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Patapsco - Woodstock to Elkridge

Patapsco, Maryland, US


Woodstock to Elkridge

Usual Difficulty I-III (for normal flows)
Length 12.5 Miles
Avg. Gradient 14 fpm
Max Gradient 30 fpm

Eddied out in Oella

Eddied out in Oella
Photo by PJ Ottenritter taken 10/00 @ 2.3ft

Gauge Information

Name Range Difficulty Updated Level
usgs-01589000 200 - 2500 cfs I-III 01h25m 109 cfs (too low)

River Description

This long reach can be broken up into much shorter runs, and it usually is. The Hollofield Bridge to Ellicott City run, for instance, is only about 5.5 miles. See below for a description of these access points, and click on the Map tab to see them.

Time: varies wildly with water level. As little as 1.5 hrs to Ellicott City, and another 1.7 hrs to Glen Artney after very heavy rain with no play, or around 3 hours to Ellicott City and another 3 hours to Glen Artney at a mild pace under average conditions.

Difficulty: I-III at up to about 3' on the Hollofield gauge, with some areas drifting into the IV's above 4-5'+ range.

Fun Factor 6.5 out of 10. (High water can add 2 or more to this total)

Water Quality: Mostly good, with some suspicious-looking hues of brown during a heavy runoff.

History: Amazingly, this river was once a route for barrels of tobacco to get from Catonsville to the even more amazingly once-navigable tidal waters at the Route 1 bridge in Elkridge. Visit this portion some time and try to imagine a sailboat coming upstream at you. It ain't easy.

The Patapsco river is a convenient local conundrum to the paddlers of Baltimore in that it features too much whitewater for recreational boaters, and way too much flatwater for whitewater boaters. If you have the gumption in the first case, the patience in the second, or you like to experience a multitude of conditions from straight-forward rapids, to narrow chutes, to big, lake-like, half mile paddles to dangerous hazards (that are optional) thrown in for spice, then this is the place for you.

You can start with a steep carry down at Woodstock Road, (just off Rte. 99) but to avoid nearly 5 miles of mostly flatwater, put in below Daniels Dam (at the end of Daniels Rd., just off Old Frederick). To trim another couple of mostly flat miles out, begin even farther down at the Hollofield bridge, which Old Frederick Road goes over. You'll still have a good four miles down to Ellicott City, and six beyond that should you choose to continue to Elkridge. (Click on the Map tab to see the location of these access points.)

If you have difficulty getting over the sandbar just a few yards downstream, it may still be runnable for the rest of the way: this is probably the shallowest spot on the entire river. The next mile is a mostly pretty run through the deepening gorge of the state park, that features a few class 2- rapids here and there. At high water this is a nice pushy, mostly rapidless run with trees (living, not fallen) being the biggest hazards.

Just below the US 40 bridge (US 40), there is a small increase in gradient resulting in a Class II rapid which becomes a wave train at higher water levels.  This rapid is all that's left of the once deadly Union Dam.  There are still some remnents of the dam on river left and the river is still adjusting from it's removal.  The next mile or so features a variety of easy class 2 rapids, and a labyrinth of a rock gardens that will test all of your boat control skills at lower levels. For incentive to prove your narrow turning ability, pretend the rocks are mines which will explode on contact. Of course you would be a puff of smoke in the first fifty feet below 2.0 or so if this were the case. There are a few interesting ledges with very scrapy chutes, and some long pools that continue until the rocks begin turning into boulders. Soon after you can make out the old Dickey mill on river left, marking the beginning of the drops through Oella.

Make your way down on river right until you see the first decent rapid. It's a fairly long, bumpy (class 3- at lower water and 3+ or above at 3.5+') ride. Paddle down to the next rapid, a steep class 3 which ends in a nice recovery pool. There are a short combination of these coming up next called Oella Falls that culminate in Suicide, the last rapid that begins below a house sticking out of the cliff on river left, and twists left down into the backwater pool before Ellicott City. There are many lines here, and a decent surfing wave at the bottom of this at some levels. All these rapids are easy to eddy-scout at up to about 2.8 or so. Much beyond 3', and the eddies all wash out, making one wild III+/-IV run all the way from the river split (marked by a giant rock plastered with strainers in the center) to the bottom. At those levels, there are some sneaky holes with stopping potential through here, so keep a sharp eye out at the top of every big wave. A long pool takes you to the Ellicott City bridge where you can take out on river left, just before the 144 bridge.

