ten Steel

3,000,000

HH Tank

Concrete

3,100,000

 

PM Tank

Cor-ten Steel

500,000

E Tank

Steel

500,000

 

Total

 

9,880,000

 

 

 

 

 

 

 

 

 

Interties

 

Name

No.

Diameter
(in.)

CWS - Los Altos

2

8, 12

City of Palo Alto

2

12, 12