Q. Is any BCPL branch a Family Search Library?

Thanks for your question and for contacting the Baltimore County Public Library  (BCPL). 

Currently there is not a BCPL branch that is a Family Search Library. But there is one at the Bel Air branch of the Harford County Public Library. This is in Bel Air, Maryland which is about 30 minutes northeast of Towson.

Additionally, there are four Family History Centers in Maryland and two are in Baltimore.  Family History Centers (FHC's) are even better than affiliate libraries because they are essentially branches of the Family History Library in Salt Lake City, Utah.  According to the Family Search website, "Family Search affiliate libraries have privileges to limited-access Family Search databases. ... Affiliate libraries have some limitations and may not have all the services of a Family History Center. ..."

So Family History Centers are libraries, which all have computers and access to the Family Search database plus many have additional resources (microfilm, etc.) that are not available at affiliate libraries. The only other difference is the FHC's are usually staffed by volunteers and may have limited hours compared to affiliate libraries. The FHC web pages suggest you always call ahead before visiting to make sure they are open.  FYI, most FHC's will make an appointment for you (if possible) if you cannot visit during their normal open hours. 

I used the web page Find a Family History Center and FamilySearch Affiliate Libraries (https://www.familysearch.org/help/fhcenters/locations/#) and located all the Family History Centers and the one affiliate library in Maryland.  BUT I noticed that locator page also shows 2 FHC's that are not located in Maryland -- one is in the UK and the other is in Arkansas! Therefore I have included the FHC's that are in Maryland below along with their contact info and links to their individual web pages. The first one listed below, the Baltimore Maryland Family History Center, is in eastern Baltimore County between Middle River and Essex.  The second one is in downtown Baltimore City. The third one (the Columbia Family History Center) is west of Baltimore and technically in Ellicott City, MD not Columbia. But it is very near Columbia, MD so I guess that's why they named it the Columbia Family History Center. The Columbia FHC is about 30 minutes from Towson, as well.  The fourth one is in Hampstead, which is north of Baltimore and that is also about 30 minutes from Towson.  The last one in the list is the affiliate library in Bel Air which is northeast of Baltimore about 30 minutes from Towson.   

1.) Baltimore Maryland Family History Center
120 Stemmers Run Road
BALTIMORE, Maryland 21221-3403
Phone: 410-686-8481
Web: https://www.familysearch.org/wiki/en/Baltimore_Maryland_Family_History_Center
Open Hours:
Tuesday: 10:00 am-4:00 pm
Thursday: 10:00 am-4:00 pm
Saturday: 10:00 am-1:00 pm 
Holiday Schedule: 
Closed 1st weekend in April and October for General Conference. 
In July will only be open on July 15 and July 29 and in August, will only be open on Aug 12 and Aug 26.
Please, always call before coming, 410-686-8481.

2.) Baltimore Maryland Inner Harbor Family History Center
900 Madison Avenue
BALTIMORE (City), Maryland 21201-2113
Phone or Text: 443-527-7618
E-mail:  MD_BaltimoreInnerHarbor@familyhistorymail.org
Web: https://www.familysearch.org/wiki/en/Baltimore_Maryland_Inner_Harbor_Family_History_Center 
Open Hours:
Wednesday: 6:00-8:00 PM. No appointment needed, these are walk-in hours when anyone can come access resources and receive in-person assistance.
Sunday: 12:00-2:00 PM. No appointment needed.
Appointments gladly provided at other times by request. Please contact us to arrange a time outside regular hours.
SPECIAL CLOSURE NOTICE: The Center will be closed on:
Sunday, March 29, 2020 and Sunday, April 5, 2020 closed from 12-2 PM but open 2-4 PM.
If the front door is locked when you arrive, ring the white oblong doorbell near the bright green "ring doorbell" sign.
Parking:
Pay-to-park on Madison; street parking is free after 6 PM Monday - Saturday, and all day Sunday.
Free parking in the church lot, east side of the church between the church and MLK Boulevard.
No parking in the lot on the west side of the church between the church and the office building. That lot belongs to the office building and unauthorized vehicles are towed aggressively. 

3.) Columbia Maryland Family History Center
4251 Columbia Road
ELLICOTT CITY, Maryland 21042-6009
Phone: 1-410-465-1642
E-mail: MD_Columbia@familyhistorymail.org
Web: https://www.familysearch.org/wiki/en/Columbia_Maryland_Family_History_Center#Center_Contacts_and_Hours 
*Check their web page for holiday closings and/or call to make sure they will be open when you plan to visit.  
Located in the basement of the church building at 4100 St Johns Lane, Ellicott City, MD
Enter from the church's lower parking lot at 4251 Columbia Road, Ellicott City. The basement door is to the right of the staircase.
Languages: English, plus (at designated times) Spanish, Korean and Chinese. 
Open Hours: M-Th 9 am-2 pm; T-Th 7 pm-9 pm; Friday (By appointment only) 7 pm - 9 pm; Sat 9 am-12 pm. 

4.) Hampstead Maryland Family History Center
4117 Lower Beckleysville Road
HAMPSTEAD, Maryland 21074-2228
Phone: 1-410-374-1301
E-mail: MD_Hampstead@familyhistorymail.org
Open Hours: 
Monday: 10:00 am-12:00 pm
Wednesday: 9:00 am-12:00 pm and 7:00 pm-9:00 pm
Saturday: 9:00 am-12:00 pm
Holiday Schedule:
July 4th-6th, Sept 5th-7th, Oct 3rd, November 25th-30th, December 25th-31st. Closed whenever Carroll County schools are closed or delayed for bad weather.

5.) Bel Air Branch of the Harford County Public Library (affiliate library)
100 E Pennsylvania Ave
BEL AIR, Maryland 21014
Phone: 410-638-3151
Branch Hours: 
Mon - Thu 10:00 am - 8:00 pm
Fri & Sat 10:00 am - 5:00 pm
Sundays (Oct. through April) 1:00 pm - 5:00 pm
Web: https://www.hcplonline.org/belair.php

Hope this helps.