If you decide to continue, the fun begins again. A major flood occured July 31, 2016 and changed the river considerably below the 144 bridge.  After the flood, the line below the bridge is to stay river left through the first part of the rapid moving to center, at higher water with a big, long, bouncy wave train taking you down around the left-turning bend. There are a couple of rocks to avoid under the next train bridge around the corner, but the ride mostly settles after this with class 2 rapids and some riffles.  The river begins to cut through sand/gravel bars which were deposited in the backwater of the now removed Thistle Dam.  A slightly larger rapid occurs where the Dam once was located. Shortly below here is the Illchester Road bridge which is a common take-out for this section of the river.  

The rapids below here pick up for a short bit and turn to riffles before they die for good in the backwater of the next dam, a 25-footer that's carried on river right up a steep slope, and then down around a trail to the bottom. Rumor has it that this dam has been run, maybe due to a safer design, but big rocks at the bottom, very powerful water, and well, hell, a 25-foot drop make the walk mandatory. There is a little gravel island at the bottom that makes a good place to get back in your boat at lower levels. Below here, there are some fun class 2+ rapids (turning into wild wave trains at higher levels).

The rest of this run is a pleasant drift through Patapsco State Park, featuring lots of easy riffles, some precariously shallow gravel bars at low water, and interesting scenery, including a swinging bridge, plenty of heron, and the occasional marauding beaver in colder weather. Takeout is at the Glen Artney area of the Park, marked by a brick bridge running over the water just past some ballfields and no-swimming sign on river left. If you continue on to Elkridge, you'll get to see the Viaduct, and ancient rotting train bridge (still used) that's a bit unnerving if you happen to be under it when a train comes by. The next takeout is at the Route 1 bridge on river left in Elkridge. If your shuttle happens to be a motorcycle, enjoy a beer at Daniel's, one of the last drive-up motorcycle bars on the continent. And don't ask for a draft...

StreamTeam Status: Not Verified
Last Updated: 2017-06-15 20:09:24


Rapid Summary

Mile Rapid Name Class Features (Legend)
3.0Daniels DamN/APutin
4.0Old Hollofield BridgeN/APutin Access
5.0US 40II
6.8Oella FallsII+
12.5Elkridge TakeoutN/ATakeout

Rapid Descriptions

Daniels Dam (Class N/A, Mile 3.0)

To avoid nearly 5 miles of mostly flat water, put in below Daniels Dam (at the end of Daniels Rd., just off Old Frederick).

Old Hollofield Bridge (Class N/A, Mile 4.0)

To trim another couple of mostly flat miles out, begin even further down at the Hollofield bridge, which old Frederick Road goes over. You'll still have a good four miles down to Ellicott City, and six beyond that should you choose to continue to Elkridge.

Illchester (Class N/A, Mile 9.5)

Take-out under bridge river right.

Elkridge Takeout (Class N/A, Mile 12.5)

A long pool takes you to the US 1 Elkridge bridge where you can take out on river left.

