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How TownValet works

1. Nightly download

Every night at 03:40 (US Eastern) a script downloads each city’s datasets from its open-data portal: collection zones (polygons with a pickup day), sweeping schedules, and the city’s or county’s official address points. A city whose download fails keeps its previous data; its page then shows a warning with the date of the last good copy. Each city page lists every dataset with its publisher, licence and the date the publisher last updated it.

2. Matching addresses to zones

For each published address point we test which zone polygon contains it (a point-in-polygon test; points within 25 m of a zone edge, for example on a street centre line, take the nearest zone). Where a city publishes the zone per address directly (Boston’s trash day, San Francisco’s street segment, Kansas City’s service eligibility, Chicago’s permit-parking blocks) we use that instead. The result is a street index: for each street, ranges of house numbers on the odd and even sides that share the same zones.

When you type an address, your browser downloads only the part of the index for streets starting with the same two letters, and does the match itself. Nothing you type is sent to us or to a geocoding service. If your exact number is missing from the city’s list we show the nearest number on the same street and say so.

3. Schedules and holidays

Weekly and every-other-week schedules are expanded into dates in your browser. Where a city publishes actual dates (Oklahoma City’s recycling and bulky-waste calendars, Chicago’s sweeping dates, Columbus’s rotating colour zones, which we compute from the city’s rotation), we use the dates. Holiday dates are computed from their legal definitions (for example Thanksgiving is the fourth Thursday of November). Each city’s holiday rule is taken from its official page and applied to the schedule:

• Slide: a weekday holiday moves that day and the rest of the week one day later, as the city’s page states (Washington DC, Denver except Thanksgiving week, Austin).
• Saturday make-up: the missed day is made up on Saturday (Baltimore recycling).
• Published dates: the city’s own calendar already includes the moves (Oklahoma City recycling and bulky waste, Columbus colour zones).
• Pickups may change: the city announces changes holiday by holiday and publishes no standing rule, so we move no dates and flag the holiday week (New York City, Boston, Seattle, Houston, Kansas City, New Orleans, Baltimore trash, Oklahoma City trash, Columbus weekday zones, San Francisco street cleaning, Denver’s Thanksgiving week).

4. Accuracy checks

• Computed holiday dates vs a published list (Houston)Houston lists its solid-waste holidays for this year and next. Our calculator produced 24 of the 26 published dates. Dates the city lists that the federal observance rule does not give: 2026-12-24, 2027-12-27 (for example Christmas Eve). Dates the rule gives that the city does not list: 2027-12-31. That is why, for Houston, we use the city’s own list.
• Columbus colour rotationOur rotation (business days cycling gold, gray, navy, pink, ruby, skipping observed holidays) reproduces the city’s 2026 calendar on the dates checked: 2026-01-02 gray ✓, 2026-01-05 navy ✓, and Martin Luther King Jr. Day moving the navy zone from Monday 19 to Tuesday 20 January.
• Every-other-week recycling (Houston)Week A starting 2026-01-05 gives Friday A pickups on 2026-01-09 and 2026-01-23, matching the city’s 2026 recycling calendar ✓. For Seattle, Austin, Denver and Columbus yard waste the cities do not publish which weeks are A and B in their open data, so we show “every other week (week A)” without dates rather than risk the wrong week.

Checks run with each nightly refresh; last run Monday November 2, 2026.

5. Sources and licences

Austin

• Garbage Collection Routes: City of Austin, Austin Resource Recovery — data.austintexas.gov. Licence: Public domain (City of Austin open data).
• Recycling Collection Routes: City of Austin, Austin Resource Recovery — data.austintexas.gov. Licence: Public domain (City of Austin open data).
• Yard Trimmings Collection Routes: City of Austin, Austin Resource Recovery — data.austintexas.gov. Licence: Public domain (City of Austin open data).
• Address Points: City of Austin, Austin Resource Recovery — data.austintexas.gov. Licence: Public domain (City of Austin open data).

Baltimore

• Trash and Recycling Days: City of Baltimore, Open Baltimore. Licence: Open licence under Baltimore City Code Art. 1 §9-8 (commercial use permitted).
• Address Points: City of Baltimore, Open Baltimore. Licence: Open licence under Baltimore City Code Art. 1 §9-8 (commercial use permitted).

Boston

• Trash Schedules by Address: City of Boston, Analyze Boston. Licence: Open Data Commons Public Domain Dedication and License (PDDL).
• Trash Collection Days (zones): City of Boston, Analyze Boston. Licence: Open Data Commons PDDL.
• Street Sweeping Schedules: City of Boston, Analyze Boston. Licence: Open Data Commons PDDL.

Chicago

• Street Sweeping Zones (current year): City of Chicago, Chicago Data Portal. Licence: City of Chicago Data Portal terms of use (disclaimer required).
• Residential Permit Parking zones: City of Chicago, Chicago Data Portal. Licence: City of Chicago Data Portal terms of use (disclaimer required).
• Cook County Address Points: Cook County GIS. Licence: Public domain.

This site provides applications using data that has been modified for use from its original source, www.cityofchicago.org, the official website of the City of Chicago. The City of Chicago makes no claims as to the content, accuracy, timeliness, or completeness of any of the data provided at this site. The data provided at this site is subject to change at any time. It is understood that the data provided at this site is being used at one’s own risk.

Columbus

• Refuse Collection Zones: City of Columbus, Department of Public Service / GIS. Licence: CC0 1.0 (public domain dedication).
• Recycling and Yard Waste Collection Units: City of Columbus, Department of Public Service / GIS. Licence: CC0 1.0 (public domain dedication).
• Address Points: City of Columbus, Department of Public Service / GIS. Licence: CC0 1.0 (public domain dedication).

