Atlanta Reservoir No. 2 (Hemphill Reservoir No. 2)

From the air

This reservoir is already full in the 1949 photo, and the 1940 photo shows the same basin. That is about 20 years older than the 1960 date in the dam inventory. Its outline never changed.

First seen

Already there in the earliest aerial, from 1940. The photos do not show it being built, so they cannot date the build.

Dam in the lidar

Lidar shows a ring embankment with a crest near 980 ft, about 4 ft above the water. On the west side it stands about 62 to 63 ft above its base. It drops to about 26 ft on the north face. The crest is even. No breach or spillway is visible.

Read from aerial photos taken between 1940 and 2026 and from USGS 3DEP lidar, then checked by a second reading. How the photos were read.

Depth

Modeled from the shoreline shape and the dam inventory’s average depth: deepest point about 66 ft. Treat it as an estimate; no survey of the lake bottom was found. How depth is estimated.

History

NID lists this basin at 83 ft high, 31.6 acres and 996 acre-ft, in Satisfactory condition and High hazard. It is off-stream storage: pumps send Chattahoochee water here, and the city says the two reservoirs together hold about 345 million gallons, enough for three to five days of supply. The Hemphill works opened in 1893 with an initial reservoir of about 200 million gallons, and a 1911 report mentions a 'new' 250-million-gallon reservoir, so this basin may date to about 1911. That link is not proven. The city's project page says only one reservoir is inactive and lists embankment repairs to both. The grounds were open to locals until 1996 fencing. 12345

Who built it

Part of the Hemphill water works planned under Mayor William A. Hemphill and built 1891-93 by contractor S. B. Mosby & Co., to designs by Robert M. Clayton and William G. Richards. The original reservoir was about 200 million gallons. When a second basin was added is not established. A November 1911 engineering report gives 178 million gallons in storage plus a new 250-million-gallon reservoir, which could fit a larger second basin built around 1908-1911 (an inference, not confirmed). 6728

Timeline

1. 1891William A. Hemphill takes office as mayor and pushes a new Chattahoochee-based water system; construction contracts for the system are awarded that year. 78
2. 1892-1893The Hemphill Avenue works are built, with an initial reservoir of about 200 million gallons on some 55 acres beside old Howell Mill Road, in a park with a summer pavilion. 68
3. 1908A taller block is added to the pumping station building beside the reservoirs. This concerns the station, not the reservoirs. 610
4. November 11, 1911Fire and Water Engineering reports 178 million gallons of storage plus a 'new reservoir' of 250 million, for 428 million total. The text does not say this is the second Hemphill basin. 2
5. Undated, 20th centuryBerkeley Park's history says locals were once allowed to fish the water works lakes and used a bandstand by the lakes for picnics and musical programs. No dates are given. Uncertain 1112
6. 1996Chain-link fences go up around the reservoirs before the Olympic Games; earlier the grounds had hosted school track meets, proms and community barbecues. 131415
7. 2018-2022City capital project WS-Hemphill Reservoir Embankment #1 includes embankment erosion and revetment repairs to both reservoirs; scheduled construction July 7 to Nov. 30, 2022; $3.22 million. 3
8. Late 2020Tunnel work linking the Hemphill treatment plant to the Bellwood Quarry raw-water reservoir (about 2.4 billion gallons) finishes under the city's Water Supply Program, adding emergency raw-water storage. 1617
9. March 2022The two-acre Hill greenspace opens beside the reservoirs, with fences moved back and views of the water and the city skyline. 181415

Names

Atlanta Reservoir No. 2 / Atlanta Reservoir (Hemphill) #2 Dam

Primary name in the National Inventory of Dams for GA01495; Georgia EPD's June 2025 inventory lists 'Atlanta Reservoir (Hemphill) #2 Dam'. 59

Atlanta City Water Works Reservoir Number One

NID alternate name for this record. USGS NHD also uses this name for the larger basin (about 32.8 acres), so numbering conflicts with the NID primary names. 519

Hemphill Reservoir No. 2

Name used in the city's water-future page, which pairs it with Reservoir No. 1 for a total of five days' supply. 4

Atlanta City Water Works Hemphill Reservoir

Wording used in Urbanize Atlanta and the Upper Westside CID for the reservoir visible from the public hill. 1815

Atlanta Water Works lakes

Neighborhood history: locals were once allowed to fish the lakes, with a bandstand used for picnics and music. 11

The dam

NID: 83 ft high, 31.6 surface acres, 996 acre-ft normal storage, local-government owner, use Water Supply, High hazard, condition Satisfactory; NID year 1960 conflicts with the 1893 origin and the stream is Unknown. Georgia EPD's June 2025 inventory lists it as Class I (state ID 060-003-00006), 83 ft, maximum storage 1,108 (units not stated), owner City of Atlanta. The city's 2018-2022 project scope covers repairs of minor embankment erosion and revetment to both reservoirs. No public contract number found. 593

Year in the inventory

1960

Dam height

83 ft

Surface

31.6 acres

Average depth

about 31.5 ft

Owner type

Local Government

Figures from the U.S. Army Corps of Engineers’ National Inventory of Dams. Its “year” is often a rebuild or survey date, and average depth is storage divided by area.

