Connecticut/Highway classification

This page outlines guidelines for the classification of highways in the State of Connecticut, drawing upon both local community consensus and national standards detailed in the United States/2021 Highway Classification Guidance. Community input was sought and discussion remains open in the OpenStreetMap slack server, particularly in the channel #local-connecticut. The comprehensive implementation of these guidelines was finalized on February 12, 2022, while continuous scrutiny of the map and the implementation of specifically curated exceptions to these guidelines persist, the latter of which are always enumerated on this page and open to reevaluation.

This initiative is rooted in the classifications of the National Highway System (NHS) and the Functional Classification system as published online by the Connecticut Department of Transportation (ConnDOT). These classifications establish a robust foundation for a standardized scheme. Nevertheless, there are instances where deviations from ConnDOT classifications are warranted, and such exceptions must be thoroughly documented and justified on this page. The majority of these exceptions primarily aim to eliminate classification spurs, a detailed explanation of which follows below.

Definitions

Motorway

highway=motorway is used for roads which satisfy the requirements set forth in the United States 2021 Highway Classification Guidance. With incidental exceptions, these roads include members of the Interstate Highway System and ConnDOT-designated members of Principal Arterial: Other Expressway. However, there are some roads belonging to the latter classification which do not bear the physical features mandated by the 2021 Highway Classification Guidance, such as the segment of CT-2A near the Mohegan–Pequot Bridge. These exceptional roads should be classified at the highest applicable level below motorway. The mentioned segment of CT-2A is thereby tagged as trunk because it belongs to the pre-2012 National Highway System. Following are the characteristics mandated by the United States 2021 Highway Classification Guidance, all of which must be satisfied for a road to be tagged as a motorway:

• Grade separation
• Limited access via on/off ramps
• No at-grade intersections or traffic signals (although on-ramps may have traffic control devices)
• Divided carriageways
• Designed and maintained to support high speeds over long distances as part of an interconnected motorway network

The tag name=* has been removed from all motorways in CT except the Wilbur Cross Parkway southwest of the I-91 interchange in Meriden and the Merritt Parkway. All other motorways in CT have no or extremely few signs on the ground bearing names. Almost all motorways in Connecticut have commemorative names designated by the state legislature. Many of those names are signed, but the signs are typically small and placed only at the origin and terminus of named segments. These names are commemorative and are not intended for navigation. Connecticut residents do not commonly refer to motorways by their legislative names. Legislative names should be tagged using official_name=*. Tagging of names that are scarcely signed in name=* on motorways that carry thousands of motorists, many of whom are navigating using OpenStreetMap data, is a disservice to many users and may be considered tagging for the renderer, especially when the appropriate tag official_name=* exists for this purpose.

Trunks

highway=trunk is used for all roads belonging to pre-2012 National Highway System routes not otherwise tagged as a motorway. Due to the volume of new roads added in 2012, only the pre-2012 routes are tagged as trunk. This includes CT-12 in Groton, the only STRAHNET Route in Connecticut.

Primary

highway=primary is used for the following roads not otherwise tagged as a higher classification (i.e., motorway or trunk):

• All members of the United States Numbered Highway System
• All NHS Routes added during or after 2012
• All NHS MAP-21 Principal Arterials
• All ConnDOT-designated Principal Arterial: Other

Secondary

highway=secondary is used for the following roads not otherwise tagged as a higher classification:

• All Connecticut State Routes
• All Connecticut Special Service Roads that do not form classification spurs when tagged as highway=secondary
• All Connecticut State Roads
• All ConnDOT-designated members of Minor Arterial
• All NHS Intermodal Connectors

Tertiary

highway=tertiary is used for the following roads not otherwise tagged as a higher classification:

• All ConnDOT-designated members of Collector, including both Major Collector and Minor Collector

Residential

highway=residential is used for named members of the local road network that are not otherwise tagged as a higher classification. This classification includes most municipal roads, as well as many private roads. Private, named roads through common areas of residential communities should also be tagged highway=residential and not highway=service. These may be closed to the general public (i.e., a "No Trespassing" sign is present and access=private is in place) but used by residents, visitors, letter carriers, delivery workers, and groundskeepers. highway=residential implies bicycle=yes and foot=yes in the United States. All roads tagged highway=residential should include name=*

