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Portola Valley, California

51 topographic sheets cover this place, the earliest surveyed in 1897 and the latest in 1997. It stands in the San Mateo census division. It lies in ZIP code area 94028. It stands on Bull Run Creek. The Survey maps it on the Palo Alto quadrangle. 4,456 people lived here at the 2020 count. It stands 459 feet above sea level.

Portola Valley within San Mateo County

Then and now

1897 to 1997

The same ground, surveyed 100 years apart. Drag the handle to wipe between them. Both sheets are United States Geological Survey originals; neither has been altered.

Topographic sheet of Portola Valley, surveyed 1997
Topographic sheet of Portola Valley, surveyed 1897

Compare 1897 against another survey:

On record in Portola Valley

Buildings and businesses the archive holds for this place. Each opens its own page, with the source record it came from.

On the National Register 3 records

Population over time

2 figures

Portola Valley grew from 4,353 to 4,456 between 2010 and 2020. These are the recorded population figures Wikidata holds for this place, reached through the Geographic Names Information System number this page is keyed on rather than by name, so they belong to this place and not to another of the same name. Most are census counts, but not all are: an early figure may be a founding or settlement estimate, and an estimate published within five years of a census is left out. The change column is computed, and is left blank where more than 20 years separate a figure from the one before it, because a gap that long is not a change between two counts.

YearPeople Change
20104,353
20204,456+103 (+2%)

Topographic sheets covering this place

22 surveys from 51 printed sheets

Matched by testing this settlement's coordinate against the published boundary of every sheet in the United States Geological Survey's historical collection. Each opens the scanned sheet at the Survey.

Fires near this place

139 since 1992

Regional context, not property-specific evidence. The federal wildfire occurrence database lists 139 fires within 5 miles of Portola Valley between 1992 and 2020, burning about 149 acres in total. 7 started naturally. 11 were recorded as arson. Distance is straight-line from the map coordinates, so a fire counted here may appear on a neighbouring settlement's page as well.

Reported cause Fires
Missing data/not specified/undetermined71
Equipment and vehicle use32
Arson/incendiarism11
Natural7
Misuse of fire by a minor7
Debris and open burning6
Smoking4
Power generation/transmission/distribution1

The most recent of them, most recent first, with the day each was reported and the service that recorded it.

DateCause SizeReported by Name on the report
9 September 1999Naturalunder an acreSan Mateo-Santa Cruz UnitKINGS MOUNTAIN
8 September 1999Naturalunder an acreSan Mateo-Santa Cruz UnitDRISCOLL
6 September 2013Equipment and vehicle use1.2 acresSan Mateo-Santa Cruz UnitALPINE
5 September 2020Arson/incendiarismunder an acreSan Mateo-Santa Cruz UnitCONTROL BURN
30 September 2018Missing data/not specified/undeterminedunder an acreCalifornia Department of Forestry & Fire ProtectionNB HWY 280 / SAND HILL R
3 September 2000Equipment and vehicle use2.0 acresSan Mateo-Santa Cruz UnitRAPLEY
28 September 2009Missing data/not specified/undeterminedunder an acreCalifornia Department of Forestry & Fire Protectionnot named
28 September 2005Misuse of fire by a minorunder an acreSan Mateo-Santa Cruz UnitPLAYBOWL

Settlements close enough to share some of these fires:

Every fire recorded in San Mateo County

Mines and quarries near this place

10 of 17 shown

Regional context, not property-specific evidence. The federal mineral resources record lists 17 workings within 5 miles of Portola Valley: 7 producers, 6 past producers, 4 unknowns. 7 still produce. What was taken out: Stone, Mercury, Gold, Silver. Distance is straight-line from the map coordinates, so a quarry counted here may appear on a neighbouring settlement's page as well.

Where SiteCommodity StatusRecorded
J. M. MacdonoughGold, Lead, SilverUnknown
J.M. Macdonough RanchGold, Silver, LeadPast ProducerGold
Langley Hill QuarryStone, Crushed/BrokenProducer
ChallengeMercuryPast Producer1955
Emerald LakeMercuryProducer
Farm Hill No 2MercuryPast Producer
Bahr & Ledoyen, Inc.StoneProducer
Bahr & Ledoyen, Inc.StonePast Producer
Langley Hill QuarryStoneProducer
New Page Mill QuarriesStoneProducer

Every working recorded in San Mateo County

Nearest settlements

The eight closest, with where each one stands in the county. Distances are straight-line, computed from the Geographic Names Information System coordinates.

Map PlaceDistance Sheets
Woodside Highlands0.8 miles51
Westridge1.1 miles51
Searsville (historical)1.4 miles51
Sky Londa1.5 miles37
Ladera2.2 miles51
Los Trancos Woods3.1 miles52
Stanford Weekend Acres3.3 miles51
Woodside3.3 miles37

Elsewhere

Matched on this settlement's Geographic Names Information System number rather than its name, so it cannot be a different place of the same name in another state.

Wikipedia article on Portola ValleyAn encyclopaedic summary. Its text is share-alike, so it is linked here rather than copied.
Wikidata item Q1011116The structured record the population and elevation above come from. Public domain (CC0).

Provenance

This settlement is recorded in the Geographic Names Information System as feature 1659786. The sheet list is computed by point-in-boundary test against the United States Geological Survey's historical topographic inventory. Both are works of the United States government and carry no copyright under 17 U.S.C. 105.

Wildfire. Short, Karen C. 2022. Spatial wildfire occurrence data for the United States, 1992-2020 [FPA_FOD_20221014]. 6th Edition. Fort Collins, CO: Forest Service Research Data Archive. https://doi.org/10.2737/RDS-2013-0009.6 Collected with United States Government funding and usable without additional permissions or fees.

Mines and quarries. USGS Mineral Resources Data System (MRDS) https://mrdata.usgs.gov/mrds/ A work of the United States government, no copyright under 17 U.S.C. 105.