Highways that transit a state with water boundaries at both entry points

[roadman65]

US 1 in GA has the St. Mary's River with FL and the Savannah River with SC.
US 1 in NJ has the Delaware River with PA and the Hudson River with NY.
US 1 in ME has the Piscataqua River with NH and the St. John River with NB Canada.

US 301 in GA has the St. Mary's River with FL and the Savannah River with SC.

US 64 in AR has the Arkansas River with OK (though not a continuous boundary, but the state line does cross where the US route crosses the river) and the Mississippi River with TN.

I-95 in GA has the St. Mary's River with FL and Savannah River with SC.
I-95 in NJ has the Delaware River now with PA and the Hudson River with NY.

I-78 in NJ has the Delaware River with PA and the Hudson River with NY.

US 46 in NJ at both terminuses is the Delaware River and Hudson River.

Any others that end at rivers or have state lines at both ends at rivers?  Could also be state designations too.

[ilpt4u]

I-64 enters Illinois from Indiana, crossing the Wabash River, and enters Illinois from Missouri, crossing the Mississippi River.
I-64 enters Indiana, crossing the aforementioned Wabash, entering from Illinois, and crosses the Ohio River, entering from Kentucky
I-64 enters Kentucky, crossing the aforementioned Ohio, entering from Indiana, and crosses the Big Sandy River, entering from West Virginia

[Great Lakes Roads]

Nebraska-Iowa-Illinois river crossings: US 20, I-80, US 30, US 6, and US 34

Example:
I-80 goes across the Missouri River in Omaha from Nebraska into Iowa & the Mississippi River in the Quad Cities from Iowa into Illinois.

[ilpt4u]

US 60/62 enters Illinois from Kentucky via crossing the Ohio and from Missouri crossing the Mississippi, just north of the confluence of the 2 rivers, and 60/62 are in Illinois for about all of a mile

[jeffandnicole]

I-295 in NJ.  And crosses the same river into 2 different states as a bonus!

[ran4sh]

I-85 and US 29 in Georgia, go from the Chattahoochee River border with AL, to the Savannah River/Lake Hartwell border with SC

I-10 and US 90 in Louisiana, go from the Sabine River (TX) to the Pearl River (MS)

US 10 in Wisconsin goes from the St Croix River (MN) to Lake Michigan (MI)

Should routes in Texas going from the Red River (OK) to the Rio Grande (Mexico) count? E.g. I-35

And DC is not a state, but I-95 and I-495 transit it with water boundaries at both entry points.

[CoreySamson]

Should routes in Texas going from the Red River (OK) to the Rio Grande (Mexico) count? E.g. I-35

In the case of I-35, no. It ends in downtown Laredo, not at the Rio Grande. US 281 doesn't count in my opinion either, because only its spur crosses the Rio Grande. Which leaves us with just US 77 for that border.

Other than US 77, I think Texas has no highways that fit the criteria (although US 59's southbound lanes miss out on crossing the Red River in Texas by mere feet, and SH-6 crosses the Red River but ends a fraction of a mile from Galveston Bay if we're going to throw in larger bodies of water as well)

[briantroutman]

Pennsylvania is a challenge since only its jagged eastern border is defined by water (and there are no bridges to Ontario over Lake Erie).

That said, I found one interesting almost example:

At the southeastern edge of the state, US 322 enters Pennsylvania from New Jersey over the Commodore Barry Bridge, of course. Approaching the western border, US 322 snakes around the south end of Pymatuning Reservoir, and just as it reaches the Ohio line, the road crosses a small run that leads into the reservoir. On this Street View, you can see the PennDOT county/municipality signs along with the "END SR"  marker right at the culvert.

So perhaps not a true water crossing and perhaps not exactly, precisely on the state line, but it's the closest example I could come up with for Pennsylvania (and a bit of a surprise at that).

[ilpt4u]

I-295 in NJ.  And crosses the same river into 2 different states as a bonus!