Note that roads tagged highway=residential do not need to serve residential areas. The semantic distinction between highway=residential and highway=unclassified is contentious. The widespread usage of highway=residential is a consequence of the TIGER data import of 2007. Over the following seventeen years, highway=residential has become the de facto standard in many areas of the United States, including all of Connecticut. Many mappers, including contributors to this site, attempt to establish exclusive definitions and hold strong, justifiable opinions on this issue, but widespread consensus does not yet exist in the United States mapping community. At this time, tagging roads throughout the general, public road network with highway=unclassified is out of step with the status quo. General-use roads tagged as highway=residential should not be changed to highway=unclassified unless a widespread consensus is reached throughout the U.S. mapping community.

Unclassified

highway=unclassified has no established meaning in Connecticut. It has been used sparingly for narrow instances in which neither highway=residential nor highway=service is suitable. Examples include the named roads within the Pratt & Whitney campus in East Hartford and seasonal roads through Pachaug State Forest that are inconsistently accessible and not suitable for general use, as well as main roads within prisons and military installations. In those cases, the campus and the forest feature large networks of ways for which a hierarchy of roads is highly appropriate. To that end, highway=unclassified is applied to the roads which stand out as the most significant but do not satisfy the criteria of highway=residential.

Exceptions to this classification scheme

All highways in Connecticut that deviate from the classification scheme laid out in this document should be listed below. These exceptions must include a justification for breaking from the norms established in this document. The majority of these exceptions serve to eliminate classification spurs. A classification spur is a tertiary, secondary, primary, or trunk road that does not end at an intersection with a road of the same or greater classification. Generally, classification spurs are eliminated by extending the greater classification forward to the closest appropriate road. When that is not feasible, highway classification can be downgraded to bring the spur in line with the highway to which it leads. However, Connecticut State Routes should never be downgraded to a classification lower than highway=secondary. A classification spur is permissible when the only simple means to eliminate it entails downgrading part of a Connecticut State Route below highway=secondary (for example, CT-83 south of CT-2 may stand as a primary classification spur on this basis). Note that classification spurs are also permissible when they terminate at a point of intermodal transit, including major airports, train stations, and ports.

