Vector data downloaded from Natural Earth Link.
Data was imported in a PostGIS database. The river layer is dynamically generated with the following query:
SELECT
ST_AsGeoJSON(ST_Transform(geom, 4326), 5)
AS
geometry, name, scalerank
FROM
ne.ne_10m_rivers_lake_centerlines_scale_rank
WHERE
ST_Intersects(ST_Transform(geom, 4326),
(SELECT
ST_Union(ST_Transform(geom, 4326))
FROM
ne.ne_10m_admin_0_countries_lakes
WHERE
continent = 'North America'))
© OpenStreetMap contributors