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

 6,150

Number of Accounts

2,201

Number of SF RWS Connections

2

Connections To SF RWS Mains

BDPL 3 and 4

Avg. Day Demand (mgd)

1.75

Avg. Day Purchases From SF RWS (mgd)

1.75

%  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 16-17
(ccf)

Actual
FY 17-18
(ccf)

Actual
FY 18-19
(ccf)

Actual
FY 19-20
(ccf)

San Francisco Water

689,261

814,270

770,703

851,999

Recycled Water

0

0

0

0

Other

0

0

0

0

Total

689,261

814,270

770,703

851,999

Mgd equivalent

1.41

1.67

1.58

1.75

 

 

 

 

 

Demand by Sector

 

 

 

 

Residential

627,686

715,387

672,238

746,898

Commercial/Industrial

0

0

0

0

Other

37,137

43,425

54,239

42,089

Dedicated Irrigation

0

4,888

4,508

4,814

Non-Revenue Water

24,438

50,570

39,718

58,198

Total

689,261

814,270

770,703

851,999

Mgd equivalent

1.41

1.67

1.58

1.75

 

 

 

 

 

Per Capita Use

Actual
FY 16-17
(gpcpd)

Actual
FY 17-18
(gpcpd)

Actual
FY 18-19
(gpcpd)

Actual
FY 19-20
(gpcpd)

Residential

209

283

224

249

Gross

230

271

240

284

 

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