Route	From	To	Notes
Albert Street	Torrington	Torrington	[Classification spur] Mapped as tertiary rather than secondary between Litchfield Street and US-202 to resolve a secondary classification spur.
Alpha Avenue; Water Street	Stonington	Stonington	[Classification spur] A Major Collector segment comprised of Alpha Avenue and Water Street south of US-1A forms a tertiary classification spur. This is resolved by mapping that segment as residential.
Andrew Avenue	Naugatuck	Naugatuck	[Classification spur] Mapped as residential rather than tertiary between Melbourne Street and Rubber Avenue to resolve a tertiary classification spur.
Aunt Hack Road; Birch Crest Drive; Cedar Crest Drive	Danbury	Danbury	[Misc.] A one-way segment of Aunt Hack Road between Birch Crest Drive and Cedar Crest Drive has Minor Arterial classification, creating a secondary segment in one direction with no counterpart. Additionally, this segment is very narrow with sharp curves, and is clearly intended to favor traffic by local residents and not long-range or heavy traffic. A stronger alternative has been implemented by mapping Birch Crest Drive as secondary and Cedar Crest Drive as secondary between Birch Crest Drive and Aunt Hack Road, and by mapping the one-way segment of Aunt Hack Road as residential.
Bath Street; Franklin Street; Main Street; Market Street	Norwich	Norwich	[Misc.] ConnDOT classifications yield an odd secondary route between Chelsea Harbor Drive and Union Square, linking together Broadway and Courthouse Square--two one-way roads that move traffic in opposing directions. To resolve this issue and create a drivable network of secondary highways between Chelsea Harbor Drive and Union Square, the following roads have been upgraded to highway=secondary: Bath Street; Franklin Street (between Bath Street and Main Street); Main Street (between Franklin Street and Market Street); Market Street.
Beecher Road; Long Swamp Road	Bristol	Wolcott	[Classification spur] Mapped as secondary rather than tertiary to connect Willis Street (secondary classification spur) to CT-69 (primary).
Belamose Avenue	Rocky Hill	Rocky Hill	[Classification spur] Mapped as residential rather than tertiary, eliminating a tertiary classification spur.
Briar Ridge Road	Danbury	Danbury	[Classification spur] Mapped as residential rather than tertiary east of Old Ridgebury Road, eliminating two tertiary classification spurs. The road is in two segments separated by a gap, therefore creating two classification spurs.
Broad Street	New Britain	New Britain	[Classification spur] Mapped as secondary rather than tertiary between Beaver Street and Washington Street to connect Main Street (secondary) to Washington Street (secondary).
Canal Street	New Haven	New Haven	[Classification spur] Mapped as residential, rather than tertiary. This road consists of two disconnected segments, which create tertiary classification spurs.
Chamberlain Road; Clark Road; Thrall Road; Wapping Road.	East Windsor	Ellington	[Classification spur] ConnDOT classifications designate Frog Hollow Road (Ellington) as a minor collector, with that classification terminating at the East Windsor–Ellington town line, which creates a tertiary classification spur. This spur is eliminated by extending tertiary classification in the southeast direction to Wapping Road in Windsorville.
Charles Street; Seventh Street	Waterbury	Waterbury	[Classification spur] Major Collector classification extends south of the CT-8 on ramp on Charles Street onto Seventh Street, creating a tertiary classification spur. This is eliminated by downgrading this route to residential.
Coe Avenue	Meriden	Meriden	[Classification spur] Segment between Bradley Avenue and Hanover Road is mapped as tertiary rather than secondary, resolving a secondary classification spur.
College Street; Congress Avenue	New Haven	New Haven	[Misc.] A small primary outcropping south of South Frontage Road is mapped as secondary instead, resolving a strange turn that does not form a meaningful contribution to the broader network of primary highways.
Coppermine Road	Burlington	Farmington	[Classification spur] Mapped as secondary rather than tertiary to connect Stafford Road (secondary classification spur) to CT-177 (secondary).
Cross Highway	Fairfield	Westport	[Classification spur] Cross Highway is classed as minor arterial west of its intersection with the Fairfield–Westport town line, creating a secondary classification spur. There is no nearby highway of equal or greater classification to which secondary status can be extended. Instead, Cross Highway is downgraded to tertiary east of its intersection with Weston Road to eliminate the spur.
Cross Road	Waterford	Waterford	[Classification spur] Cross Road is classed as Minor Arterial north of Waterford Parkway South, creating a secondary classification spur at that intersection. This is resolved by extending secondary classification south to US-1.
CT-4	Cornwall	Torrington	[Classification spur ; Primary] Mapped as primary rather than secondary between CT-272 in Torrington and US-7 in Cornwall. This resolves a primary classification spur in Torrington by extending it to US-7, providing a primary route through what would otherwise be largest area in the state without one.
