I missed this first big storm of the winter, 18 inches in Boston, because Logan was snowed in, and my flight from Chicago was cancelled. I didn't get back until Wednesday night, so I didn't bike to work until Thursday morning. I did try to cover all of the paths that I could, and I even got to talk with the DCR ranger who plows the Neponset Trail while I was co-leading a First Day Hike with him on New Year's Day.
Here are pictures of the paths on Thursday, December 30. Here are pictures of the Neponset Trail on New Year's Day.

Please send updates and reports on the conditions of other paths in Massachusetts to Doug Mink.

Arnold Arboretum 1.5 miles of park roads which are mostly closed to automobile traffic with no intersections Boston Parks and Harvard University	The park roads were all plowed by Thursday morning, but there was some ice along Hemlock Hill.
Blackwell Footpath A half-mile gravel path connecting the Forest Hills MBTA station and the South St. Arboretum entrance Boston Parks and Harvard University	This often gets plowed, but I haven't ridden it yet.
Washington St. Bike Lanes A mile of bike lanes on both sides of Washington St. from Forest Hills to Roslindale Square and beyond on Belgrade Ave. Boston Public Works Department	Clear except where cars were forced to park further from the curb and block them due to snow.
Arborway "Bike Lanes" 1 mile of wide paved shoulder which is unmarked but usually clear of parked cars during rush hour Department of Conservation and Recreation, Division of Urban Parks and Recreation	The shoulders are mostly clear, but they get pretty narrow sometimes. The sidewalks are plowed to bare pavement, mostly.
Jamaicaway Bikepath 1.5 miles of mostly bike/ped-separated paths paralleling a busy 4-lane parkway; two intersections with traffic lights Boston Parks Deparment	The whole path was plowed to bare pavement, but there was some snow drifted across near the boathouse.
Perkins St. Bike Lanes 1.5 miles of mostly bike/ped-separated paths paralleling a busy 4-lane parkway; two intersections with traffic lights Department of Conservation and Recreation Division of Urban Parks and Recreation	Westbound clear, eastbound snow-covered along the wall.
Olmsted Park Paths 3/4-mile of mostly bike/ped-separated paths built over Riverdale Road, across Leverett Pond from the Jamaicaway. Brookline Park Department	Plowed and clear, mostly bare pavement.
Muddy River Path 12-foot-wide 0.6 mile shared bike/ped path with no intersections Brookline Park Department and DPW	Plowed to packed powder which melted by the weekend. The contraflow cycle track wasn never plowed.
Commonwealth Ave. Bike Lanes Connecting the B.U. Bridge to Boston University Boston Transportation Department	These were totally clear near the B.U. Bridge
Brookline Bike Lanes Town of Brookline	Mostly clear.
B. U. Bridge east sidewalk Boston to Cambridge Department of Conservation and Recreation, Plowed By Mass. Highway Department or B.U.	Bare pavement by Thursday.
Harvard (Mass. Ave.) Bridge bike lanes Cambridge to Boston Department of Conservation and Recreation, Plowed By Mass. Highway Department	No report, but probably clear
Longfellow Bridge bike lanes Cambridge to Boston Department of Conservation and Recreation, Plowed By Mass. Highway Department	No report, but probably clear
Charles River Bikepaths Narrow, shared bike-ped path with few intersections Department of Conservation and Recreation, Division of Urban Parks and Recreation	From the B.U. Bridge upstream to Hawthorn St., the Cambridge side path was plowed, except near the B.U. Bridge, where it was pretty icy, and in the drifting snow area near the Weekes Footbridge.
J.F.K. Park Wide, shared bike-ped path from river to Harvard Square Department of Conservation and Recreation, Division of Urban Parks and Recreation	Clear pavement.
N. Harvard St. bike lanes Boston Boston DPW	Clear near the stadium but the southbound lanes are closed by plowed snow next to the practice fields further south.
Lincoln St. to Cambridge St. MassPike Bridge Bike/Ped connection from Harvard Square to Allston's Harvard Ave. district via Franklin St. Massachusetts Turnpike Authority	Clear to bare pavement.
Southwest Corridor Bikepath Separated Bike/Ped path with poorly-designed intersections Department of Conservation and Recreation, Division of Urban Parks and Recreation	Clear by New Year's Day.
South Bay Harbor Trail Bike/Ped path from the Federal Court House up Fort Point Channel to the Southwest Corridor City of Boston	Not checked yet, bu I suspect that the section in front of the Crosstown Development near Mass. Ave. will be done, and the path will be clear where it goes under the Expressway.
Neponset Trail Mostly paved Bike/Ped path Department of Conservation and Recreation, Division of Urban Parks and Recreation	Plowed to bare pavement, except for the "permeable" surface from Granite Ave to Shawmut Junction, which was flooded. The park planner suggested that plowing drainage channels from the trail might help I took lots of photos New Year's Day.
Somerville Community Path Wide rail trail from Davis Square to Cedar St. City of Somerville	Not checked, but probably plowed.
Red Line Linear Park Path Alewife MBTA station to Davis Square over Red Line City of Cambridge City of Somerville	Not checked but probably plowed.
Danehy Park Paths City of Cambridge	Not checked yet.
Cambridge Bike Lanes Striped lanes of varying widths on major and connecting streets City of Cambridge	The roads are clear, but the bike lanes are narrow to non-existent due to too much snow off the curb
Fresh Pond Bike Path Parallel to Fresh Pond Parkway in Kingsley Park City of Cambridge	No report yet
Alewife Parkway Bridge Sidewalk Connection from Minuteman Bikepath to Fresh Pond and beyond Department of Conservation and Recreation, Division of Urban Parks and Recreation	No report yet.
Minuteman "Commuter Bikeway" Towns of Cambridge, Arlington, Lexington, and Bedford	Details are usually posted at http://www.clearthetrail.org
Upper Charles Reservation Watertown, Newton, Waltham 4+ miles of paved and unpaved bikepaths Mass. Department of Conservation and Recreation Division of Urban Parks and Recreation	Not checked.
Stony Brook Reservation Hyde Park 4+ miles of paved bikepaths Mass. Department of Conservation and Recreation Division of Urban Parks and Recreation	These paths aren't plowed because they get relatively little transportation use and because they are used by cross-country skiers like me. There are marked narrow bike lanes on Enneking Parkway through the reservation which are probably clear.
Former Metropolitan State Hospital Belmont, Waltham paved bikepaths Mass. Department of Conservation and Recreation Division of Urban Parks and Recreation	Not checked yet.
Assabet River Rail Trail Hudson and Marlborough, so far Town of Hudson, City of Marlborough (so far)	Not checked, but probably not plowed.
Northampton Bikeway East-west across the City of Northampton City of Northampton	Craig Della Penna, who lives next to the path, reports that it is the intention of the DPW to make it passable ASAP after a storm. If the storm is significant, then they plow it repeatedly --sometimes 10-12 times during the course of the storm to ensure its usability.
Norwottuck Rail Trail Northampton to Amherst Department of Conservation and Recreation, Division of State Parks and Recreation	No report, but there wasn't much snow out west.