Denver

• Solid Waste Collection: City and County of Denver. Licence: Creative Commons Attribution 3.0 (CC BY 3.0).
• Street Sweeping Schedule: City and County of Denver. Licence: Creative Commons Attribution 3.0 (CC BY 3.0).
• Addresses: City and County of Denver. Licence: Creative Commons Attribution 3.0 (CC BY 3.0).

Houston

• Solid Waste Automated Trash Pickup Areas: City of Houston, Solid Waste Management Department / Houston GIS. Licence: City of Houston Open Data terms of use (any lawful purpose, including commercial).
• Solid Waste Recycling Pickup Areas: City of Houston, Solid Waste Management Department / Houston GIS. Licence: City of Houston Open Data terms of use (any lawful purpose, including commercial).
• Solid Waste Heavy Trash Pickup Areas: City of Houston, Solid Waste Management Department / Houston GIS. Licence: City of Houston Open Data terms of use (any lawful purpose, including commercial).
• Site Addresses: City of Houston, Solid Waste Management Department / Houston GIS. Licence: City of Houston Open Data terms of use (any lawful purpose, including commercial).
• SWMD Holiday Schedule (web page): City of Houston SWMD. Licence: Facts (holiday dates) read from the city’s page.

This application uses data made available by the City of Houston through its Open Data Portal (https://data.houstontx.gov). The City of Houston makes no claims as to the content, accuracy, timeliness, or completeness of the data.

Kansas City

• Trash Day zones: City of Kansas City, Missouri (data.kcmo.org / KCMO GIS). Licence: data.kcmo.org terms of use (commercial use permitted, with notice).
• Address points: City of Kansas City, Missouri (data.kcmo.org / KCMO GIS). Licence: data.kcmo.org terms of use (commercial use permitted, with notice).

This site provides applications using data that has been modified for use from its original source, www.data.kcmo.gov, the official open data website of the City of Kansas City, Missouri. The City of Kansas City, Missouri makes no claims as to the content, accuracy, timeliness, or completeness of any of the data provided at this site. The data provided at this site is subject to change at any time. It is understood that the data provided at this site is being used at one’s own risk.

New Orleans

• Solid Waste Collection: City of New Orleans, data.nola.gov. Licence: City of New Orleans Open Data Policy (CAO Policy 135): no restrictions on use, including commercial.
• Address Points: City of New Orleans, data.nola.gov. Licence: Public domain (CC0).

New York City

• DSNY Frequencies: NYC Department of Sanitation, NYC Open Data. Licence: NYC Open Data terms of use (no restrictions on use).
• NYC Address Points: NYC Department of City Planning / DoITT, NYC Open Data. Licence: NYC Open Data terms of use (no restrictions on use).

Oklahoma City

• Trash Collection Zones: City of Oklahoma City, OKC Open Data. Licence: City of Oklahoma City Open Data Policy (no restrictions on use or reuse).
• Recycle Zones and Recycle Pickup Dates: City of Oklahoma City, OKC Open Data. Licence: City of Oklahoma City Open Data Policy (no restrictions on use or reuse).
• Bulky Waste Zones and Pickup Dates: City of Oklahoma City, OKC Open Data. Licence: City of Oklahoma City Open Data Policy (no restrictions on use or reuse).
• Addresses and Street Names: City of Oklahoma City, OKC Open Data. Licence: City of Oklahoma City Open Data Policy (no restrictions on use or reuse).

San Francisco

• Street Sweeping Schedule: City and County of San Francisco, DataSF. Licence: Open Data Commons Public Domain Dedication and License (PDDL) 1.0.
• Addresses with Units – Enterprise Addressing System: City and County of San Francisco, DataSF. Licence: Open Data Commons Public Domain Dedication and License (PDDL) 1.0.

Seattle

• Residential Garbage Routes: City of Seattle, Seattle Public Utilities / Seattle GeoData. Licence: City of Seattle open data policy (public data; no attribution required).
• Residential Recycle Routes: City of Seattle, Seattle Public Utilities / Seattle GeoData. Licence: City of Seattle open data policy (public data; no attribution required).
• Residential Food and Yard Waste Routes: City of Seattle, Seattle Public Utilities / Seattle GeoData. Licence: City of Seattle open data policy (public data; no attribution required).
• Active Addresses (MAF): City of Seattle, Seattle Public Utilities / Seattle GeoData. Licence: City of Seattle open data policy (public data; no attribution required).

Washington, DC

• Trash Pickup Days: DC GIS / Office of the Chief Technology Officer, Open Data DC. Licence: Creative Commons Attribution 4.0 (CC BY 4.0).
• Recycling Pickup Days: DC GIS / Office of the Chief Technology Officer, Open Data DC. Licence: Creative Commons Attribution 4.0 (CC BY 4.0).
• Address Points (Master Address Repository): DC GIS / Office of the Chief Technology Officer, Open Data DC. Licence: Creative Commons Attribution 4.0 (CC BY 4.0).

Software

Holiday definitions are our own code; maps are drawn from the zone polygons. No third-party scripts, fonts or images are loaded.

Cities we looked at and left out (for now)

Los Angeles (zone data last updated 2020 and published without a licence grant), Philadelphia (licence reserves all rights), Dallas (no stated licence), Phoenix, San Diego, San Antonio, Portland, Minneapolis, Miami, Providence and Nashville (no open collection-day data, unclear terms, or a schedule that has since changed). We will add them when that changes.