CT-8	Colebrook	Colebrook	[Primary] Mapped as primary.
CT-14	Canterbury	Windham	[Primary] Mapped as primary west of its connection with CT-14A.
CT-14A	Canterbury	Plainfield	[Primary] Mapped as primary west of its interchange with I-395.
CT-17	Middletown	Middletown	[Misc.] Saint John's Square is mapped as trunk rather than primary between Main Street (pre-2012 NHS) and CT-9 (pre-2012 NHS) to address a gap in the trunk network. Upgrading Saint John's Square provides an important linkage to promote an interconnected trunk network.
CT-32	New London	New London	[Classification spur] Pre-2012 NHS classification extends south to the intersection with Crystal Avenue, creating a classification spur when mapped as trunk. Because this NHS membership clearly serves to connect I-395 and I-95, CT-32 is mapped as primary rather than trunk south of the I-95 interchange to eliminate that trunk classification spur.
CT-32	Stafford Springs	Willimantic	[Primary] Mapped as primary. Principal north–south route in region.
CT-63	Bethany	Woodbridge	[Classification spur] Mapped as primary. This provides connectivity between two primary classification spurs: CT-63 north of Litchfield Turnpike in Bethany, and CT-63 south of CT-67 in Woodbridge.
CT-63	Watertown	Watertown	[Classification spur] Segment between US-6 and West Road is mapped as secondary rather than primary. This resolves a short primary classification spur.
CT-67	New Milford	New Milford	[Classification spur] Segment between US-202 and the Bridgewater–New Milford town line is mapped as secondary rather than primary. This resolves a lengthy primary classification spur.
CT-71	New Britain	New Britain	[Classification spur] Other Principal Arterial classification terminates at the intersection with CT-174, creating a primary classification spur. This is resolved by downgrading CT-71 to secondary between CT-174 and the CT-72 ramps on the Truman Overpass.
CT-80	Deep River	Killingworth	[Classification spur ; Primary]Mapped as primary between CT-9 and CT-79 rather than secondary. This is a significant route for long-distance travel, and mapping it as primary resolves a lengthy primary classification spur that terminates at the CT-79 rotary by extending the classification to CT-9.
CT-82	Chester	Norwich	[Primary] Mapped as primary. Principal east–west route through a large region that otherwise lacks a primary route.
CT-99	Wethersfield	Cromwell	[Primary] Mapped as primary.
CT-101	Foster, RI	Pomfret	[Primary] Mapped as primary. This is a foremost route between Providence and Hartford.
CT-117	Ledyard	Preston	[Classification spur] A short segment north of the town line and south of CT-21 is mapped as secondary to resolve a primary classification spur caused by ConnDOT classification as Other Principal Arterial.
CT-138	Jewett City	Voluntown	[Primary] Mapped as primary, despite ConnDOT classification as Minor Arterial. Primary east–west route in area. Connects with RI-138.
CT-159; Thrall Avenue; Bridge Street.	Windsor	Windsor	[Classification spur] Mapped as primary rather than secondary/tertiary. This route provides linkage between two primary classification spurs formed along CT-190.
CT-159	Windsor	Windsor	[Classification spur ; Primary] Mapped as primary rather than secondary. This major dual carriageway thoroughfare links a primary classification spur (CT-75) with the segment of CT-159 with NHS MAP-21 classification to the south of I-91.
CT-184	Groton	Groton	[Misc.] A short segment is mapped as secondary, despite ConnDOT classification as Other Principal Arterial. The section in question falls between the eastern terminus of motorway classification and the intersection with Kings Highway. This highway is tagged as highway=motorway west of this segment (due to physical criteria) and as highway=secondary east of this segment (due to State Route status and Minor Arterial classification). The result is a very short highway=primary segment in between, which serves no purpose within the greater network. This segment is downgraded to highway=secondary to eliminate this irregularity.
CT-188	Middlebury	Southbury	[Classification spur ; Primary] Mapped as primary rather than secondary between the intersection of Middlebury Road and Whittemore Road in Middlebury and the I-84 Exit 16 interchange in Southbury. This resolves a primary classification spur by extending it, providing highway=primary linkage to I-84.
CT-190	Somers	Stafford	[Primary] Mapped as primary between CT-32 and CT-83. rather than secondary. Principal east–west route in area.
CT-190	Suffield	Suffield	[Classification spur] Mapped as secondary rather than primary north of Bridge Street to resolve a primary classification spur.
CT-218	Windsor	Windsor	[Primary] Mapped as primary rather than secondary. This short segment links the portion of CT-218 with NHS MAP-21 classification to the primary highway CT-159 and the Exit 3 offramp of I-291.