Around the lake

Water

Off-stream storage filled by pumps from the Chattahoochee raw-water intake. Water goes on to the Hemphill treatment plant, which supplies about 65 percent of Atlanta's drinking water. NID lists the stream as Unknown.

Civil War

Gen. A. P. Stewart's headquarters (Ira R. Foster house), July 16-21, 1864, stood near Howell Mill Road and Bishop Street, about 0.46 km from this point. The state marker from 1956 is reported missing.

Before 1861

Before Berkeley Park was developed from 1921, this land was part of Jesse Wood's farm, which ran to the Atlanta Water Works on the south. Howell Mill Road is the older road named in accounts of the works.

Visiting

Getting there

City-owned utility infrastructure, fenced and closed to the public. The nearby Hill greenspace at Howell Mill Road and 17th Street has been open since March 2022.

What you can see

Visitors can see reservoir water, embankments and the fence line from public streets and from The Hill. The Hemphill Avenue pumping station is part of the operating treatment plant. No spillway or interpretive marker was confirmed.

Look, don’t dig. Parks, cemeteries and preserves are off limits to digging and collecting, and private land needs the owner’s permission to enter.

Open questions

• When was this basin built, and is it the 'new' 250-million-gallon reservoir of 1911?
• Are NID's 1960 completion years for both dams a rebuild, a reclassification or an error?
• Which basin is No. 1 and which No. 2? NID primary names and the city's 180-million-gallon Reservoir #1 point one way; USGS NHD numbers them the other way.
• Combined capacity is quoted as 345 million gallons (city overview), 428 (1911) and about 510 (NID acre-feet). EPD lists 642 and 1,108 as maximum storage, with no units.
• Are there engineering drawings or inspection reports for the dam? EPD's public inventory shows Class I but not condition.
• Is this reservoir currently in service? The city's project page implies only one reservoir is inactive, but no current operations statement was found.
• Were the grounds open to all Atlantans in the segregation era? No source found.

Know something? Write to hello@historyunderfoot.org. Family papers, photos and deeds often settle these.

Where to look next

• Atlanta Water Works photographs, 1887-1924 (VIS 280) (Atlanta History Center, Kenan Research Center)
• 1949 aerial photographs of Atlanta, to see the basin outlines and pavilion grounds (Georgia State University Library / Digital Library of Georgia)
• 1911 Fire and Water Engineering passage on the new 250-million-gallon reservoir (waterworkshistory.us excerpt)
• Georgia EPD Safe Dams inventory (June 2025) for the current category; permit file 060-003-00006 (Georgia EPD Safe Dams Program)
• Atlanta Water Works annual reports and Atlanta Constitution coverage of new reservoirs c. 1908-1912 (Atlanta History Center; Georgia Historic Newspapers)
• City Council legislation for the Water Supply Program and the Hemphill embankment project (Atlanta City Council Legistar; DWM capital projects)

Sources

1. Atlanta water and wastewater system overview (CEIP-SystemOverview) City of Atlanta Dept. of Watershed Management
2. Atlanta Georgia Waterworks (quotes 'The Enlarged Filter Plant at Atlanta,' Fire and Water Engineering 50(20), Nov. 11, 1911) waterworkshistory.us
3. WS-Hemphill Reservoir Embankment #1 City of Atlanta DWM Capital Improvement Program
4. Atlanta's Solution to A Sustainable Water Future City of Atlanta DWM (h2o4atl)
5. National Inventory of Dams, record extract for GA01494 and GA01495 (project file) U.S. Army Corps of Engineers
6. Atlanta Water Works Hemphill Avenue Pumping Station Atlanta Buildings: Westside
7. Making History City of Atlanta Dept. of Watershed Management (h2o4atl)
8. WaterWorks (Atlanta's Upper West Side) Atlanta's Upper West Side (local history site)
9. Inventory of Dams (June 2025, updated June 4, 2025), Georgia Safe Dams Program Georgia EPD
10. Atlanta Waterworks Hemphill Avenue Station (NRIS 78000982), National Register listing 3/29/1978 National Park Service NPGallery
11. Our History (Berkeley Park) Berkeley Park neighborhood
12. Berkeley Park historic neighborhood document Georgia Conservancy
13. Deal struck to finally open Atlanta Waterworks park to public Urbanize Atlanta
14. Waterworks greenspace The Hill officially reopens after 26 years Rough Draft Atlanta
15. Upper Westside Improvement District Reaches Deal to Open Waterworks Hill Atlanta's Upper Westside CID
16. Water Supply Program - Atlanta, Georgia H.J. Russell & Company
17. No Worries About Water Supply Municipal Sewer and Water magazine
18. Exploring the new Atlanta Waterworks park in 19 photos Urbanize Atlanta
19. USGS NHD waterbody names (Atlanta City Water Works Reservoir Number One / Two) U.S. Geological Survey