Most of the boating here happens on water you can see across. Worden Pond covers 1,087 acres and Watchaug Pond 568, and from the ramp on either one the far shore is already in sight. The larger sheets are Watuppa Pond at 1,754 acres and Scituate Reservoir at 2,323, which is the biggest water body the pack carries. Wind gets up in the afternoon and shallow water stacks a short chop fast, and that is what shortens a day out here more often than distance does. What you want from a chart on water this size is not a course to steer. It is the shape of the bottom in a cove you have not been into before, and how much water is over the bar at the mouth of it.
The pack carries 1,262 charted water bodies. 986 of them are named, which is what lets you search a pond instead of hunting for it as a blue shape. 27 of the named lakes measure more than a square kilometer, which works out to about 247 acres, so nearly everything in here is small water. The depth on all of it is built from state elevation surveys, and the water bodies themselves come from the National Hydrography Dataset.
The count that does the work at the ramp is the second one. A name on the chart means the pond somebody described to you over the phone is a pond you can type into the search field, and that the mark you save comes back next season attached to Stafford Pond rather than to a shape you have to recognize again.
27 of the named lakes measure more than a square kilometer, about 247 acres. Everything else falls under that, much of it far under, down to mill ponds and the wide spots on small rivers. Water that size rewards a chart in a particular way. You are working out where the bottom comes up off a point, and how far into the back of a cove you can run before the lower unit finds something.
| Lake | Charted surface area |
|---|---|
| Scituate Reservoir | 9 km² (2,323 acres) |
| Watuppa Pond | 7 km² (1,754 acres) |
| South Watuppa Pond | 6 km² (1,458 acres) |
| Lake Chaubunagungamaug | 5 km² (1,260 acres) |
| Worden Pond | 4 km² (1,087 acres) |
| Copicut Reservoir | 2 km² (593 acres) |
| Flat River Reservoir | 2 km² (593 acres) |
| Watchaug Pond | 2 km² (568 acres) |
| Stafford Pond | 2 km² (494 acres) |
| Winnapaug Pond | 2 km² (469 acres) |
| Norton Reservoir | 2 km² (469 acres) |
| Green Hill Pond | 2 km² (420 acres) |
The twelve largest named lakes the Rhode Island pack carries, by charted surface area, measured from the chart polygon itself. The pack carries 1,262 charted water bodies in all, 986 of them named, and 27 named lakes larger than one square kilometer.
There is no NOAA chart for a reservoir. NOAA surveys water that commerce runs through, and that work stops at the coast. Inland depth in Helm is built from state elevation surveys instead, and the water bodies come from the National Hydrography Dataset.
The two pieces do different jobs. The hydrography gives the pack the outline and the name of each of the 1,262 water bodies in it. The elevation survey gives the water underneath a shape, so a pond arrives with contours and a depth number on it, shaded against the draft you entered once. That is the difference between a lake drawn as a blue shape with a label and a lake you can plan a route across. Draw a line from the ramp to the far bank and the shallowest point on it is marked rather than averaged away.
Scituate Reservoir, Flat River Reservoir, Copicut Reservoir and Diamond Hill Reservoir are held water. The level in any of them is a decision somebody makes. It comes down through a dry stretch and comes back after rain, and the survey that produced the contours was taken at one particular level.
So read a contour on a reservoir as the shape of the bottom rather than as a promise about clearance. The bottom has not moved. The water over it has. The line that shows where the old creek channel runs stays true at any level, and on a drawdown that channel is often the part still holding water while the flats on either side of it go thin. Because the shading responds to your draft, what the level has done to a cove shows up on the screen before it shows up under the boat.
Scituate Reservoir leads at 9.4 square kilometers, or 2,323 acres measured from the chart polygon itself. Watuppa Pond and South Watuppa Pond come next at 1,754 and 1,458 acres, two basins of what reads on the chart as one long water. Lake Chaubunagungamaug follows at 1,260 acres, and Worden Pond at 1,087 is the last of the water over a thousand acres. Below that the pack drops off quickly: Copicut Reservoir and Flat River Reservoir both come out at 593 acres, and Watchaug Pond at 568.
The packs are cut to a box rather than to a state line, so water near a border is carried by more than one of them. That is why names from the Connecticut and Massachusetts side turn up in this list, and why the neighboring packs carry some of the same water.
Further down the sizes start repeating. Winnapaug Pond and Norton Reservoir both measure 469 acres. Harold E Watson Reservoir, Lake Nippenicket and Manchaug Pond all land on 371. Beach Pond, Whitin Reservoir, Singletary Pond and Diamond Hill Reservoir sit together at 346. Acreage stops telling them apart at that point, and what separates one from the next is how the bottom is shaped, which is what the contours are for.
Inland lake depth comes from state elevation surveys rather than from nautical charts, and a reservoir sits at whatever level it is being held at that week. Treat the shape and the depth as a guide, keep a lookout, and verify locally.
Scituate Reservoir, at 9.4 square kilometers or 2,323 acres measured from the chart polygon. Watuppa Pond is next at 1,754 acres, then South Watuppa Pond at 1,458 and Lake Chaubunagungamaug at 1,260. Only 27 of the named lakes in the pack are over a square kilometer at all, so those few are the open water and the rest is pond running.
Yes. The packs are cut to a box rather than to the state line, so a pond near a border is carried by more than one pack. Beach Pond at 346 acres and Lake Chaubunagungamaug at 1,260 are both in this one. If you trailer across a line often, download the Connecticut or Massachusetts pack as well and the coverage joins up.
Depth. Watchaug Pond at 568 acres and Stafford Pond at 494 come with contours and a depth reading on the water itself, built from state elevation surveys, because no NOAA chart exists for water like that. The outlines and names come from the National Hydrography Dataset, which is where all 1,262 water bodies in the pack and the 986 names on them originate.
Helm Boating