CT-372	Berlin	New Britain	[Classification spur] Mapped as secondary, despite ConnDOT classification as Other Expressway and NHS classification as MAP-21. This short segment precedes the at-grade intersection at the western terminus of SR-571.
Dart Hill Road	South Windsor	Vernon	[Classification spur] Mapped as secondary rather than tertiary between Avery Street and CT-83, resolving a secondary classification spur in Avery Street by extending secondary classification to CT-83.
East Clarks Falls Road	Hopkinton, RI	North Stonington	[State line agreement] Mapped as tertiary, despite ConnDOT classifications.
Eastern Point Road; Poquonnock Road	Groton	Groton	[Misc.] John Street is a short, one-way road classified Minor Arterial. To create a complimentary secondary route in the opposite direction, Eastern Point Road is upgraded from tertiary to secondary between John Street and Poquonnock Road, and Poquonnock Road is upgraded from tertiary to secondary between Eastern Point Road and John street.
Ella T. Grasso Boulevard	New Haven	New Haven	[Classification spur] Mapped as secondary rather than primary south of the interchange with I-95 to eliminate a primary classification spur.
Elm Street; Park Street	New Haven	New Haven	[Classification spur] A short segment of Elm Street between Broadway and Park Street is tagged as tertiary rather than primary to eliminate a short primary classification spur. An adjacent, short segment of Park Street between Broadway and Elm Street is tagged as secondary (ConnDOT maps provide no classification to this segment), providing continuity between the Broadway and the rest of Park Street.
Factory Street; Mount Riga Road; Mount Washington Road	Mount Washington, MA	Salisbury	[Misc.] Mapped as unclassified or residential, rather than tertiary. This route is formed by unpaved forest roads that are unsuitable for general use associated with all other instances of highway=tertiary in the state.
Fitchville Road	Bozrah	Norwich	[Classification spur] Mapped as secondary. This short segment links CT-32 and SR-608, the latter of which ends unusually at the town line and forms a secondary classification spur.
Flower Street	Hartford	Hartford	[Classification spur] Mapped as residential rather than tertiary. This road has been split into two dead-end segments to remove the at-grade rail crossing, creating two tertiary classification spurs.
Gay Street; Thompson Street	East Haven	North Haven	[Classification spur] Mapped as tertiary, rather than secondary. These roads form a secondary classification spur leading to a tertiary road in North Haven.
Georges Hill Road	Southbury	Southbury	[Classification spur] Georges Hill Road is classified as Major Collector south of the entrance to Kettletown State Park, creating a tertiary classification spur. This is resolved by mapping Georges Hill Road as tertiary between the park entrance and I-84.
Harvard Street; White Street	Hartford	Hartford	[Misc.] The segment of White Street (Minor Arterial, highway=secondary) between Harvard Street and New Britain Avenue is closed to motor vehicles. As a substitution, the segment of Harvard Street (functional class Local) between New Britain Avenue and White Street has been mapped as highway=secondary, and the closed section of White Street is mapped as highway=residential. There exist plans to replace this intersection with a roundabout in the coming years.
Haddam Neck Road; Rock Landing Road; Injun Hollow Road	East Hampton	Haddam	[Classification spur] Portions of these three roads have the functional classification Major Collector, forming a lengthy tertiary classification spur. This has been mapped as highway=residential to eliminate the spur, as this route is a dead end and cannot be extended elsewhere. This classification may have been created in the past to lead to the now-decommissioned Connecticut Yankee Nuclear Power Plant.
Hebron Avenue	Glastonbury	Glastonbury	[Classification spur] Mapped as secondary rather than primary between the eastbound Exit 8 offramp and Main Street to resolve a primary classification spur.
Hicks Avenue	Meriden	Meriden	[Classification spur] Mapped as residential rather than tertiary to resolve a tertiary classification spur.
Kennedy Avenue	Danbury	Danbury	[Misc.] Between New Street and Main Street, there is a short dual carriageway formed by Kennedy Avenue and Elm Street. Elm Street has the functional classification Minor Arterial, which is mapped as highway=secondary, but Elm Street is oddly classified as Local. This is unusual because it creates a dual carriageway in which the two roads have different classification levels for no clear reason. To normalize this, Kennedy Avenue is mapped as highway=secondary to match Elm Street.
Lake Hayward Road	Colchester	Colchester	[Classification spur] Mapped as tertiary, rather than residential. This segment links tertiary classification spur Lake Shore Drive with State Highway 637.
