What constitutes a body of water? It’s an important definition for some small businesses. (Jahi Chikwendiu/WASHINGTON POST)

A review of the biggest small business and startup stories from the past week, with a special focus on Washington.

Water fight: The Environmental Protection Agency recently floated new rules that would expand its regulatory oversight of U.S. waters to include small streams, river banks and floodplains. Several small employers and lawmakers warn that will subject farmers, home builders and other entrepreneurs to complicated and costly new regulations, while regulators say the rules won’t greatly expand the agency’s authority.

On track, with an asterisk: Six months shy of the new deadline, the health care law’s new online employer insurance exchange is on track for its debut in November — with one important exception. The Obama administration has finalized rules giving states another year to implement a key cost-cutting feature on the portals.

Still slow to hire: Small-business owners remain reluctant to add to their payrolls, according to several recent surveys. One reading by Wells Fargo found that 21 percent of small employers intend to hire new workers in the coming months, while a similar survey by Citibank has that number at 25 percent.

Not so slow to lend: The nation’s largest banks approved 19.4 percent of commercial loans applications from small businesses in April, up from 18.8 percent in March and the highest percentage on record, according to business lending platform Biz2Credit. Meanwhile, approvals by small banks dipped slightly.

Square circles back on small firms: Square, the increasingly popular mobile payments company, is making a foray into small-business lending. The company has started offering cash advances against future sales, approaching owners with varying offers based on credit card data Square can access.

Beckoning businesses: The Obama administration has named 12 regions of the country (most of them in the Midwest) that will receive special attention under a new program designed to help make them more attractive to manufacturing companies.

Maryland snagging start-ups: State officials had already lured promising technology firms away from Viriginia and West Virginia. Now, Maryland has poached one from the District, too, with the help of a $1 million check.

On the rise: Fundrise has grown into perhaps the country’s leading real estate crowd-funding platform and last week announced a fresh $31 million in financing from tech and real estate investors. Question is, will the company stay put in Washington?

Shopping slipped: Spending by U.S. consumers dropped 0.1 percent in April, the first time shoppers have pulled back on spending in the past year. Still, analysts aren’t worried; most expect the numbers to bounce back in May.

What are you keeping an eye on this week? Please let us know below.

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