User Comments

Users can submit comments.
March 22 2017 (94 days ago)
lehs0001 (158926)
Ran this yesterday at about 180 cfs and 1.8 at the Hollofield guage. Went from below Daniels Dam to
Old Frederick Bridge. Had to scrape over quite a few spots. Still fun as first season run. At 2.0
or above should be ok. 200 cfs is a good threshold for any section below Woodstock Rd. put in. Good
area for beginners at low levels. Use a boat that has good tracking as there are decently long
stretches of flat. Lots of snags and interesting debris left over from the August 2016 Flood
January 26 2017 (149 days ago)
TonyAllred (3101)
The July 2016 flood has indeed changed the "Doughnut Bend" Rapid. Now, as you go under the MD 144
bridge at Ellicott City, take the leftmost arch. Stay to the left for the first part of the rapid,
crossing to the center right at the bottom where the cliffs are.
August 4 2016 (324 days ago)
TonyAllred (3101)
A major flood occurred in Ellicott City the evening of July 30, 2016. As of August 1, 2016 there
are 20 or so vehicles and other debris in the Patapsco River below Ellicott City. Also, according
to the Baltimore Sun, there is an ongoing 5 million gallon a day sewage spill at the flood site. I
would suggest that this stretch of the Patapsco be avoided during August 2016. Even after that,
assume that the river has changed, particularly the "Doughnut Bend" rapid immediately below
Ellicott City.
August 1 2016 (327 days ago)
TonyAllred (3101)
The 120 cfs minimum that this site uses for this run probably refers to the Cedarhurst gauge, which
was the gauge used for this run before the Hollofield gauge was re-activated. For the Hollofield
gauge, 200 -- 218 cfs would be a better minimum.
April 5 2014 (1176 days ago)
jbobarker (156271)
Strainer on the left before suicide falls is finally gone ! Yay
February 28 2014 (1212 days ago)
jbobarker (156271)
Waters cold but running about 3.5 feet in old Ellicott city. 2/28/2014
November 17 2013 (1315 days ago)
Colin AbernethyDetails
Has anyone run this section since the removal of the Union and Simkins dams? I've seen in the
comments section where people were running it during the removal, but no word on how it's changed
the river since. Also, the Bloede Dam is currently under review for removal which will make the
section from Daniels down to the inner harbor free-flowing once again.
May 5 2012 (1876 days ago)
c2buck (154395)
Ran this Friday morning, May 4, 2012 when the gauge jumped above 120cfs. Put in at Old Frederick
Rd, out at Ilchester Rd. Some good fun. Notes: Being completely new to this river, we did not know
the section flowing under Rte. 40 is closed, until well after we were committed. The bad news is
that there is some serious construction ongoing that looks no where near completion. The river is
clearly marked as 'CLOSED' with almost no reasonable method of porting your boat around the
constructiion site. The good news is that the 2 dams in this section that most of the literature
describe, have been removed making for longer, more consistent linking of rapids. Currently, there
is no logistical barrier to running the river through the construction site, and the construction
folks have done a great job of creating a fun rapid over the remains of the dam. There is, however,
obvious risk of being struck by falling construction debris and possibly legal consequences for
running a 'CLOSED' river. So when the signs come down and water is up, this will be a much improved
stretch of river for Baltimoreans with few hours and an urge to run some rapids.
April 26 2011 (2251 days ago)
jampf71 (153023)
There is currently construction on the Patapsco River. They are in the process of removing dams on
the river. We were unable to pass where Union Dam used to be. There was crane work and construction
workers not allowing us to pass. There is no easy portage there unless you want to cross route 40
or walk train tracks thru a tunnel. The good news it the old Union Dam site will eventually have a
nice rapid there instead of a nasty keeper hole.
April 10 2011 (2267 days ago)
Matt MuirDetails
Robert: if the Hollofield gauge reads the same way now as in '04, 3.56 ft = 1330 cfs.
June 5 2006 (4037 days ago)
Robert FarmerDetails
I caught this in 2004 at @ 3.56 on the Hollofield gauge--any idea what cfs this was? Anyway, it was
high, and on a similar occasion later, I paddled down to the harbor, on a cold winter day. So I'll
just say, for whitewater boaters, take out at Ellicott City. The section after that is mostly flat
water, with the 3 dam portages, the second of which had so much spray that I couldn't even see the
base of the dam. All drowning machines, for sure. Flat water paddlers should drive down below the
third dam and put in. I ran Daniels Dam on the right, but scout, because on walking trips, I saw a
log jammed at the base of the dam for a while one season. Also, Union Dam seemed like Class 5 at
high levels.
June 7 2005 (4399 days ago)
Mark CooperDetails
There is no longer a USGS Hollofield gauge. The North Branch of the Patapsco at Cedarhurst USGS
gauge http://waterdata.usgs.gov/nwis/uv?01586000 can give you an approximation (it correlates
fairly well with the old gauge). I prefer running it at higher levels (above 500 cfs). You should
be good to go at 400 cfs and above on the North Branch gauge. Another good indicator is that if
there is a wave train just past the Main Street Bridge in Ellicott City, then the Patapsco is
running. You need about an inch of rain to get the Oella section at a "fun" level. It is
very flashy, so catch it while you can and scout before you run it.

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