Liberty Street; Patriot Drive	Danbury	Danbury	[Misc.] ConnDOT classification creates a one-way primary highway, White Street between Lee Hartell Drive and Main Street, with no primary highway in the opposite direction. To resolve this issue and create a drivable network of primary highways, a primary route was created in the opposite direction by upgrading Liberty Street and Patriot Drive (between Liberty Street and White Street) to highway=primary. Those roads have roughly equivalent AADT (annual average daily traffic) to the existing primary route, further supporting this exception.
Lighthouse Road	New Haven	New Haven	[Classification spur] This road leading to Lighthouse Point Park is classified as a Major Collector, which creates a tertiary classification spur. This spur is eliminated by mapping this road as residential.
Main Street	Bridgeport	Bridgeport	[Classification spur] The classifications of Main Street (Other Principal Arterial; MAP-21) at its interchange with CT 8/CT 25 creates a primary classification spur because it does not encompass the one-way routes leading to and from the motorway ramps. Classification has been revised to eliminate this spur by upgrading the routes through this interchange that lead to and from the motorway ramps to primary.
Main Street	Stamford	Stamford	[Classification spur] Mapped as residential rather than secondary west of Washington Boulevard, as the closure of the Main Street Bridge to motor vehicles as made this a secondary classification spur.
Main Street; West Broad Street	Stratford	Stratford	[Classification spur] Main Street (CT-113) is classed as Other Principal Arterial and MAP-21 north of its intersection with Linden Avenue, creating a primary classification spur at that intersection. It is resolved by extending primary classification to the south to the intersection with West Broad Street, and west to the interchange with I-95.
Moose Hill Road	Monroe	Shelton	[Classification spur] Mapped as tertiary, rather than secondary. The short segment of Moose Hill Road leading from Mohegan Road to the Monroe–Shelton town line is mapped as tertiary, despite classification as minor arterial, resolving a short secondary classification spur.
Mazzacolli Way	Newington	Newington	[Classification spur] Mapped as residential, rather than tertiary. This road is a short dead end, which appears to have been a thru road in the past.
Merritt Boulevard	Stratford	Trumbull	[Classification spur] Mapped as residential, rather than tertiary. This road is a dead end with the ConnDOT classification Major Collector, which creates a classification spur when mapped as tertiary.
Mountainville Road; South Street	Danbury	Danbury	[Classification spur] Mapped as tertiary, rather than secondary, to eliminate a long secondary classification spur.
New London Turnpike	Glastonbury	Glastonbury	[Classification spur] Minor arterial classification changes to major collector at the intersection with Clinton Street (ConnDOT classification Local), creating a secondary classification spur. Secondary classification is extended southward to the CT-17 ramps, eliminating that spur.
Norton Street; Old Turnpike Road	Cheshire	Cheshire	[Misc.] Two short segments are mapped as secondary due to an absence of ConnDOT classification: Norton Street between CT-322 and Whitlock Avenue and Old Turnpike Road between CT-10 and CT-322.
Old Mill Road; Old Mill Road North	Greenwich	Greenwich	[Misc.] Mapped as secondary, rather than tertiary and residential, respectively. This change extends secondary classification to all four motorway links, which otherwise stops just short of three links.
Old Turnpike Road	Beacon Falls	Beacon Falls	[Classification spur] Mapped as secondary, rather than tertiary, to eliminate a secondary classification spur caused by the northern terminus of SR-721 by extending secondary classification to CT-42.
Park Avenue; South Avenue	Bridgeport	Bridgeport	[Classification spur] Mapped as tertiary to the south of South Frontage Road and to the west of Park Avenue, respectively, resolving two secondary classification spurs.
Park Road	Putnam	Putnam	[Classification spur] Mapped as tertiary east of I-395 to remove secondary classification spur.
Pleasant Street	Hartford	Hartford	[Classification spur] Mapped as secondary, rather than tertiary. This segment connects Windsor Street (secondary) to Market Street (secondary) and US-44 (trunk). Pleasant Street was disconnected from Trumbull Street (secondary) when Dunkin Donuts Park was constructed, leaving a secondary classification spur, which is resolved by this exception.
Railroad Avenue	Bridgeport	Bridgeport	[Classification spur] Mapped as tertiary rather than residential between Fairfield Avenue Wordin Avenue. This resolves two tertiary classification spurs, Clinton Avenue and Hancock Avenue.
Scrub Oak Road	North Haven	North Haven	[Classification spur] The minor arterial classification of Pond Hill Road terminates at its intersection with Scrub Oak Road (major collector), creating a secondary classification spur. This is resolved by mapping Scrub Oak Road as secondary instead of tertiary.
Sea Hill Road	North Branford	North Branford	[Classification spur] Mapped as residential rather than tertiary. This dead end road is classified as a Major Collector, creating a tertiary classification spur. Mapping the road as residential eliminates that spur.
