Watermark.
Lima BOSC
Switch site 38 sites · 11 basins 8 open

Each site is one Watermark investigation. The page color says what opens; the campus line is the build on the ground — two different clocks.

MAU Maumee Basin 9 sites
2MI The Two Miamis 9 sites
SE Southeastern Basins 12 sites
NE Northeast Basins 8 sites
The page — what opens on Watermark Open · Draftfull record Queued · Watchingpreview page Restrictedrequest access
The campus — the build on the ground Investigating Confirmed Under construction Operational
All 38 sites — the network index →
Building

Groundwater & dewatering

The wells within reach of the site's pumping, and where the pumped water went.

On the record

A real impact study counts the wells within reach of the site's pumping, and it counts them before the pumping starts. This chapter reports the groundwater evidence the record supports. That evidence has three parts: the hypothetical cone, which shows what supplying the campus from the aquifer would do; the documented dewatering, where a record of one exists; and the destination of the pumped water.

The hypothetical cone

A Theis screen over the ODNR well-log census — a what-if, not a documented withdrawal, and the what-if fails: the aquifer cannot sustain the stress, which is itself the finding.

Hypothetical groundwater stress
3.92 MGD
a what-if supply well field — no groundwater withdrawal is on record
Drawdown at the well
47 ft
exceeds the saturated thickness — dewaters
Domestic wells in the radius
492
ODNR census wells [verified] inside a modeled radius

The documented dewatering

On the record: the construction-dewatering wellfield, as a superposition of Cooper-Jacob cones over the same census. Wells, rates, and dates are [verified]; every drawdown foot is [inference], bracketed by the aquifer's transmissivity uncertainty.

Dewatering wells installed
44
~4.9 MGD yield-test capacity · 2025-12-16 to 2026-05-28
Domestic wells in the composite cone
10
more than a foot of modeled drawdown

Where the pumped water went: the river record between Ottawa River at Lima OH and Ottawa River near Kalida OH reads the pumping window as not separable from natural reach gain — a screening read of cited gage records, not a measurement of the discharge itself.

The cone profile, the per-well table with the goes-dry and gradient lenses, and the full discharge screen are in the groundwater annex.

Reading this chapter · Lima · updated 2026-08-02

This chapter holds two different things, and they must not be read as one.

The first is a what-if. It asks what would happen if the campus took its 3.92 MGD of cooling makeup out of the limestone aquifer instead of the city main. The answer is that the aquifer could not supply it: the modeled cone reaches the full 47 feet of saturated thickness and dewaters. The campus does not do this. It buys treated surface water, and no groundwater withdrawal permit for it is on the record. The cone is a screen, and it is never a headline.

The second is documented, and it already happened.

The dewatering that ran through the winter

Construction dewatering pumps groundwater out of the ground so crews can work below the water table. Ohio Department of Natural Resources recordsref show 44 dewatering wells on this site, with a combined capacity of 4.9 MGD. They operated from 2025-12-16 to 2026-05-28. One well was still active at the last check.

The regional water table falls about 11.8 feet per mile toward the northwest. Wells northwest of the site are therefore down-gradient of it: groundwater moves that way. Ten mapped wells fall inside the combined cone.

Read those ten by the fraction of water column consumed, not by the drawdown in feet. The nearest is a domestic wellinput 2,056 feet away. The model puts 8.9 feet of drawdown on it, which is less than the 9.9 feet it puts on a well 42 feet farther out. But the near well has only 19 feet of column to give, so that 8.9 feet takes 47 % of it — against 18 % at the farther well, which holds 55 feet. None of the ten goes dry on these numbers.

Where the water went is not documented

Pumped groundwater has to go somewhere. Between the Ottawa River gages at Lima and at Kalida, the field’s full capacity would add up to 7.6 cfs. The honest statement of that figure is a bracket from 0 to 7.6 cfs, because the routing is not on the record. Wells were installed and sealed in stages, and no discharge record for the field has been produced.

One well roughly 3.7 miles down-gradient of the field was reportedly drilled dry and replaced. Whether that is connected to the dewatering cannot be answered from this record. Answering it needs the contractor’s dewatering discharge records and the well owner’s own log, both tracked on the leads board.

The record behind this chapter

What this chapter stands on: the records it reads, the inputs its modeled figures rest on, and the reference data behind its baselines — the same pages the record screens serve, not a second copy. A figure the record does not support stays [open] and links nothing.

Reference data