US 67 in Illinois does something similar, as it crosses the Mississippi twice, at its southern Illinois point from Missouri, and at its northern Illinois point from Iowa

I-275 in Kentucky, as I-275 crosses the Ohio twice, from Indiana on the west side and from Ohio on the east side

[SkyPesos]

[insert random FritzOwl interstate here]
Ferry at one end, and a ferry at the other end

[TheHighwayMan3561]

MN:
I-94 crosses the Red River at the ND border in Moorhead and the St. Croix at the WI border at Lakeland/Hudson.
US 10 crosses the Red in Moorhead and the Mississippi St. Croix right at its confluence at Prescott, WI
US 53 crosses the Rainy River in I-Falls and the St. Louis River (St. Louis Bay) in Duluth
US 2 crosses the Red in East Grand Forks and St. Louis Bay in Duluth

Two that count because there's no further for them to go:
MN 1 begins at the Red and ends on the cliffs of Lake Superior at MN 61
MN 11 begins at the Red and ends on the shores of Rainy Lake at the Sha-Sha Resort

Former:
US 61 entered on the Mississippi from Wisconsin at La Crosse and entered Canada across the Rainy River.

[Great Lakes Roads]

I-10 in Louisiana: Crosses the Sabine River from Texas and enters Mississippi by crossing the Pearl River.

[Konza]

Nebraska-Iowa-Illinois river crossings: US 20, I-80, US 30, US 6, and US 34

Example:
I-80 goes across the Missouri River in Omaha from Nebraska into Iowa & the Mississippi River in the Quad Cities from Iowa into Illinois.

Add US 18 to the list, except that it crosses the Big Sioux River from South Dakota, and crosses the Mississippi into Wisconsin.

US 136 enters Iowa by crossing the Des Moines River from Missouri.  Less than four miles later, it crosses the Mississippi into Illinois.

As Iowa is the only state whose entire eastern and western boundaries are rivers, the premise of this thread is true of any route that crosses Iowa east-west.

[jp the roadgeek]

US 1 in GA has the St. Mary's River with FL and the Savannah River with SC.
US 1 in NJ has the Delaware River with PA and the Hudson River with NY.
US 1 in ME has the Piscataqua River with NH and the St. John River with NB Canada.

US 1 can continue for NY as well.  It has the Hudson with NJ, plus it has the Byram River with CT.  CT also fits, as it has the Pawcatuck River with RI at the other end.   

Eastern US 2 for VT crosses the uppermost portion of Lake Champlain into NY, and the Connecticut River into NH.

[bulldog1979]

US 2 in Minnesota crosses into the state from North Dakota at the Red River of the North and then exits into Wisconsin at the St. Louis River. Continuing eastward, US 2 then exits into Michigan at the Montreal River, reenters Wisconsin at the Brule River and reenters Michigan at the Menominee. At one time, US 2 terminated in Sault Ste. Marie at the ferry across the St Marys River to Canada, which meant it fully transited three states, two of which twice, between water crossings.

US 8 in Wisconsin enters the state from Minnesota crossing the St. Croix River and then exits into Michigan by crossing the Menominee River.

US 10 in Wisconsin enters from Minnesota at the St. Croix River and exits on the SS Badger to Michigan.

US 61 in Wisconsin transits the state between crossings of the Mississippi River.

US 141 also transits Michigan between Menominee River crossings and transits Wisconsin between the Menominee and Brule rivers.

[1995hoo]

Probably too easy: The Trans-Canada Highway on Prince Edward Island.

[webny99]

Probably the most high-profile one for NY is I-95, which enters via the GWB and exits via the Byram River Bridge.

[dkblake]

VT: US 4 enters from NY over the Poultney River, exits to NH over the Connecticut River
NH: NH 9 starts from VT 9 over the Connecticut River, becomes ME 9 over the Salmon Falls River

[hotdogPi]

Corner clip: GA 94

[webny99]

VT: US 4 enters from NY over the Poultney River, exits to NH over the Connecticut River

Also US 2, which enters over Lake Champlain and exits over the Connecticut River.

[nexus73]

US 30 in Oregon.  On its western terminus it begins at the south end of the Astoria-Megler Bridge, which crosses the Columbia.  US 30 then crosses the Snake River co-signed with I-84.

Rick

[dkblake]

NY 440, which goes over the Outerbridge and Bayonne Bridges.

[bassoon1986]

Louisiana only has 3. Many other highways with water border crossings but they don't quite reach one state line.

I-10/US 90 already mentioned
US 84


iPhone

[1995hoo]

While the District of Columbia is not a state, the George Washington Memorial Parkway crosses water both times it enters/leaves the District when it crosses Columbia Island.

[Evan_Th]

While the District of Columbia is not a state, the George Washington Memorial Parkway crosses water both times it enters/leaves the District when it crosses Columbia Island.

So do I-95 and I-495, since they both enter and leave the District of Columbia while on the Wilson Bridge over the Potomac.