Shennecossett Road; Thomas Road	Groton	Groton	[Classification spur] Mapped as secondary rather than tertiary. CT-349 terminates unusually at the UConn Avery Point campus, which creates a secondary classification spur under this classification system. The spur is eliminated by extending secondary classification to Tower Avenue (SR-649).
Silver Lane	East Hartford	East Hartford	[Misc.] Mapped as primary rather than secondary between Main Street/US-5 and onramp to CT-15 southbound to connect Silver Lane (primary east of that CT-15 SB onramp due to NHS MAP-21 status) to US-5 (trunk due to NHS status).
SR-516	East Hartford	East Hartford	[Classification spur] SR-516 (Willow Street) extends slightly west its interchange with CT-2, creating a secondary classification spur. This road is mapped as residential west of the ramps to eliminate the spur.
SR-616	Bozrah	Lebanon	[Classification spur] Mapped as residential southeast of the intersection of McGrath Lane and the Norwich-Colchester Turnpike, despite its classification as a State Road. This was formerly a major route, but is now a dead end.
SR-620	Union	Union	[Classification spur] Mapped as residential despite its classification as a State Road to eliminate a secondary classification spur. This was formerly part of a major route, but was superseded by I-84.
SR-626	Hopkinton, RI	North Stonington	[Classification spur] Mapped as residential, despite its classification as a State Road. This was formerly part of a major route, but leads to Extension 184 in Hopkinton, RI, now a dead end.
SR-636	New London	New London	[Classification spur] Mapped as tertiary south of the interchange with I-95, despite its classification as a State Road. State Road classification below the I-95 links to Norwood Avenue, creating a secondary classification spur. This change resolves that spur.
SR-737	Milford	Milford	[Classification spur] SR-737 leads to the southern entrance of Silver Sands State Park, creating a secondary classification spur. This is resolved by mapping SR-737 as tertiary between Meadowside Road and Surf Avenue, and as residential from Surf Avenue to its southwestern terminus.
SR-739	Trumbull	Trumbull	[Classification spur] SR-739 extends slightly north of the CT-25 ramps, creating a secondary classification spur. This segment is mapped as residential instead of secondary to eliminate the classification spur.
SR-824	Danbury	Danbury	[Classification spur] Mapped as residential south of the interchange with I-84, despite its classification as a State Road. On current maps, State Road classification extends unusually far below the I-84 links, creating a classification spur. This change resolves that spur.
SR-827	Kent	New Milford	[Classification spur] The State Road status of SR-827 (South Kent Road) terminates at the Kent–New Milford town line, creating a secondary classification spur. This is resolved by mapping Bulls Bridge Road as secondary between SR-827 and US-7, and mapping SR-827 as residential south of Bulls Bridge Road.
SR-910	Glastonbury	Glastonbury	[Misc.] This state road is extremely short and consists of only one side of a dual carriageway, connecting the CT-2 offramp to CT-94. This unusually short route is mapped as tertiary (instead of secondary) to match the rest of Oak Street. To have such a short segment mapped as secondary is inconsistent with usage of highway=secondary in the state.
SR-914	Norwich	Norwich	[Misc.] This state road is extremely short and consists of only one side of a dual carriageway, connecting the CT-2 ramp to New London Turnpike. This unusually short route is mapped as tertiary (instead of secondary) to match the rest of Otrobando Avenue. To have such a short segment mapped as secondary is inconsistent with usage of highway=secondary in the state.
Transylvania Road; Upper Grassy Hill Road	Southbury	Woodbury	[Classification spur] Transylvania Road is mapped as tertiary, and Upper Grassy Hill Road is mapped as residential. This resolves two tertiary classification spurs and allows for functional consistency with those same roads north of the town line.
US-1	Groton	Groton	[Misc.] NHS STRAHNET classification ends at the interchange with CT-184. Trunk classification is extended southwards to the interchange with CT-349, fully linking trunk connectivity to I-95.
Wooster Street; Perry Avenue; White Street	Shelton	Shelton	[Misc.] In 1999, CT-108 was rerouted through downtown Shelton. The former alignment is still classed as Minor Arterial, creating an awkward secondary route down a narrow, residential road that is paralleled on both sides by state highways. The former alignment is mapped as residential rather than secondary to suggest to map users the lesser construction and subordinate character of the former route.
Wyllys Street	Hartford	Hartford	[Classification spur] A segment is tagged as primary rather than secondary between Charter Oak Avenue and Main Street. It links Wyllys Street north of Charter Oak Avenue (primary classification spur) and Main Street (primary).